DEPT OF CHEMISTRY
| Researcher : Albano DRB |
| List of Research Outputs |
| Sun H. , Albano D.R.B. and Fung Y.S. , Piezoelectric Quartz Crystal Biosensor for Detection of Protein Biomarker for Infective Disease, Conference proceeding of Biosensors 2010, 20th An niversary World Congress on Biosensors, Glasgow, United Kingdom, May 28 to May 30, 2010 . P.1.10. |
| Researcher : An H |
| List of Research Outputs |
| Ma C. , Kwok W.M., An H. , Guan X. , Fu Y. , Toy P.H. and Phillips D.L. , A Time-Resolved Spectroscopic Study of the Bichromophoric Phototrigger 3', 5'-Dimethoxybenzoin Diethyl Phosphate: Interaction Between the Two Chromophores Determines the Reaction Pathway, Chemistry - A European Journal . 2010, 16: 5102-5118. |
| Ma C. , Kwok W.M., An H. , Du Y. , Toy P.H. and Phillips D.L. , Femtosecond Transient Absorption and Nanosecond Time-reso lved Resonance Raman Study of Photo-deprotection Reactions of Benzoin Caged Phototriggers , Femtochemistry IX: Femtochemistry, Femtobiology, and Femtophysics -- Frontries in Ultrafast Science and Technology, Beijing, China, August 8-13, 2009 . P-43: 111. |
| Ma C. , Kwok W.M., An H. , Fu Y. , Toy P.H. and Phillips D.L. , Time-resolved Spectroscopy Studies of the Bichromophoric Phototrigger 3', 5'-dimethoxybenzoin Diethyl Phospate, The 2nd Asian Spectroscopy Conference, Seoul, Korea, November 30 - December 3, 2009 (Poster Presentation) . 2009. |
| Researcher : An X |
| List of Research Outputs |
| An X. , Ng S.M. , Xie D., Zeng Y.X., Sze J. , Wang J. , Chen Y.C., Chow B.K.C. , Lu G., Poon W.S., Kung H.F., Wong B.C.Y. and Lin M.C. , Functional characterisation of cell cycle-related kinase (CCRK) in colorectal cancer carcinogenesis. , European Journal of Cancer . 2010, 46: 1752-1761. |
| Researcher : An XM |
| List of Research Outputs |
| Yu F. , Ng S.M. , Lum C.T. , Cheung K.C. , An X.M. and Lin M.C. , Functional Characterization of Interferon Induced Transmembrane Protein 1 (IFITM1) in Colorectal Carcinogenesis, 34th FEBS Congress: Life's Molecular Interactions; Prague, Czech Republic, 4-9, July, 2009. (P4-140, Publishe d in the FEBS Journal) . 2009, 276 (s1): 134. |
| Researcher : Au KM |
| List of Research Outputs |
| Au K.M. , Wong M.C. , Chen Z. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , A Novel Class of Bis-cyclometalated Alkynylgold(III) Complexes – Synthesis, Characterization, Photophysics, Electrochemistry and the First Observation of Electrogenerated Chemiluminescence, The 5th International Conference on Gold Science, Technology and its Applications (organized by World Gold Council), Heidelberg, Germany, July 26–29, 2009 . |
| Au K.M. , Wong M.C. , Zhu N. and Yam V.W.W. , Luminescent Cyclometalated N-Heterocyclic Carbene-Co ntaining Organogold(III) Complexes: Synthesis, Characterization, Electrochemistry, and Photophysical Studies, Journal of the American Chemical Society . 2009, 131: 9076-9085. |
| Au K.M. , Chen Z. , Wong M.C. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , Synthesis, Characterization, Photophysical Studies, Electrochemistry and Electrogenerated Chemiluminescence of Bis-cyclometalated Alkynylgold(III) Complexes and their Applications in Organic Light-Emitting Devices, The 42 nd International Union of Pure and Applied Chemistry (IUPAC) Congress, Glasgow, United Kingdom, August 2-7, 2009 . P701_030. |
| Au K.M. , Chen Z. , Wong M.C. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , Synthesis, Characterization, Photophysical Studies, Electrochemistry and the First Observation of Electrogenerated Chemiluminescence of Bis-cyclometalated Alkynylgold(III ) Complexes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P217. |
| Researcher : Brown GD |
| Project Title: | Gradient diffusion-attenuated NMR spectroscopy for the analysis of multi-component mixtures |
| Investigator(s): | Brown GD |
| Department: | Chemistry |
| Source(s) of Funding: | Other Funding Scheme |
| Start Date: | 12/1994 |
| Abstract: |
| Spectroscopic analysis of multi-component mixtures has always required a physical separation of the components by some chromatographic technique prior to the acquisition of a characteristic spectrum from each component. In recent years there has been a poliferation of "hyphenated" techniques based on this very principle. The modern capability to generate magnetic-field gradients in NMR Spectroscopy opens up the possibility of differenti ating compounds by their diffusion characteristics. The project aims to investigate whether this molecular property can be applied to resolve different components when present simultaneously in the same mixture. If successful, NMR analysis of complex mixtures would then be as simple a matter as NMR analysis of ind ividual compounds, and the need for prior chromatography will have been removed, resulting in greater simplicity and wider applicability of NMR in the analysis of mul ti-component mixtures. |
| Researcher : But YS |
| List of Research Outputs |
| But Y.S. , Lu J. and Toy P.H. , Organocatalytic Mitsunobu Reactions Using 3,5-Dinitrobenzoic Acid, Synlett . 2010, 21: 1115-1117. |
| Researcher : Chan AYL |
| List of Research Outputs |
| Cheung M.C.H. , Chau K.H.B. , Chan A.Y.L. , Ng K.T. , Wu M.H. and Briscoe J.A.M.E.S., Regulation of Sox9 Function by SUMOylation in avian neural crest development, In: Shinichi Aizawa Maria Leptin Nancy Papalopulu Claudio D Stern Dider Stainer Patrick Tam, Mechanisms of Development 16th International Society of Developmental Biologists Congress 2009 Book of Abstracts . Elsevier, 2009, 126: S308. |
| Researcher : Chan CK |
| List of Research Outputs |
| Li X. , Lam H.Y. , Zhang Y. and Chan C.K. , Salicylaldehyde Ester-Induced Chemoselective Peptide Ligations: Enabling Generation of Natural Peptidic Linkages at the Serine/Threonine Sites, Organic Letters . 2010, 12: 1724-1727. |
| Researcher : Chan DSB |
| Project Title: | Structural determination of Rho GTP-activating protein (RhoGAP) in Deleted in Human Liver Cancer 1 (DLC1) |
| Investigator(s): | Chan DSB, Sun H |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 08/2008 |
| Completion Date: | 07/2009 |
| Abstract: |
| Deleted in human liver cancer 1 (DLC1) is a cance r related gene. It was found by PCR-based subtractive hybridization using DNA extracted from normal liver and hepatocellular carcinoma (HCC) tissue. The gene was found homologous to rat RhoGAP cDNA and located at chromosome 8p21.3-22 (1). Deletion and loss of heterozygosity frequently happen at chromosome 1p, 4q, 8p, 13q, 16q and 17p in hepatocellular carcinoma (HCC) (2-6). Full length DLC1 encodes a multidomain protein with 1091 amino acid residues (1). It consists of an N-terminal sterile α-motif (SAM), a middle Rho GTP-activating protein (RhoGAP) and a carboxyl steroidogenic acute regulatory-related lipid transfer (START) domain (3,7) (Fig.1). The RhoGAP is a negative regulator of small GTP-binding proteins (G proteins) in Rho (Ras homology protein) family (8,9). The intrinsic GTP hydrolysis activity of Rho is very slow. However, the activity is dramatically enhanced by orders of magnitudes with the binding of GAP (9-11). Therefore, Rho can be able to switch between biologically active GTP bound and inactive GDP bound form. Rho controls various cellul ar signaling pathways, such as actin cytoskeletal reorganization, actin stress fibers formation, cell proliferation, gene transcription and cell cycle progression (12-15). Among 21 subfamily members in Rho family, RhoA, Cdc42 and Rac1 have been well studied (16). In in vitro GAP assay, DLC1 RhoGAP specifically hydrolysed GTP in Rh oA-GTP and Cdc42-GTP (3). Clinical studies demonstrated that low level or even lack of DLC1 mRNA expression in HCC patient cells was due to allelic loss of locus and methylation of CpG island (3,17). The loss of RhoGAP in HCC cells thus abolishes the regulation between the active and inactive form of RhoA and Cdc42 under the Ras signaling pathway. The uncontrollable activation of Rho proteins leads to oncogenic transformation, tumor cell invasion, change in cytoskeletion organiza tion, cell adhesion alteration, disruption of cell-to-cell junctions and metastasis (18-21). However, the structural and functional role of RhoGAP still remains unclear. In the proposed project, three main objectives were proposed: 1. Preparation of human DLC1-RhoGAP domain for structural study We will produce 15N and 15N/13C labeled DLC1-RhoGAP sample. Intact protein or tag-fu sion protein with (Histidine)6 or GST will by produced by E.coli. The expression, removal of tag-fusion, purification and buffer conditions will be optimized to give high quality (more than 95% in purity) and quantity (above 1 mM) for NMR experiments. 2. Determination of structure of DLC1-RhoGAP domain in solution We will determine the three dimensional protein structures by multidimensional, heteronuclear NMR. The backbone dynamic will be characterized by 15N relaxation experiments. 3. Illustration of the differences or similarities of DLC1-RhoGAP domain with other known crystal/NMR structures of RhoGAPs We will compare our DLC1-RhoGAP domain three dimensional structure arrangement with the existing RhoGAPs, especially RhoAGAP and Cdc42GAP domain structures using computer program, such as DaliLite, to figure out any special structural criteria for substrate specificity. The success of the proposed study greatly depends on obtaining milli-gram quantities of soluble, properly folded, mono-dispersed RhoGAP protein. Since there are 3 cysteines (Cys 669, Cys 698 and Cys 791) present in the protein, we will pay particular attention to the possible formatio n of functional disulfide bond. It is well-known that protein requires functional disulfide bond which expresses in E.coli may yield insoluble material in inclusion bodies. In order to circumvent such a problem, we will express the protein in periplasmic space by the pelB signal sequence of pET-22b(+) vector. If the formation of inclusion persists, various protein refolding condit ions will be used, such as, (1) the gradual removal of GnHCl by dialysis, (2) gradual dilution and (3) fast dilution of GnHCl follow by dialysis. Various reagents such as glycerol, arginine and PEG will be also tried to aid in these efforts. Redox system will be set up as well for disulfide bond formation by dialysis into buffer containing 5 mM reduced GSH and 1 mM GSSG. |
| List of Research Outputs |
| Du X. , Wang X. , Chan D.S.B. and Sun H. , Expression, purification and characterization of the N-terminal domain of the human copper transporter (hCtr1), 14th International Conference on Biological Inorganic Chemistry, Nagoya, Japan, July 25-30 (published in J. Biol. Inorg. Chem. 2009, 14, Suppl1, P534) . 2009, 14. |
| Wang X. , Du X. , Li H. , Chan D.S.B. and Sun H. , Effect of the N-terminal of the human high affinity copper transporter 1 (hCtr1) on cisplatin hydrolysis and uptake, 14th International Conference on Biological Inorganic Chemistry, Nagoya, Japan, July 25-30 (published in J. Biol. Inorg. Chem. 2009, 14, Suppl 1, P305) . 2009. |
| Researcher : Chan DSH |
| List of Research Outputs |
| Chan D.S.H. , Lee H.M. , Che C.M. , Leung C.H. and Ma D.L. , A Selective Oligonoucleotide-Based Luminescent Switch-On Probe for the Detection of Nanomolar Mercury(II) ion in Aqueous Solution., Chemical Communications . 2009, 48: 7479-7481. |
| Chan D.S.H. , Lee H.M. , Yang F. , Che C.M. , Wong C.C., Abagyan R., Leung C.H. and Ma D.L. , Structure-Based Discovery of Natural-Product-like TNF-alpha Inhibitors, Angewandte Chemie International Edition . 2010, 49: 2860-2864. |
| Chan D.S.H. , Lee H.M. , Yang F. , Che C.M. , Wong C.C.L., Abagyan R., Leung C.H. and Ma D.L. , Structure-Based Discovery of Natural-Product-like TNF- a Inhibitors, Angewandte Chemie International Edition . 2010, 49: 2860-2864. |
| Lee H.M. , Chan D.S.H. , Yang F. , Lam H.Y., Yan S.C., Che C.M. , Ma D.L. and Leung C.H. , Identification of natural product Fonsecin B as a stabilizing ligand of c-myc G-quadruplex DNA by high-throughput virtual screening, Chemical Communications . 2010, 46: 4680-4682. |
| Researcher : Chan GKY |
| Project Title: | Fuel cell research towards a clean environment |
| Investigator(s): | Chan GKY, Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | The University of Hong Kong Foundation Seed Grant |
| Start Date: | 03/2001 |
| Abstract: |
| To accelerate and broaden existing fuel cell research, to foser external links and collaborations. |
| Project Title: | Electrochemical Co-generation of Green Oxidants |
| Investigator(s): | Chan GKY |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2008 |
| Abstract: |
| Achieve simultaneous generation of hydrogen peroxide and ozone in a single electrochemical cell by appropriate selections of electrode materials, electrolyte enviro nments, ion selective membranes, voltage and current parameters for cathode and anode. Optimization of cathodic generation of hydrogen peroxide in acid media. Optimization of anodic generation of ozone for low acidity 1 < pH < 7. Optimization of hydroxyl radical generation via conditions and ratio of hydrogen and ozone generated . |
| Project Title: | Metal/metal oxide/carbon multi-scale functional composites derived from mesoporous titania |
| Investigator(s): | Chan GKY, Ngan AHW |
| Department: | Chemistry |
| Source(s) of Funding: | NSFC/RGC Joint Research Scheme |
| Start Date: | 04/2008 |
| Abstract: |
| To synthesize mesoporous titania/carbon and other derived nanocomposites with structures tunable in mult iple length scales possessing high surface area, porosity, and connectivity; to synthesize nanocomposites with metal and metal oxides to achieve desirable functional properties; to investigate the performance of these novel materials in photocatalytic, catalytic, electrochemical, and mechanical applications; characterization of titania/carbon/metal composites. |
| Project Title: | Dehydrogenation of Formic Acid Catalyzed by Supported Mixed Metal Nanoparticles |
| Investigator(s): | Chan GKY |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2009 |
| Abstract: |
| 1) to investigate the optimum composition of mixed metal nanoparticles for hydrogen generation from formic acid at low temperature. 2) to investigate the optimum catalyst support for the dehydrogenation reaction. 3) to investigate the kinetics and selectivity. |
| Project Title: | Synthesis of metal nitride materials for pseudocapacitors |
| Investigator(s): | Chan GKY |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 03/2009 |
| Completion Date: | 02/2010 |
| Abstract: |
| To investigate synthetic routes to produce nanocrystalline vanadium nitride and study the electrochemical capacitance properties as potential pseudocapacitor materials. Extension of the synthetic routes will be made to fabricate other multi-valent transition metal nitride s to see of these materials also show promise as pseudocapacitors materials. Introduction of mesostructures using templating techniques can increase surface area for better perfor mance. The high cost of ruthenium-based materials which are used for supercapacitors, is driving researchers to investigate the potential of other metal-oxides or even non-oxid es, e.g. metal-nitrides as alternative materials for pseudocapacitors. The results of a recent publication has indicated that transition metal nitrides may potentially form a new class of supercapacitor materials whose performanc e may even exceed that of the well-known ruthenium oxides. Thus, it is of interest to further investigate synthetic routes to producing these materials, to characterize their electrochemical capacitance properties, and obtain more information about the mechanisms that may be op erating to induce charge storage in these materials so that further improvements on their performance can be made. |
| Project Title: | Multi-scale Structuring of Porous Electrodes for Supercapacitors and Fuel Cells. |
| Investigator(s): | Chan GKY, Leung MKH |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 11/2009 |
| Abstract: |
| 1) Develop a synthetic protocol to create electrodes with porous structure controlled in several length scales. 2) Study the performance of multi-scale porous electrodes in relation to applications of capacitors. 3) Study the performance of multi-scale porous elect rodes in relation to applications of fuel cells. 4) Correlate performance to structural parameters to arrive at a strategy for developing optimum electrode for applications. |
| Project Title: | Multi-scale structured electrode materials for clean energy applications |
| Investigator(s): | Chan GKY |
| Department: | Chemistry |
| Source(s) of Funding: | Croucher Senior Research Fellowships in Natural Sciences, Technology and Medicine |
| Start Date: | 05/2010 |
| Abstract: |
| Refer to hard copy |
| List of Research Outputs |
| Bai Y., Li W. , Liu C., Yang Z.H., Feng X., Lu X.H. and Chan G.K.Y. , Stability of Pt Nanoparticles and Enhanced Photocatalytic Performance In Mesoporous Pt-(anatase/TiO 2 (B)) Nanoarchitecture, Journal of Materials Chemistry . 2009, 19: 7055-7061. |
| Chan G.K.Y. , Consultant, Zentric Inc. (period from 1/9/2009 to 31/8/2010) . 2009. |
| Chan G.K.Y. , Croucher Foundation Senior Fellowship, 2010. |
| Chan G.K.Y. , Electrochemical Co-Generation of Ozone and Hydrogen Peroxide in Water, Invited Talk (morning session) in Xian JiaoTong University, Xian, China, October 26, 2009 . 2009. |
| Chan G.K.Y. , Electrochemical Means of Energy Savings and Emissions Reduction, Xiangshan Science Conferences the 363rd Session: Emission Reduction in the Process Industry, Beijing, China, December 8-10, 2009 . 2009. |
| Chan G.K.Y. and Cheng S. , High Voltage Dual Electrolyte Power Sources, Licensing agreement on 14/12/2009 for the invention . 2009. |
| Chan G.K.Y. and Cheng S. , High-Voltage Dual Electrolyte Electrochemical Power Sources, The 216th Electrochemical Society Meeting, Vienna, Austria, October 4-9, 2009 . |
| Chan G.K.Y. , Ions in Pores: Energizing the World under Constraints, Beijing University of Chemical Technology, College of Chemical Engineering, Beijing, China, May 24, 2010 . 2010. |
| Chan G.K.Y. , Li F. , Ting S.W. and Lam Y.L. , Mesoporous Carbons as Electrode Materials for Capacitors and Fuel Cells, 4th Asian Conference on Electrochemical Power Sources, Taipei, Taiwan, October 9-11, 2009 . |
| Chan G.K.Y. , Mesoporous Carbons for Electrocapacitors and Fuel Cells, Adam Mickiewicz University, Poznan, Poland, October 12, 2009 . 2009. |
| Chan G.K.Y. , Multi-scale Structured Composite Materials for Electrochemical Power Sources, Zhejiang University, State Key Laboratory for Clean Energy Utilization, Hangzhou, China, May 14, 2010 . 2010. |
| Chan G.K.Y. , van der Laak N.K. , Li F. , Lam Y.L. , Ting S.W. and Yang C. , Multi-scale Structuring of Composite Electrode Materials for Fuel Cells and Energy Applications, 2nd IWNA International Workshop on Nanotechnology and Application, Vung Tau, Vietnam, November 12-14, 2009 . 2009. |
| Chan G.K.Y. , Multi-scale Structuring of Composite Electrode Materials for Fuel Cells and Energy Applications, Invited talk (afternoon session) in Xian JiaoTong University, Xian, China, October 26, 2009 . 2009. |
| Cheng S. and Chan G.K.Y. , High-Voltage Dual Electrolyte Electrochemical Power Sources, ECS Transactions . 2010, 25: 213-219. |
| Li F. , van der Laak N.K. , Ting S.W. and Chan G.K.Y. , Varying Carbon Structures Templated From Kit-6 for Optimum Electrochemical Capacitance , Electrochimica Acta . 2010, 55: 2817-2823. |
| Li W. , Bai Y., Liu C., Yang Z.H., Feng X., Lu X.H., van der Laak N.K. and Chan G.K.Y. , Highly Thermal Stable and Highly Crystalline Anatase TiO 2 for Photocatalysis, Environmental Science Technology . 2009, 43: 5423-5428. |
| Ting S.W. , Cheng S. , Tsang K.Y. , van der Laak N.K. and Chan G.K.Y. , Low Activation Energy Dehydrogenation of Aqueous Formic acid on Platinum–ruthenium–bismuth Oxide at Near Ambient Temperature and Pressurew, Chemical Communications . 2009, 47: 7333-7335. |
| Zhang Q. , Chan G.K.Y. and Quirke N., Molecular Dynamics Simulation of Water Confined in a Nanopore of Amorphous Silica, Molecular Simulation . 2009, 35: 1215-1223. |
| Researcher : Chan HY |
| List of Research Outputs |
| Chan H.Y. , Lam J.W.Y., Wong M.C. , Tang B.Z. and Yam V.W.W. , Chiral Poly(4-ethynylbenzoyl-L-valine) Induced Helical Self-assembly of Platinum(II) Terpyridyl Complexes with Tunable UV-vis Absorption, Emission and Circular Dichroism Changes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P214. |
| Yam V.W.W. , Hu Y. , Chan H.Y. and Chung Y.S.C. , Reversible pH- and Solvent-Responsive Micelle-Mediated Self-Assembly of Platinum(II) Terpyridyl-Based Metallo-Sup ramolecular Diblock Copolymers, Chemical Communications . 2009, 6216-6218. |
| Researcher : Chan KM |
| List of Research Outputs |
| Chan K.M. , Gadolinium(III) Tetraazamacrocyclic Complexes for Magnetic Resonance Imaging Contrast Agents (PhD Thesis) . 2009. |
| Researcher : Chan KMC |
| List of Research Outputs |
| Chan K.M.C. , Design and Synthesis of Luminescent Branched Multinuclear Platinum(II) Alkynyl Complexes and the Study of their Two-Photon Absorption Properties (PhD Thesis) . 2010. |
| Chan K.M.C. , Tao C.H. , Tam H.L., Zhu N. , Yam V.W.W. and Cheah K.W., Synthesis, Characterization, Luminescence and Non-linear Optical (NLO) Properties of Oxadiazole- and Truxene-Containing Platinum(II) Alkynyl Complexes with Donor-Acceptor Functionalities, The 42 nd International Union of Pure and Applied Chemistry (IUPAC) Congress, Glasgow, UK, August 2-7, 2009 . P701_46. |
| Chan K.M.C. , Tao C.H. , Tam H.L., Zhu N. , Yam V.W.W. and Cheah K.W., Synthesis, Characterization, Luminescence and Non-linear Optical Properties of Oxadiazole- and Truxene-containing Platinum(II) Alkynyl Complexes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P213. |
| Researcher : Chan LF |
| List of Research Outputs |
| Low K.H. , Li C.H., Roy V.A.L., Chui S.Y. , Chan L.F. and Che C.M. , Homoleptic copper(I) phenylselenolate polymer as a single-source precursor for Cu2Se nanocrystals. Structure, photoluminescence and application in field-effect tra nsistor, In: David MacMillan , Chemical Science . The Royal Society of Chemistry, 2010, 1: 515-518. |
| Researcher : Chan MY |
| Project Title: | Investigation of the origin of open-circuit voltage in small-molecular based organic photovoltaic devices |
| Investigator(s): | Chan MY |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 05/2008 |
| Completion Date: | 04/2010 |
| Abstract: |
| Photovoltaics (PV) comprise the technology to convert sunlight directly into electricity. The term “photo” means light and “voltaic” means electricity. A PV cell, also known as “solar cell”, is primarily constructed of inorganic semiconductor that generates electricity when sunlight falls on it. Nowadays, most of PV cells are silicon-based, in which their power conversion efficiencies (i.e. efficiency to convert incident solar power to useful electric power) achieve up to 24%. Because of their safe, environmentally friendly, and unlimited availability benefits, PV cells have found applications in customer electronics, likes watches and calculators, small scale remote residential power systems, as well as highway signs in USA and Canada. The standard silicon-based PV technology reaches its mature stage; however, it is still difficult and very expensive to produce efficient silicon-based PV devices, especially for large surface area, due to problems in producing large Si crystals without significant efficiency-degrading defects. Currently, solar generati ng power is four to six times more expensive to customers than coal generating power. There is a prevailing need for the development of new materials and concepts for photovoltaic energy conversion that could potentially reduce the manufacturing cost of PV cells. Development of research in the field of OPV devices has been env isaged as a possible route. OPV cells provide many foreseeable advantages, such as simple fabrication process, light weight, flexibility, and solution-processibility for large area production. In the past couple of decades, many smart device configurations and high-performance materials have been used to improve the photovoltaic performance. Encouraging progress with power convers ion efficiencies up to 6% has been recently reported. More recently, an industry analyst firm NanoMarkets forecasts the global market for thin film and organic photovoltaic modules worth over US$ 2.3 billion in the year 2011. OPV cell generally consists of photoactive organic materials (so called “donor-acceptor” system) sandwiched between two conducting electrodes. Under light illumination, excitons are generated in the photoactive layers and some would dissociate into electrons and holes at the donor/acceptor heterointerfaces. These charge carriers are subsequently collected at the respective electrod es, contributing to the photocurrent, provided that the offset energies at the donor/acceptor interfaces are sufficiently large for efficient change dissociation. The power conversion efficiency of OPV cells depends on the optimization of the short-circuit current density (JSC), the open-circuit voltage (VOC), and the fill factor (FF). Various approaches have been attempted to improve the JSC and FF; while the efficiency is merely limited by the low VOC. The origin of VOC in OPV cells is proposed to be created by the energy differ ence between the lowest unoccupied molecular orbital (LUMO) of the acceptor material and the highest occupied molecular orbital (HOMO) of the donor material at the organic heterojunction, i.e. qVOC = EHOMO (donor) – S1ELUMO (acceptor), where q is the electronic charge, EHOMO and ELUMO are the energy levels of photoactive materials , and S1 is the slope of the linear fit. Scharber et al. have systematically studied the dependence of VOC on the bandgap and HOMO levels of 26 conjugated polymers. In particular, a linear fit with slope of unity is obtained, emphasizing the strong coupling of the VOC to the HOMO levels of the conjugated polymers. Based on this linearity model, a maximum power conversion efficiency of bilayer OPV cells as high as 16% can be realized. Therefore, an increase in VOC creates a new dimension for substantial efficiency improvement. This linearity model is valid for most of the conjugated polymeric OPV systems. However, this simple physical principle cannot satisfactorily explain the observed VOC under certain circumstances, especially for the small-molecular based OPV cells. Recently, Kim et al. demonstrated that the VOC can be effectively tailored by controlling the anode work function, in which the VOC of the fluorinated device (0.57 V) is ~50% higher than that of untreated one (0.39 V). The increase on VOC may be attributed to the reduction of hole injecti on barrier at the anode/donor interface. Similar VOC dependence can be observed via using different exciton blocking layers or metal fluorides inserted between the acceptor and the metal cathode. Particularly the thickness of metal fluoride is a crucial factor determining the VOC of the devices. These findings suggest that the linearity model may not be applicable for the small-mo lecular based OPV systems, and other important factors, such as the choice of electrode materials, device structures, are needed to be considered. Indeed, there has long been a controversy about the origin of the VOC of the OPV cells and a complete explanation is definitely needed. The proposed project is designed to deepen our understanding of the physics governing VOC of the small-molecular based OPV devices and derive its relation with the material parameters and device architecture. More specifically, this project aims to i) Identify crucial factors, including electron energy levels, molecular packing of photoactive materials, and device structures, determining the VOC of OPV devices; ii) Investigate the effects of thermal treatment on the device performance; iii) Determine ideal material parameters and device structures for attaining the maximum VOC; iv) Develop feasible approaches for improving the VOC and therefore the performance of OPV devices. |
| Project Title: | White organic light-emitting devices by utilizing exciplex emission |
| Investigator(s): | Chan MY |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 05/2009 |
| Completion Date: | 10/2010 |
| Abstract: |
| Organic light-emitting devices (OLEDs) have become a viable technology for flat panel display after intens ive research and progress in the past decade. In particular, white OLEDs (WOLEDs) draw special attention because of its great potential for solid-state lighting. Recently, many display companies, such as Philip Lighting, Universal Display Corporation, Konica Minolta, have already put on efforts on the development of efficient WOLEDs. WOLEDs provide distinct advantages, including light weight, flexibility, potentially cheap fabrication cost, and most importantly, an extremely high power efficiency over the incandescent and fluorescent lamps. Theoretically, the power efficiency of WOLEDs can reach up to 150 lm/W, doubling that of fluorescent lamp. WOLEDs can be achieved by a combination of two or three colors, i.e. red (R), green (G), and blue (B), in a multi- or single-layer structure. Various strategies, including the development of high performance electroluminescent materials, the use of down-convers ion phosphors, and the utilization of light out-coupling layers, have been reported to produce white light. Among these approaches, electrophosphorescence is the most effective due to its demonstrated potential for achieving 100% internal quantum efficiency. In particular, phosphorescent molecules can harvest all triplet and singlet excitons generated by electrical injection, corresponding to a fourfold increase in efficiency compared to that achievable in single-harvesting fluore scent OLEDs. More recently, Konica Minolta demonstrates a highly efficient WOLED with power efficiency of 64 lm/W using novel phosphorescent emitting materials and optical enhancement structure. This WOLED offers a pleasing white light emission with the Commission Internationale de L’Éclairage (CIE) coordinates of (0.37, 0.41) and the color rendering index (CRI) of 81, which is sufficiently high enough to compete with the existing light sources. Particularly CIE coordinates reflects the eye response of standard observes on three specific wavelengths of lights in the RGB regions; while CRI is a quantitative measure of the ability of the light source to accurately render the color objects. For solid-state lighting, it is preferable to have a “warmer” white light with CIE coordinate of (0.33, 0.33) and high CRI (>80). On the other hand, this device structure employs RGB phosphorescent dopants in separate hosts, in which the stepped progression of highest occupied molecular orbital (HOMO) levels of the hosts effectively reduces the triplet-triplet annihilation. This, in turn, is crucial to rationally design and synthesis new host materials with suitable triplet energies. It is worth noting that device perf ormance of all phosphorescent OLEDs is strongly dependent on the chosen host materials, provided that host materials must have higher triplet energies than those of emitting guest molecules. However, it is quite difficult to design and synthesize host materials for blue phosphore scent dopants, in which host materials with high triplet energies (> 3 eV) are required. In addition, inter-dopant energy transfer is a key problem, in which triplets from the blue phosphor are easily transferred to the phosphorescent green and red, leading to an imbalance in color quality. In order to produce a satisfactory white light emission with optimum color rendition, careful control on minute dopant concentrations (usually 1%) and emissive layer thickness is necessary. This inevitably complicates device fabrication process and increases the manufacturing cost. The use of exciplex emission is another effective approach for achieving white light. Exciplex is an excited state resulting from the coupling of an excited molecule with another molecule in its ground states, and is usually occurred at the organic/organic interface, provided that the hole-transporting material, HTM, (or electron-transport ing material, ETM) must has a strong electron-donating (or accepting) property. Through radiative relaxation, exciplex leads to featureless, red-shifted emission spectra relative to those of individual components. This provides a simple means for tailoring the device color and also for generating white light; particularly no delicate control on dopant concentration is needed. In fact, exciplex emissions have been recently used for producing WOLEDs, in which such emission not only broadens the electroluminescent spectra, but also improves the color purity and CRI. However, the external quantum efficiencies of the exciplex-based devices reported so far are usually very low ( <0.5%). Indeed, from the view of device efficiency, exciplex emission should be avoided. This inevitably wanes the commercial interest in this field. Meanwhile, the PI has recently demonstrated a highly efficient WOLED by utilizing exciplex emission. White light is achieved by the combination of intrinsic emission from the blue light-emitting material 4,4’,4”-trispyrenylphenylamine (TPyPA) and the yellow exciplex emission formed at the TPyPA/ETM interface. This non-doped trilayer device exhibits excellent color purity with CIE coordinates of (0.31, 0.35) over a wide range of luminance from 100 to 20,000 cd/m^2, an exceptionally high power and external quantum efficiencies of 9.0 lm/W and 3.93%, respectively. These are the highest values ever reported for small-molecular based fluorescent WOLEDs. The preliminary results suggest that these extremely high device effi ciencies are governed by the high photoluminescence (PL) quantum yield of TPyPA and balanced electron-hole pairs at the exciplex forming interface. However, the exact mechanisms and physics for the improved performance enhancement are still unclear. Nevertheless, contrary to the common belief, the present results demonstrate that poor performance for the exciplex-based devices is not an inherent problem, and this definitely opens up a new dimension for achieving highly efficient WOLEDs. The proposed project is designed to fully utilize exciplex emission for achieving white light emission and develop feasible approaches for improving the performance of WOLEDs. More specifically, the project aims to i) Explore different combinations of organic materials which favor exciplex formation, and their effects on the device performance; ii) Identify important material parameters governing the performance, including the power efficiency, color purity, and CRI, of exciplex-based WOLEDs; iii) Determine ideal material parameters and device architectures for attaining the maximum power efficiency and CRI of exciplex-based WOLEDs; iv) Provide basis for material design and selection for improving the performance of exciplex-based WOLEDs. |
| Project Title: | Preparation and Characterization of Metal-doped Organic Thin Films for Tandem Organic Light Emitting Devices |
| Investigator(s): | Chan MY |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2010 |
| Abstract: |
| 1) To characterize the effects of the reactivity and concentration of metal dopant on the optical properties of metal-doped organic thin films. In particular, the optical properties (including optical bandgap, absorption coefficient, and transmittance) will be systematically studied. 2) To evaluate the effectiveness of different metal-doped organic layers as connecting units in tandem OLEDs. 3) To provide selection rules for controlling the optical properties of metal-doped organic thin films and for improving the performance of tandem OL EDs. |
| Project Title: | Performance improvement in small-molecular based organic photovoltaic devices by doping near-infrar ed sensitive materials |
| Investigator(s): | Chan MY |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 05/2010 |
| Abstract: |
| Photovoltaics (PV) comprise the technology to convert sunlight directly into electricity. The term “photo” means light and “voltaic” means electricity. A PV cell, also known as “solar cell”, is primarily constructed of inorganic semiconductor that generates electricity when sunlight falls on it. Nowadays, most of PV cells are silicon-based, in which their power conversion efficiencies (i.e. efficiency to convert incident solar power to useful electric power) achieve up to 24%. Because of their safe, environmentally friendly, and unlimited availability benefits, PV cells have found applications in customer electronics, like watches and calculators, small scale remote residential powe r systems, as well as highway signs in USA and Canada. The standard silicon-based PV technology reaches its mature stage; however, it is still difficult and very expensive to produce efficient silicon-based PV devices, especially for large surface area, due to problems in producing large Si crystals without significant efficiency-degrading defects. Currently, solar generating power is four to six times more expensive to customers than coal generating power. There is a prevailing need for the development of new materials and concepts for photovoltaic energy conversion that could potentially reduce the manufacturing cost of PV cells. Development of research in the field of OPV devices has been envisaged as a possible route. OPV cells provide many foreseeable advantages, such as simple fabrication process, light weight, flexibility, and solution-processibility for large area production. OPV cell generally consists of two photoactive organic materials (so called “donor-acceptor” system) sandwiched between two conducting electrodes. Under light illumination, excitons are generated in the photoactive layers and some would dissociate into electrons and holes at the donor/acceptor heterointerfaces. These charge carriers are subsequently collected at the respective electrodes, contributing to the photocurrent. At the same time, other excitons may diffuse to the cathode and decay non-radiatively via quenching, which substantially lowers the quantum efficiency. Many approaches have been attempted to improve the device performance, including the introduction of mixed donor-acceptor heterojunctions, multiple heterojunctions, triplet photoactive materials, and light-harvesting structures. Encouraging progress with power conversion efficiencie s up to 6% has been recently reported by utilizing tandem device architecture, i.e. stacking two polymeric OPV devices vertically in series; however, this efficiency is still not sufficient to meet the realistic specifications for commercialization. One of the major obstacles for achieving high power conversion efficiency is the limited spectral overlap between the absorption of photoactive materials and the solar spectrum, resulting in a low photocurrent. Indeed, over 60% of the total solar photon flux is at wavelengths λ > 600 nm with approximately 50% in the red and near-infrared (NIR) spectrum at 600 < λ < 1000 nm. However, the optical bandgap of most organic photoactive materials is not optimized with respect to the solar spectrum, in which only 20 ~ 30% of solar spectrum can be absorbed. For instance, copper phthalocyanine (CuPc), a commonly used donor material in OPV devices, has an absorption spectrum that falls off at λ > 700 nm. This suggests that new materials need to be developed that can absorb NIR radiation, and effectively convert the absorbed photons into current. Several attempts have been made with various classes of polymers to attain a NIR contribution to the photocurrent by narrowi ng the polymer bandgap. Hou et al. recently demonstrated an efficient NIR absorbing OPV device by using their home-made poly[(4,4’-bis(2-ethylhexyl)dithieno[3,2-b:2’,3’-d]silole-2 ,6-diyl-alt-(2,1,3-benzot (PSBTBT). Such device exhibited a high power convers ion efficiency of 5.1% under 1 sun illumination with spectral response extending up to 800 nm. Unfortunately, efficient OPV devices based on small-molecular materials have not yet been realized. Rand et al. have reported the use of tin phthalocyanine (SnPc) inserted between the CuPc and fullerene (C60) to broaden the spectral cove rage up to 1000 nm. However, the major limitation on the use of SnPc layer is its relatively low carrier mobility. Particularly when the layer thickness is larger than 5 nm, both photocurrent and fill factor (FF) of the devices drop significantly, posing an upper limit of power conversion efficiency (~1.3%). Meanwhile, the PI has studied the effects of dye sensitization on the performance of OPV devices, in which the fluoresce nt dye (rubrene) is used as sensitizing material and doped into the donor and/or the acceptor layer. It is found that doping of rubrene not only broadens the spectral coverage, but also forms bulk heterojunction with the donor or acceptor material. In particular, bulk heterojuncti on is an intimate mixture of donor and acceptor via blending polymers or co-evaporating organic materials simultaneously. Bulk heterojunction creates a spatially distributed donor–acceptor interface, where all excitons formed can be efficiently dissociated into free charge carrier s to contribute the photocurrent. This doping technique opens up a possibility to use fluorescent dyes for maximizing absorption spectral coverage as well as increasing photon harvesting. The proposed project is designed to fully exploit whether the dye doping technique can be applied by using NIR sensitive small-molecular materials. More specifically, this project aims to i) Identify important factors, including physical, chemical, and electronic properties, of NIR sensitive organic materials, determining the photovoltaic response of small-molecular based OPV devices; ii) Investigate the effects of thermal treatment on the device performance; iii) Determine ideal material parameters and device structures for attaining the maximum power conversion efficiency; iv) Develop feasible approaches for improving the performance of small-molecular based OPV devices by doping techniq ues. |
| Project Title: | The International Conference on Nanophotonics 2010 Host engineering for triplet exciton confinement in blue phosphorescent organic light emitting devices |
| Investigator(s): | Chan MY |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 05/2010 |
| Completion Date: | 06/2010 |
| Abstract: |
| N/A |
| List of Research Outputs |
| Lai S.L., Lo M.F., Chan M.Y. , Lee C.S. and Lee S.T., Impact Of Dye Interlayer On The Performance Of Organic Photovoltaic Devices, Applied Physics Letters . 2009, 95: 153303-1 to 153303-3. |
| Tong Q.X., Chan M.Y. , Lai S.L., Ng T.W., Wang P.F., Lee C.S. and Lee S.T., High-efficiency Undoped Blue Organic Light-emitting Devices, Dyes and Pigments . 2010, 86: 233-237. |
| Researcher : Chan OY |
| List of Research Outputs |
| Ho C.M. , Zhang J.L., Zhou C. , Chan O.Y. , Yan J. , Zhang F.Y., Huang J.S. and Che C.M. , A Water-Soluble Ruthenium Glycosylated Porphyrin Catalyst for Carbenoid Transfer Reactions in Aqueous Media with Applications in Bioconjugation Reactions, Journal of the American Chemical Society . 2010, 132: 1886-1894. |
| Researcher : Chan PWH |
| Project Title: | Synthesis and applications of transition metal-nitrogen multiple bonded complexes in carbon-nitr ogen bond formation reactions |
| Investigator(s): | Chan PWH, Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 11/2004 |
| Abstract: |
| To develop the chemistry of highly reactive metal-nitroge n multiple bonded complexes. |
| Researcher : Chan QKW |
| List of Research Outputs |
| Lai S.W. , Chan Q.K.W. , Han J. , Zhi Y.G. , Zhu N. and Che C.M. , Cyclometalated Pt(II) Complexes bearing Phosphinated Calix[4]arenes, The Sixth National Conference on Coordination Chemistry, The University of Hong Kong, Hong Kong, P. R. China, 6-9 July . 2009. |
| Researcher : Chan TW |
| List of Research Outputs |
| Song H.O., Chan T.W. , Li M. , Wong M.C. , Yam V.W.W. and Wu L.X., Synthesis, Characterization and Fluorescence Resonance Energy Transfer (FRET) Studies of Rhenium(I) Complexes With Coumarin Pendants, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P210. |
| Yam V.W.W. , Song H. , Chan T.W. , Zhu N. , Tao C.H. , Wong M.C. and Wu L.X., Synthesis, Characterization, Ion-Binding Properties, and Fluorescence Resonance Energy Transfer Behavior of Rhenium(I) Complexes Containing a Coumarin-Appended 2,2′-Bipyridine, Journal of Physical Chemistry C . 2009, 113: 11674-11682. |
| Researcher : Chan WK |
| Project Title: | 232nd American Chemical Society National Meeting Synthesis and Characterization of One-Dimensional Ruthenium-Based Self-Assembly Polym er |
| Investigator(s): | Chan WK |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 09/2006 |
| Completion Date: | 09/2009 |
| Abstract: |
| N/A |
| Project Title: | Synthesis of photosensitizing molecules with low absorption energy |
| Investigator(s): | Chan WK |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 11/2007 |
| Completion Date: | 10/2009 |
| Abstract: |
| 1. To synthesize a series of molecular and polymeric materials that exhibit low absorption energy in the visible region. 2. To investigate the optical absorption properties of the target materials by various physical characterization techniques. 3. To explore the potentials of using the products as photosensitizers in organic photovoltaic cells. |
| Project Title: | Design and synthesis of multifunctional polymers and their applications in photovoltaic devices |
| Investigator(s): | Chan WK |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 11/2007 |
| Abstract: |
| To design, synthesize, and characterize various types of multifunctional conjugated and non-conjugat ed polymers that contain sensitizers and charge carrying units in a single polymer molecule. To fabricate the polymer into photovoltaic devices by different film forming techniques and to measure the photovoltaic device performance. To study the relationship between the physical properties of the polymers and the post film forming treatments such as annealing. |
| Project Title: | Development of Photosensitizers With Broad Optical Absorption For Photovoltaic Applications |
| Investigator(s): | Chan WK |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 10/2008 |
| Abstract: |
| 1) To synthesize and characterize conjugated polymers incorporated with electron donor and acceptor units that exhibit intramolecular charge transfer properties. 2) To synthesize and characterize conjugated polymers functionalized with pendant photosensitizers. 3) To synthesize and characterize dinuclear metal complex sensitizers that exhibit broad absorption in the vis ible region. 4) To fabricate photovoltaic cells and dye-sensitized solar cells with the materials synthesized and to optimize the device performances. |
| Project Title: | Tuning of absorption energy in metal complex dyes for dye-sensitized solar cells |
| Investigator(s): | Chan WK |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 11/2008 |
| Abstract: |
| 1. To design and synthesize new polymeric and molecular metal complex dyes as the photo sensitizers in dye-sensitized solar cells. 2. To investigate to relationship between the structure property relationship of these new compounds, particularly on their optical absorption and electrochemical properties. 3. To fabricate dye-sensitized solar cells based on the new compounds synthesized, and to test the performance of these devices. |
| Project Title: | Development of functional transition metal supramolecules for the fabrication of photovoltai c cells by self-assembly method |
| Investigator(s): | Chan WK |
| Department: | Chemistry |
| Source(s) of Funding: | Travel Grants for NSFC/RGC JRS |
| Start Date: | 12/2008 |
| Abstract: |
| Travel Grants for NSFC/RGC JRS |
| Project Title: | 238th National Meeting of the American Chemical Society Functional metal containing block copolymers and their applications |
| Investigator(s): | Chan WK |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 08/2009 |
| Completion Date: | 08/2009 |
| Abstract: |
| N/A |
| Project Title: | Applications of carbon nanotubes-polymer composites in optoelectronics |
| Investigator(s): | Chan WK |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 02/2010 |
| Abstract: |
| 1. To synthesize a series of block copolymers fu nctionalized with photosensitizers/charge transport units. 2. To prepare polymer-carbon nanotube composites by anchoring the polymers obtained on carbon nanotube by non-covalent interactions. 3. To investigate the potentials of using the composite materials as the active layers in various opto-electronic devices. |
| List of Research Outputs |
| Chan W.K. , Mak S.K. , Tam W.Y. and Leung Q.Y. , Functional Polymers For Photovoltaic Applications, The 9th International Symposium on Advanced Organic Photonics (ISAOP-9), Bunratty, Ireland . 2009. |
| Chan W.K. , Functional metal containing block copolymers and their applications, American Chemical Society 236th National Meeting, Washington DC, USA . 2009. |
| Chan W.K. , Metal containing polymers for photovoltaic applications, International Conference on Green & Sustainable Chemistry, August 3-5, 2009, Singapore . 2009. |
| Chan W.K. , Synthesis of Metal Containing Aromatic Polyamides and Polyesters and Their Properties, 6th International Symposium on Polyimides and Other High Temeprature/High Performance Polymers, Melbourne , Florida, USA. . 2009. |
| Chan W.K. , Transition-metal complexes photosensitizing organic solar cells, SPIE Newsroom . International Society For Optics and Photonics, 2009. |
| Chen X. , Yip C.T. , Fung M.K. , Djurisic A. and Chan W.K. , GaN-nanowire-based dye-sensitized solar cells, Applied Physics A: Materials Science & Processing . Springer, 2010, 100: 15-19. |
| Chen X. , Ng M.C.A. , Fang F. , Djurisic A. , Chan W.K. , Tam H.L., Cheah K.W., Fong P.W.K., Lui H.F. and Surya C., The influence of the ZnO seed layer on the ZnO nanorod /GaN LEDs, Journal of the Electrochemical Society . The Electrochemical Society, 2010, 157: H308-H311. |
| Lam R.W.M. , Wong C.T. , Li Z. , Luk K.D.K. , Cheung K.M.C. , Chiu P.K.Y. , Xu B., Chan W.K. , Fang D. , Leong J.C.Y. and Lu W.W. , 252. L-Asparagine on strontium hydroxyapatite nanorods morphology and biocompatibility , International Journal of Biomedical Engineering and Technology . 2009, 2(4): 303-318. |
| Lam R.W.M. , Pan H. , Li Z. , Chen Y., Chan W.K. , Wong C.T. , Luk K.D.K. and Lu W.W. , Fatty acid affects the nucleation of strontium-substituted biominerals, Ceram Int . 2010, 36(2): 683-688. |
| Lam W.M.R. , Pan H. , Li Z. , Yang C., Chan W.K. , Wong C.T. , Luk K.D.K. and Lu W.W. , Strontium-substituted calcium phosphates prepared by hydrothermal method under linoleic acid-ethanol solution, CERAMICS INTERNATIONAL . 2010, 36(2): 683-688. |
| Mak S.K. and Chan W.K. , Applications of Metal Containing Polymers in Organic Solar Cells, In: A. S. Abd-El-Aziz, C. E. Carraher, C. U. Pittman, M. Zeldin, Macromolecules Containing Metal and Metal-like Elements, Volume 10: Photophysics and Photochemistry of Metal-Containing Polymers . Hoboken, John Wiley and Sons Inc., 2010, 159-185. |
| Mak S.K. , Cheung W.K. , Leung Q.Y. and Chan W.K. , Conjugated Copolymers Containing Low Bandgap Rhenium(I) Complexes, Macromolecular Rapid Communications . Wiley-VCH, 2010, 31: 875-882. |
| Mak S.K. , Wong H.L. , Leung Q.Y. , Tam W.Y. , Chan W.K. and Djurisic A. , The use of sublimable chlorotricarbonyl bis(phenylimino)ace naphthene rhenium(I) complexes as photosensitizers in bulk-heterojunction photovoltaic devices, Journal of Organometallic Chemistry . ELSEVIER SCIENCE SA, 2009, 694: 2770-2776. |
| Mak S.K. , Leung Q.Y. , Li C.H. and Chan W.K. , Tuning the Electronic Properties of Conjugated Polymer by Tethering Low-Bandgap Rhenium(I) Complex on the Main Chain, Journal of Polymer Science Part A: Polymer Chemistry . Wiley Periodicals, Inc., 2010, 48: 2311-2319. |
| Ng M.C.A. , Xi Y. , Hsu Y.F. , Djurisic A. , Chan W.K. , Gwo S., Tam H.L., Cheah K.W., Fong P.W.K., Lui H.F. and Surya C., GaN/ZnO nanorod light emitting diodes with different emission spectra, Nanotechnology . Bristol, IOP Publishing Limited, 2009, 20: 445201: 1-8. |
| Tong W.Y. , Chen H.Y., Djurisic A. , Ng A.M.C. , Wang H. , Gwo S. and Chan W.K. , Infrared photoluminescence from α- and β-copper phthalocyanine nanostructures, Optical Materials . Amsterdam, Elsevier B.V., 2010, 32: 924-927. |
| Wang X.Z., Wang Q.W., Yan L., Wong W.Y., Cheung K.Y. , Ng A. , Djurisic A. and Chan W.K. , Very-low-bandgap metallopolyynes of platinum with a cyclopentadithiophenone ring for organic solar cells absorbing down to the near-infrared spectral region, Macromolecular Rapid Communications . Weinheim, WILEY-VCH Verlag GmbH & Co. KGaA, 2010, 31: 861-867. |
| Wong W.Y., Chow W.C., Cheung K.Y. , Fung M.K. , Djurisic A. and Chan W.K. , Harvesting solar energy using conjugated metallopolyyne donors containing electron-rich phenothiazine-oligothiophene moieties, Journal of Organometallic Chemistry . Amsterdam, Elsevier B.V., 2009, 694: 2717-2726. |
| Xi Y. , Huang B. , Djurisic A. , Chan M.N. , Leung F.C.C. , Chan W.K. and Au D.T.W., Electrodeposition for antibacterial nickel-oxide-based coatings, Thin Solid Films . Amsterdam, Elsevier B.V., 2009, 517: 6527-6530. |
| Researcher : Chan WS |
| List of Research Outputs |
| Ma C. , Kwok W.M. , Chan W.S. , Du Y. , Zuo P. , Kan T.W. , Toy P.H. and Phillips D.L. , Time-Resolved Spectroscopy Studies of the Photodepro tection Reactions of p -Hydroxyphenacyl Ester Phototrigger Compounds, Current Science . 2009, 97: 202-209. |
| Researcher : Chan WT |
| Project Title: | Study of sorption of heavy metals on individual cells of Chlorella vulgris by time-resolved Inductively Coupled Plasma-Mass Spectrometery |
| Investigator(s): | Chan WT |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 07/2007 |
| Abstract: |
| Algae are effective agent for bioremediation of the environment. The sportion capacity of heavy metals by algae is in the range of 0.1 to 10 mmol/g [1]. The metals are taken up at the cell surface via biosorption and/or internally via metabolic uptake [2]. The algae surface is populated with functional groups for metal binding. These groups include hydroxyl, carbonyl, carb oxyl, sulfhydryl, thioether, sulfonate, amine, imine, amide, imidazole, phosphonate, and phosphodiester [3]. Biosorption on the cell surface is mainly an ion exchange process. Studies on the adsorption equilibrium and kinetics for various combinations of metals and algae have been reported [4,5]. The adsorption process is rapid but is sensitive to ambient conditions such as pH, ionic strength, and the presence of organic and inorganic ligands. The adsorbed metals may leach back into the environment if the ambient conditions change. Live cells may, therefore, offer advantages in bioremediation [2]. Active and growing cells may incorporate the metals into vacuoles and other intracellular sites of the cells and the metals are not readily released back to the environment. Live cells may also exhibit selectivit y towards certain metals or metal species. Literature methods for sorption study typically involve measurement of the bulk metal contents in the supernatant of the algae-metal solution mixture or the digested algae [6]. The required volume of the sample solution and/or the quantity of the algae are relatively large. Kinetics study is also limited by the multi-step sample treatmen t before measurement (i.e., centrifugation/filtration and/or digestion). The methods are inherently slow and are not adequate to follow fast events. Sophisticated methods such as electron microscopy (EM) and x-ray fluorescence microbeam analysis are available for the determination of metal distribution in a cell [7]. However, measurement of a large number of cells using the methods is inefficient. We plan to study the adsorption capacity and kinetics of heavy metals by live green algae using time-resolved inductively coupled plasma-mass spectrometry (ICP-MS). We will use Chlorella vulgris as a model. Chlorella vulgris is a type of small unicellar green algae, of diameter of approximately 10 micrometers. Aqueous solutions containing live cells of the algae will be rendered into a fine mist by conventional solution nebulization methods, such as pneumatic nebulization via a V-groove nebulizer. The cells are entrained individually in the solution aerosols if the number density of the algae in the original solution is sufficiently low. Our preliminary data show that cell number density of 10^6 /mL or below is adequate. The aerosols and the cells are readily transported to the ICP by a stream of argon carrier gas. As the cells enter the ICP individually, ions plumes corresponding to each cell are formed in the ICP. For sample solution of low algal cell number density, the plumes are separated from each other in the central channel of the ICP. The metal ions in each plume are readily detected using time-resolved ICP-MS as a current spike of duration of 100 microseconds [8]. The proposed method will be the first method to measure the metal content of individual algal cells with a relatively high sampling frequency of more than 10 cell/s. The time resolution for kinetics study of metal adsorption by the cells will be in the range of tens of seconds instead of minutes of the conventional bulk methods. Adsorption of metals onto the green algae can also be used as a preconcentration method of trace metals of concentration of part-per-trillion level. We have successfully used iron oxide nanoparticles and oxidized form of carbon nanotubes for metal preconcentration [8,9]. The preconcentrated metals on the particles are measured using time-resolved ICP-MS as current spikes. The signal-to-background ratios (SNR) of the current spikes are significantly larger than that of the bulk solution. The detection limits of metal determination are reduced. The adsorption capacity of Chlorella vulgris for heavy metals is large [1] and the size of the algae is relatively large compared to the nanoparticles (10 μm versus 100 nm). Chlorella vulgris is potentially a “super adsorbent” for trace metal preconcentration. Significant reduction in ICP-MS detection limits is expected. Preconcentration of metals by live cells may offer another advantage that the metals are taken up irreversibly [2] and the metals will not be lost from the cells by further treatment of the cells, e.g., filtration and washing. The objectives of the research proposal are summarized below. 1. To develop a rapid method for the determination of the metal sorption capacity and kinetics of green algae based on ICP-MS measurement of the quantity of heavy metals in indiv idual algal cells. 2. To determine the feasibility of using algae as adsorbent particles for metal preconcentration for chemical analysis. Time-resolved measurement of the preconcentrated metals on individual cells may reduce the ICP-MS detection limits by orders of magnitude. References: 1. S.K. Mehta and J.P. Gaur, “Use of Algae for Removing Heavy Metal Ions from Wastewater: Progress and Prospects”, Critical Reviews in Biotechnology 2005, 25, 113-152. 2. A. Malik, “Metal bioremediation through growing cells”, Evironment International 2004, 30, 261-278. 3. R.H.S. Vieira and B. Volesky, “Biosorption: a solution to pollution?”, Internatl. Microbiol. 2000, 3, 17-24. 4. T.A. Davis, B. Volesky, and A. Mucci, “A review of the biochemistry of heavy metal biosorption by brown algae”, Water Research 2003, 37, 4311-4330. 5. F.A. Abu Al-Rub, M.H. El-Naas, F. Benyahia, and I. Ashour, “Biosorption of nickel on blank alginate beads, free and immobilized algal cells”, Process Biochemistry 2004, 39, 1767-1773. 6. S.K. Mehta and J.O. Gaur, “Concurrent sorption of Ni2+ and Cu2+ by Chlorella vulgaris from a binary metal solution”, Appl. Microbiol. Biotechnol. 2001, 55, 379-382. 7. “Bioremediation of metals and radionuclides”, 2nd edition (2003) by The National and Accelerated Bioremediation Research Program, Office of Biological and Environmental Research, Office of Science, US Department of Energy. http://www.lbn l.org/NABIR/generalinfo/primers_guides/03_ accessed on November 15, 2006. 8. M.H.P. Yau and W.T. Chan, “A Novel Detection Scheme of Trace Elements Using ICP-MS”, J. Anal. At. Spectrom. 2005, 20, 1197-1202. 9. M.H.P. Yau, “Preconcentration of trace metals on nanoparticles for time-resolved ICP-MS measurement”, PhD thesis, The University of Hong Kong (2006). |
| Project Title: | Ultrasonic emulsification of oil in water for rapid determination of trace metals in oils |
| Investigator(s): | Chan WT |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 12/2008 |
| Completion Date: | 11/2009 |
| Abstract: |
| Determination of metal contents in various types of oil is required for a wide range of industrial processes. The presence of metals in oil is also of significant environmental and health concerns. For example, trace element contents in crude oil are important geochemical characteristics of source rocks and basins. High concentration of Ni and V in crude oil may contribute to environment al pollution. Wear metals monitoring in lubricating oil is required for routine maintenance of aircraft and railroad engines to avoid catastrophic failure of the mechanism. Trace elements in edible seed oils and seeds are essential elements and important constituents of naturally occurring antioxidants, as well as markers of potential environmental contamination. Development of fast and accurate analytical methods for the determin ation of trace elements in oils is a continuous quest of analytical scientists [1-4]. Oil samples are not analyzed directly for several reasons. The oil matrix cannot be atomized effectively in common atomizers when a large quantity of oil is introduced in an atomizer, e.g., the inductively coupled plasma (ICP), flame or the graphite furnace. Carbon residues formed in the atomizer tend to interfere with the metal measurements. Standard methods of sample preparation include dry ashing of the samples in open crucible, wet ashing in acids, and microwave digestion. The methods involve addition of a large quantity of solvents to the sample and require multiple steps in sample preparation. Alternatively, oil samples can be prepared as emulsions or microemuls ions. The oil sample is evenly dispersed in water as microdroplets with the aid of a surfactant or a co-solvent. Emulsification of oil samples allows direct injection of the sample into an atomizer without the tedious sample preparation steps. We propose to further improve the emulsification method using ultrasonic dispersion of oil in pure water. No surfactants or organic co-solvents are used. Introduc tion of a large quantity of organic compounds (surfactants) or organic solvents into an atomic source such as the ICP is not desirable. The excitation conditions of the atomic source are changed, resulting in matrix effects in the plasma. The efficiency of sample transport for aqueous standards and organic-rich samples can also be significantly different. Calibration using matrix-matched standards (e.g., organometallic compounds in oil) is, therefore, required. The cost of analysi s will, therefore, increase. The use of organic solvents is also not desirable in the view of the practice of green chemistry. It is a common sense that oil and water do not mix readily. A mixture of oil and water forms an emulsion momentarily upon rigorous mixing (e.g., by ultrasonication). But the dispersed oil tends to coalesce into an oil layer rapidly, usually within minutes. However, our preliminary experiments show that stable emulsion of oil in water can be produced readily by injection of an oil sample into water in an ultrasonic bath. The oil-in-water emulsion is stab le for a few hours. Interestingly, the stable emulsion is predicted by the DLVO theory [5]. Each oil droplet carries a negative charge and is repelled from each other. The electrostatic repulsive force is balanced by van der Waals attractive force between the droplets in stable emulsions. The common observation of unstable oil-in-water emulsion is, therefore, not related to the stability of the emulsion, but the method of the preparation of the emulsion. Our preliminary study shows that the injection rate of the oil sample and the position of the injection tube relative to the standing wave of the ultrasound in water are critical for successful production of stable emulsion. The oil sample must be injected slowly into water at the crest of the ultrasound standing wave for efficient dispersion of oil in water to form a stable emulsion. We propose to introduce the oil-in-water emulsion into the ICP directly using conventional solution nebulization methods for the determination of metal contents of oil by inductively coupled plasma-mass spectrometry (ICP-MS). Matrix effects of the oil-in-water emulsion on plasma excitation conditio ns and efficiency of sample transport will be studied. The feasibility of calibration using aqueous standards for oil analysis will be studied. Petroleum oil will be used as a model matrix in this study, but the method can be extended readily to other hydrophobic liquid-phase matrices, e.g., vegetable oil and fine PTFE dispersion. To summarize, the objectives of the project include: 1. Development of a rapid and environment-friendly sample preparation method of oil-in-water emulsion formation using ultrasonication. No organic solvents or strong acids are used. 2. Development of a rapid method for the determination of trace met als in oil using ICP-MS. References: 1. Hervé Lachas, Raphaëlle Richaud, Alan A. Herod, Denis R. Dugwell and Rafael Kandiyoti, “Determination of trace elements by inductively coupled plasma mass spectrometry of biomass and fuel oil reference materials using milligram sample sizes”, Rapid Commun. Mass Spectrom., 2000, 14, 335–343. 2. Roseli M. de Souza, André L.S. Meliande, Carmem L.P. da Silveira, Ricardo Q. Aucélio, “Determi nation of Mo, Zn, Cd, Ti, Ni, V, Fe, Mn, Cr and Co in crude oil using inductively coupled plasma optical emission spectrometry and sample introduction as detergentless microemulsions”, Microchemical Journal, 2006, 82, 137–141. 3. M. Murillo, Z. Benzo, E. Marcano, C. Gomez, A. Garaboto and C. Marin, “Determination of copper, iron and nickel in edible oils using emulsified solutions by ICP-AES”, J. Analyt. Atom. Spectrom., 1999, 14, 815–820. 4. J. H. Taylor, T. T. Bartels, and N. L. Crump, “Behavior of Metal Particles Compared to Organometallic Compounds Measured by Flame Atomic Absorption Spectrophotometr y”, Analytical Chemistry, 1971, 43, 1780 – 1784. 5. R.M. Pashley, “Effect of degassing on the formation and stability of surfactant-free emulsions and fine Teflon dispersions”, J. Phys. Chem. B, 2003, 107, 1714 – 1720. |
| Project Title: | High performance liquid chromatograph y for undergraduate courses on chemical instrumentation and chemical analysis |
| Investigator(s): | Chan WT, Phillips DL |
| Department: | Chemistry |
| Source(s) of Funding: | Leung Kau Kui Research and Teaching Endowment Fund - Teaching Grants |
| Start Date: | 04/2009 |
| Abstract: |
| We plan to upgrade our high performance liquid chromatography (HPLC) setup that is dedicated for teaching with a modern HPLC. Our current HPLC set up is a low cost system with separate components of pump, column, sample injector, light source and detector, and data recorder (a strip chart recorder). The system is unique in that students can see and touch each component of the HPLC which are usually completely enclosed in a box in modern instruments. The experimental set up of the system, from sample injection to eluent detection, is readily understood at a glance. In addition, all operations of the system are manual. Students literally acquire hand-on experience in the operation and optimi zation of HPLC. The system, however, lacks some vital capabilities of modern HPLC. The system can only perform isocratic elution and single-wavelength UV absorption detection. Capability of modern HPLC, such as gradient elution, diode array detection, temperature control, and faci lities to couple the HPLC to a mass spectrometer (MS), are absent. In addition, the system has been used for more than 15 years and requires a lot of maintenance to keep it running. We are now limited to simple experiments such as extraction of phenols from soils and isocratic HPLC separation of the phenols in our Year-2 instrumen tation course (CHEM2202 Chemical Instrumentation). Important techniques of HPLC such as gradient elution and LC-MS that are discussed in the lectures are currently not available to the students. CHEM2202 is the only course on chemical instrumentation for most chemistry students. It is important that students are exposed to modern setup and practice of important instruments in the chemistry laboratory. HPLC is one of these important instruments. Student learning can be substantially improved with a modern HPLC and associated new experiments that make use of the full capacity of the instrument. We plan to acquire an HPLC with gradient elution capability, diode array detector, and facilities for coupling the HPLC to mass spectrometer for positive identification of the analytes. We will develop new experiments to facilitate training of students on current practice in chemical analysis and chemical instrumentation using HPLC and LC-MS. Our target students are both chemistry major and non-major students. The courses for chemistry major include CHEM2202 Chemical Instrumentation, CHEM3203 Analytical Chemistry, CHEM3204 Modern Chemical Instrumentation and Applications, and CHEM2207 Food and Water Analysis. We are also developing a course on chemical instrumentation for non-major student: CHEM2003 Introductory Instrumental Chemical Analysis. The course will be mounted in 2010 for students of Biological Sciences, Pharmacology, and other chemistry-related disciplines such as Environmental Sciences. The new experiments of these courses will correspond to the lecture materials which cover the basic principles and modern approaches of HPLC separation and detection. The samples of the experiment will be selected to cat er for the background and interest of the students. Some of the possible HPLC experiments are identification of amino acids in peptides [1], mapping of protease digestion products [2], quantification of tea flavonoids [3], analysis of α- and β-acids in hops [4], and determination of interesting compounds related to environmental and food sciences, such as pesticides, drugs, food dyes, and melamine. Experiments on optimization of HPLC separations will also be developed for courses on chemical instrumentatio n [5-7]. We also plan to develop experiments on protein analysis using LC-MS, which is a major state-of-the-art method in proteomics. The LC-MS setup will also be valuable to illustrate the principle of positive identification of eluents using mass spectrometry. To summarize, we aim to develop a set of new experiments on HPLC and LC-MS. The sample types will be relevant to the students’ major areas of study and/or of common interests. The experiments will be based on modern methodology and practice of HPLC analysis. Students will acquire hand-on experience in running a modern HPLC instrument and application of standard methods for the analysis of various kinds of samples such as peptides from tryptic digested proteins, melamine in food products, and PAH in soils. We aim to set up laboratory classes that provide proper and satisfactory learning experience for the students. The training will be valuable for students taking up career in the industry as well as further study in science. References: 1. C.H. Clapp, J.S. Swan, J.L. Poechmann, Journal of Chemical Education, 1992, 69, A122-A126. 2. M.M. Vestling, Journal of Chemical Education, 1991, 68, 958-960. 3. J.D. Freeman and E.D. Niemeyer, Journal of Chemical Education, 2008 , 85, 951-953. 4. T.M. Danenhower, L.J. Force, K.J. Petersen, and T.A. Betts, Journal of Chemical Education, 2008, 85, 954-956. 5. D.T. Harvey, S. Byerly, A. Bowman, and J. Tomlin, Journal of Chemical Education, 1991, 68, 162-168. 6. T. Hanai, “HPLC : a practical guide”, Cambridge : Royal Society of Chemistry (1999). 7. M.C. McMaster, “HPLC, a practical user's guide”, Hoboken, N.J. : Wiley-Interscience (2007). |
| Project Title: | Development of cell chip ICP-MS hyphenated technique for massively parallel cell culture and on-line determination of metal contents of individ ual cells |
| Investigator(s): | Chan WT, Lin BC |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2010 |
| Abstract: |
| 1) Development of the cell chip-ICP-MS system. The system includes custom cell chips for parallel experiments on microorganism-metal interactions, cell chip-ICP-MS interface, and a commercial ICP-MS. The operating parameters and procedures of the system will be optimized. The method of time-resolved ICP-MS will be adapted for single cell analysis using the cell chip-ICP-MS system. 2) Application of cell chip-ICP-MS for the study of the interactions of microorganisms and metal ions. The metal uptake rate, sorption capacity, and toxicity of metals on the microorganism will be studied. |
| List of Research Outputs |
| Ho K.S. and Chan W.T. , Time-resolved ICP-MS Measurement of Metals in Single-cell Algae, Colloquium Spectroscopicum Internationale XXXVI, Budapest, Hungary, August 30 - September 3, 2009 (Oral presentation) . 2009. |
| Lui K.O. and Chan W.T. , Single Particle Analysis using Time-resolved ICP-MS, Colloquium Spectroscopicum Internationale XXXVI, Budapest, Hungary, August 30 - September 3, 2009 (Or al presentation) . 2009. |
| Yeung S.L. , Cheng C.W., Lui K.O. , Tsang J.S.H. , Chan W.T. and Lim B.L. , Purple acid phosphatase-like sequences in prokaryotic genomes and the characterization of an atypical purple alkaline phosphatase from Burkholderia cenocepacia J2315, Gene . 2009, 440: 1-8. |
| Researcher : Che CM |
| Project Title: | Blue light photoluminescent materials |
| Investigator(s): | Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Hung Hing Ying Physical Sciences Research Fund |
| Start Date: | 02/1999 |
| Abstract: |
| To design and prepare highly robust and luminous materials for fabrication of bright blue-light emitting diode (LED) devices. |
| Project Title: | Institute of molecular technology for drug discovery and synthesis |
| Investigator(s): | Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Areas of Excellence Scheme |
| Start Date: | 11/2001 |
| Abstract: |
| To pursue world-class fundamental research in Ch emical Biology; to develop novel compounds for new medicine and to engender the development of local and regional pharmaceutical industries through high quality research. |
| Project Title: | Research and development of lumines cent biosensors for drug screening and environmental monitoring |
| Investigator(s): | Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Applied Research |
| Start Date: | 11/2002 |
| Abstract: |
| To optimize the luminescent materials developed by Che and co-workers for optical pH, oxygen and chlorinated hydrocarbons sensing technology; to fabricate optical biosensors using the newly developed luminescent mate rials; to apply the newly developed fluorescent pH/oxygen biosensors for cell viability assay, drug screening and monitoring of environmental pollutants. |
| Project Title: | Functional nanomaterials research |
| Investigator(s): | Che CM, Chan MCW |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 11/2003 |
| Abstract: |
| To develop new nanostructured and nanocomposite materials, based on the existing research expertise in synthetic chemistry, semiconductors, and ongoing collaborations with Chinese Academy of Sciences; to identify practical applications for newly prepared and patentable nanomaterials, such as catalysts for green chemistry and nanodevices for organic optoelec tronics; to enable HKU to develop into a leading institution in nanosciences. |
| Project Title: | Reactive metal-oxo complexes of group VIII metals for organic oxidations |
| Investigator(s): | Che CM, Wong MK, Tong SM |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2007 |
| Completion Date: | 12/2009 |
| Abstract: |
| This project aims to establish an interdisciplinary research program to expand the scope of research in metal-catalyzed organic oxidations previously developed in the laboratories [The University of Hong Kong and Shanghai-Hong Kong Joint Laboratory on Chemical Synthesis] of the HKU team. Synergetic efforts would be made to employ metalloporphyrins as key catalysts in organic synthesis, develop practical iron catalysts for organic oxidations, the latter is an area receiving a rapidly growing attention after the recent works of Que and co-workers (Science, 2003, 299, 1037), development of alternative and inexpensive catalysts for cis-dihydroxylation of alkenes and green oxidation catalysis. In essence, the objectives include. (1) To develop metalloporphyrin-c atalyzed alkyne oxidations for biomolecule modification and practical protocols for construction of synthetically useful epoxides using environmentally friendly oxidants. (2) To develop ruthenium-catalyzed organic oxidations using air or hydrogen peroxide as a terminal oxidant. Of particular interest is to develop the chemistry of ruthenium-catalyzed Wacker oxidation of alkenes to aldehydes recently discovered at Shanghai-Hong Ko ng Joint Laboratory on Chemical Synthesis. (3) To develop practical iron catalysts using oligopyridine ligand systems for organic oxidations. (4) To design new classes of ruthenium-oxo complexes including those containing chiral auxiliary ligands for cis-dihydroxylation of alkenes. This work also aims to inquire as to whether a cis-dioxometal unit is a necessary requisite to acc omplish cis-dihydroxylation of alkenes. (5) To develop supported metal catalysts including those containing ruthenium nanoparticles for organic oxidations. This project is a concerted effort to tackle some difficult problems in the field of organic oxidations. Completion of this project could lead to important findings in ruthenium-catalyzed organic oxidations using air or hydrogen peroxide as a terminal oxidant. The outcomes would be rewarding as inexpensive and green oxidation technologies for fine chemical industry and organic synthesis could be developed. The development of practical and robust iron-based catalysts for organic oxidations with high selectivity and product turnovers is likely to have a long lasting impact in the forthcoming decade. |
| Project Title: | Molecular Design and Application Studies of Photoluminescent Platinum(II) Complexes |
| Investigator(s): | Che CM, Lu W, Tong SM, Vellaisamy ALR |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 09/2007 |
| Abstract: |
| To develop new classes of Pt(II) complexes with emissive triplet metal-to-ligand charge transfer excited states in solutions at room temperature and to explore the photochemistry of water-soluble luminescent Pt(I I) complexes. To develop robust and strongly emissive Pt(II) complexes for organic optoelectronic applications. To develop nanostructured and polymeric Pt(II) materials through metal-ligand coordination and self-assembled processes driven by intermolecular metal-metal and/or ligand-ligand interactions. To investigate the binding reactions of luminescent Pt(II) complexes with biomolecular targets and to explore biological applications. |
| Project Title: | Institute of molecular technology for drug discovery and synthesis - sustained funding |
| Investigator(s): | Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Areas of Excellence Scheme |
| Start Date: | 10/2007 |
| Abstract: |
| n/a |
| Project Title: | Functional self-assembled metal coordination polymers and supramolecular systems containing extended π-conjugated organic ligands |
| Investigator(s): | Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Travel Grants for NSFC/RGC JRS |
| Start Date: | 12/2007 |
| Abstract: |
| Travel grants for NSFC/RGC JRS. |
| Project Title: | Drug |
| Investigator(s): | Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding for Strategic Research Theme |
| Start Date: | 06/2008 |
| Completion Date: | 05/2011 |
| Abstract: |
| n/a |
| Project Title: | Research & Development of New Materials for Printable Electronics |
| Investigator(s): | Che CM, Vellaisamy ALR, Kwok CC, Kui CF, Ma CW |
| Department: | Chemistry |
| Source(s) of Funding: | Platform Research Projects |
| Start Date: | 07/2008 |
| Abstract: |
| The objective of this project is to develop novel materials with practical applications in printing el ectronics, and the technological capability for production and processing of these materials. We jointly work together with Sun Yat-Sen University, Clover & Coled Display Ltd., OLED-T Ltd., and Teijin Dupont Films Japan Ltd., to boost the research and development of new materials and printing technologies. Implementation of application studies will be facilitated through partnerships with local and international display companies. |
| Project Title: | Green Chemistry. Application of Nanotechnology in the Development of Highly Efficient and Environmental Friendly Chemical Synthesis. |
| Investigator(s): | Che CM, Ho CM |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Support Programme (Tier 3) |
| Start Date: | 11/2008 |
| Completion Date: | 04/2010 |
| Abstract: |
| 1. To develop protocols for the preparation of supported metal nanoparticles with different sizes, shapes and compositions under mild conditions, and without the use of hazardous chemicals. 2. To identify and optimize the catalytic activities of supported nanometal catalysts for a) carbenoid transfer reactions, b) aerobic oxidation of amines, and c) aerobic oxidation of alcohols. 3. To conduct pilot study on gram scale synthesis of organic compounds having practical interest in fine chemicals industry. 4. To file patent(s) on the preparation and/or applications of new metal nanoparticles catalysts. |
| Project Title: | High-Performance Tandem Mass Spectrometry Facility for Functional Proteomics and Metabolomics |
| Investigator(s): | Che CM, Cheah KSE, Ma CY, Lee HC, Chan D, Tanner JA, Xu A, Sun H, Ip NY, Wong WT, Poon RTP, Wang Y, Ng KM, Chu IK, Siu AFM, Chen SF, Chye ML, Lo CSC |
| Department: | Chemistry |
| Source(s) of Funding: | UGC One-off Special Equipment Grant Scheme |
| Start Date: | 12/2008 |
| Abstract: |
| 1) to establish a high performance tandem mass spectrometry facility to support the research programs implemented under the AoE scheme, and various CERG funded projects; 2) to foster collaborative research in interdisciplinary areas involving chemistry, biological sciences and medicines, and also between the various tertiary institutions in Hong Kong; 3) to develop and attract close international collaboration with world-renowned scientists biomedical sciences; 4) to train personnel with hand-on mass spectrometry experti se who will be critical to the success of biomedical sciences in the forthcoming decade in Hong Kong and Southern China. We estimate more than 10 PhD and 5 postdoctorals will be trained using this facility annually. |
| Project Title: | Functional self-assembled metal coordination polymers and supramolecular systems containing extended π-conjugated organic ligands |
| Investigator(s): | Che CM, Lai SW |
| Department: | Chemistry |
| Source(s) of Funding: | NSFC/RGC Joint Research Scheme |
| Start Date: | 01/2009 |
| Abstract: |
| To use intermolecular pt(II)-Pt(II) and ligand-ligand interactions, and electrostatic interactions, for the preparation of functionalized nano-structured organometall ic materials, and investigation of the light-emitting, electroluminescent and charge-transport properties of these nano-structure molecular platinum(II) materials; to design, prepare and characterize self-assembled functional metal coordination polymers and to examine their materials properties and potential applications; to use transition metal ions to array extended π-conjuga ted organic molecules into one-dimensional and/or two-dimensional structures, and to examine their charge transport properties. We design, prepare and structurally characterized homoleptic M(SR) n / M(C=CAr)) n complexes containing functionalized organic R groups; to develop luminescent supramolecular system s composed of coordinative unsaturated metal ions and functionalized π-conjugated organic ligands, and to examine their potential as luminescent sensory materials. |
| Project Title: | Metal-Catalyzed Atom and Group Transfer Reactions for Selective Functionalization of Carbon-Hydrogen Bonds |
| Investigator(s): | Che CM, Ho CM, Tong SM |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2009 |
| Abstract: |
| 1) to develop sterically encumbered metalloporphyrin complexes (including chiral ones) for the functionalizat ion of saturated carbon-hydrogen bonds; 2) to perform a systematic study on the mechanism of carbene and nitrene insertion towards saturated carbon-hydrogen bonds and to examine the various factors affecting these reactions using structurally and/or spectroscopically characterized reactive metal-carbene and -nitrene complexes; 3) to develop new and inexpensive ruthenium catalyst s capable of catalyzing nitrene and carbene insertion reactions into unactivated carbon-hydrogen bonds; 4) to perform computational studies on the electronic structures of various reactive metal-carbene and nitrene derivatives of ruthenium, rhodium, iron, and gold; and to use high-resolution ESI-MS to detect the formation of some of these species in the gas phase; 5) to undertak e an exploratory study on gold-ligand multiple bonded complexes particularly those involving Au(I) and high-valent gold ions; 6) to investigate practical applications for such carbon-hydrogen functionalization reactions in organic synthesis |
| Project Title: | Reactive Metal-Ligand Multiple Bonded Complexes. From Biomimetic Reactions to Highly Efficient Chemical Synthesis |
| Investigator(s): | Che CM, Phillips DL, Chiu P, Huang JS |
| Department: | Chemistry |
| Source(s) of Funding: | Collaborative Research Fund (CRF) - Group Resear ch Project |
| Start Date: | 03/2009 |
| Abstract: |
| I) New classes of highly reactive metal-ligand multiple bonded complexes such as that of Fe(V), Fe(VI), Ru(V), Ir(V) and Ir(VII), and new metal-carbon multipl e bonded species such as bis(carbene complexes of ruthenium. II) Activation of small molecules with subsequent multi-electron transfer catalysis involving highly electrophilic metal-nitrido and imido complexes. III) Photochemistry of metal-ligand multiple bonded complexes for light-induced atom and group transfer reactions. IV) New reactions for highly efficient chemical synthe sis and modification of biomolecules. V) Highly robust catalysts for selective functionalization of alkanes. |
| Project Title: | Green Chemistry: Bioinspired Oxidation of Organic Compounds with Oxygen and/or Hydrogen Peroxide as Terminal Oxidant |
| Investigator(s): | Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 04/2009 |
| Completion Date: | 04/2010 |
| Abstract: |
| Oxidation of organic compounds plays a vital in organic synthesis, and there is an increasing demand to develop selective and efficient oxidation methods [Nature 2007, 450, 810], which are environmentally friendly. In the literature, stoichiometric oxidants such as permanganate and chromate (or its derivatives) are effective, but they pose severe safety and environmental issues in large-scale industrial processes. With emphasis on sustainable and environmentally friendly chemical processes, fine chemical and pharmaceutical industries are now looking for green oxidation technology. The use of O2 and/or H2O2 as green oxidant is highly des irable in the terms of cost and atom economy. However, organic oxidations with O2 or H2O2 are difficult to control and usually result in mixture of products. In this context, we note that there exist methods in Nature that allow for controlled selective aerobic oxidations under mild conditions by the use of metal compounds or metallo-enzymes as catalysts (e.g. Cytochrome P450 family). There have been extensive studies on the devel opment of catalytic organic oxidations involving biologically relevant metal ions as catalysts and with O2 or H2O2 as a terminal oxidant. Some significant achievements have been reported. Burgess recently published a comprehensive review article entitled “Metal-catalyzed Epoxidation of Alkenes with Hydrogen Peroxide”, in Chemical Reviews, 2003, 103, 2457. Recently, Noyori highlighted the importance of using H2O2 as an inexpensive and environmental friendly oxidant for oxidative cleavage of cyclohexene to adipic acid [Chem. Commun. 2005, 1807]. Over the past decades, my research group has extensively studied the oxidation chemistry of high-valent ruthenium- and osmium complexes and over 250 papers and reviews have been published. By virtue of the structural diversity of the auxiliary ligands, the steric and electronic properties of transition metal catalysts can be turned for stereo- and enantioselective reactions. Recently, we have developed a selective and efficient protocol based on bulky metallo porphyrin as catalyst, and air or O2 as terminal oxidant for the oxidation of 1-alkenes to aldehydes [Angew Chem. Int. Ed. 2004, 43, 4950; ibid 2008, 47, 6638]. The metal porphyrin catalyst could be recyclable and gave product yields up to 99 % and total turnover number of 1144. Notably, we have also realized two 100-gram scale practical methods for oxidation of alkenes to carboxylic acids and cis-dihydrox ylation of alkenes based on ruthenium complexes supported by 1,4,7-trimethyl-1,4,7-triazacyclononane (Me3tacn) with H2O2 as oxidant [Chem. Asian J. 2006, 1, 453; ibid 2008, 3, 70]. We have undertaken density functional theory (DFT) calculation on trans-dioxo metal complexes containing saturated amine ligands, trans-[MO2(NH3)2(NMe H2)2]2+ (M = Fe, Ru, Os), and detected of [Fe(qpy)O2]n+ (n = 1, 2) by high-resolution ESI mass spectrometry [Chem. Eur. J. 2008, 14, 5495]. In this proposal, we aim to (1) explore and develop new classes of metal catalysts for the oxidation of amines using oxygen as a terminal oxidant; (2) develop solid supported metal nanoparticles for the aerobic oxidation of amines and (3) synthesize and characterize of high-valent iron-oxo complexes for alkane oxidation. |
| Project Title: | Green Chemistry: Application of Nanotechnology in the Development of Highly Efficient and Environmental Friendly Chemical Synthesis |
| Investigator(s): | Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Fund Internship Programme |
| Start Date: | 04/2009 |
| Abstract: |
| 1. To develop protocols for the preparation of supported metal nanoparticles with different sizes, shapes and compositions under mild conditions, and without the use of hazardous chemicals. 2. To identify and optimize the catalytic activities of supported nanometal catalysts for a) carbenoid transfer reacti ons, b) aerobic oxidation of amines, and c) aerobic oxidation of alcohols. 3. To conduct pilot study on gram scale synthesis of organic compounds having practical interest in fine chemicals industry. 4. To file patent(s) on the preparation and/or applications of new metal nanoparticles catalysts. |
| Project Title: | Green Chemistry: Application of Nanotechnology in the Development of Highly Efficient and Environmental Friendly Chemical Synthesis |
| Investigator(s): | Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Fund Internship Programme |
| Start Date: | 04/2009 |
| Abstract: |
| 1. To develop protocols for the preparation of supported metal nanoparticles with different sizes, shapes and compositions under mild conditions, and without the use of hazardous chemicals. 2. To identify and optimize the catalytic activities of supported nanometal catalysts for a) carbenoid transfer reactions, b) aerobic oxidation of amines, and c) aerobic oxidation of alcohols. 3. To conduct pilot study on gram scale synthesis of organic compounds having practical interest in fine chemicals industry. 4. To file patent(s) on the preparation and/or applications of new metal nanoparticles catalysts. |
| Project Title: | Research & Development of New Materials for Printable Electronics |
| Investigator(s): | Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Fund Internship Programme (NAMI) |
| Start Date: | 07/2009 |
| Abstract: |
| The objective of this project is to develop novel materials with practical applications in printing electronic s, and the technological capability for production and processing of these materials. We jointly work together with Sun Yat-Sen University, Clover & Coled Display Ltd., OLED-T Ltd., and Teijin Dupont Films Japan Ltd., to boost the research and development of new materials and printing technologies. Implementation of application studies will be facilitated through partnerships with local and international display companies. |
| Project Title: | New Materials for Organic/polymer Base Photovoltaic Cells |
| Investigator(s): | Che CM, Kwok CC, Kui CF |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Support Programme (Tier 3) |
| Start Date: | 10/2009 |
| Abstract: |
| Photovoltaic cell is commonly made from Silicon (Si). However, the purification process creates a var iety of silane gases such as SiH4 and SiHCl3 during thermal deposition. Furthermore, only about 5% of the total Si produced during the first stage can be used as a high-purity photovoltaic material. Considering, a possible limit of the thickness of Si photovoltaic cell is 180μm. For these reasons, it is necessary to develop a new technology such as organic/polymer base photovoltaic cell in order to achieve low-price, high efficiency and light-weight devices. Organic photovoltaic cell composed of organic materials and polymer has a wide variety of advantages as below: Low Price Flexible thin film substrate can be used. Easy to process by thermal deposition and coating such as spin coating, screen printing and inkjet printing As up to now, Germany, Japan and USA all together take 80% of the worldwide solar power market. Indeed, other countries including China are also planning to replace a certain percentage of power consumption by renewable energy. Some examples are depicted in the following: Japan: Renewable Portfolio Standard (RPS) law is effective since 2003. This law requires sellers of electricity at retail to increase the use of renewable energy from new energy generation by a certain percent. Under this legal re quirement, power retailers have to ensure a certain amount of renewable energy in the energy consumption. A target of 12.2 billion kWh renewable energy productions by 2010 has been set. Germany: Germany has invested a total of 349million in the energy sector R&D in 2000, 27.2% (95 million) of which is budgeted for the renewabl e energy sector. USA: US government has invested over 24.52 trillion for energy research, development and distribution (RD&D) projects in 2000. The investments aimed at accelerating development, introduction and expansion of technology that lead to energy cost saving and pollution reduction. China: China aims to replace about 10% of total power generation with renewable energy by 2020. Photovoltaic power would be one of it. Approximately RMB$ 900 million has been budgeted for electronic automobile sector such as hybrid vehicle sector and fuel battery vehicles. Korea: Korean government is promoting a program called “Energy Vision 2030” aiming at increasing the use of renewable energy up to 9% by 2030. The main objectives are: To bring this new technology to Hong Kong/ China for application s To develop new and patentable materials for photovoltaic cells To demonstrate organic/polymer base photovoltaic cells To train postgraduate students and technical personnel for local industry |
| Project Title: | Research & Development of New Mate rials for Printable Electronics |
| Investigator(s): | Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Fund Internship Programme (NAMI) |
| Start Date: | 11/2009 |
| Abstract: |
| The objective of this project is to develop novel materials with practical applications in printing elec tronics, and the technological capability for production and processing of these materials. We jointly work together with Sun Yat-Sen University, Clover & Coled Display Ltd., OLED-T Ltd., and Teijin Dupont Films Japan Ltd., to boost the research and development of new materials and printing technologies. Implementation of applicat ion studies will be facilitated through partnerships with local and international display companies. |
| Project Title: | Phosphorescent Metal Complexes with d8 and d10 Electronic Configurations. Photochemistry, and Self-Assembled Nanostructure |
| Investigator(s): | Che CM, Lu W, Tong SM |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2010 |
| Abstract: |
| 1) to elucidate the molecular requirements whereby long-lived and emissive 3[nd(sigma*) (n+1)p(sigma)] excited states of d10 and d8 metal complexes can be generated in solutions, and to examine the photo-physica l and photochemical properties of such excited states. 2) to perform light-induced cleavage of unreactive chemical bonds such as carbon-hydrogen bonds using suitably designed d10 and d8 metal complexes as catalysts under homogeneous and heterogeneous conditions. 3) to use suitably designed donor-acceptor platinum(II) complexes for the generation of long-lived charge separated oxidized and reduced species in solutions by light excitation. 4) to develop new classes of pi-conjugat ed and sterically unencumbered ligand systems including that of aryl-acetylide, isocyanide and thioureas ligands for the construction of functionalized 1-D and 2-D nanostructures. 5) to study the materials properties of self-assembled nanostructures fabricated with d8…d8 and/or d10…d10 interactions as the driving force for the self-assembly reactions. 6) to develop the sensory applications of phosphorescent d8 and d10 metal comp lexes. |
| Project Title: | New Materials for Organic/polymer Base Photovoltaic Cells |
| Investigator(s): | Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Fund Internship Programme |
| Start Date: | 01/2010 |
| Abstract: |
| Photovoltaic cell is commonly made from Silicon (Si). However, the purification process creates a variety of silane gases such as SiH4 and SiHCl3 during thermal deposition. Furthermore, only about 5% of the total Si produced during the first stage can be used as a high-purity photovoltaic material. Considering, a possible limit of the thickness of Si photovoltaic cell is 180μm. For these reasons, it is necessary to develop a new technology such as organic/polymer base photovoltaic cell in order to achieve low-price, high efficiency and light-weight devices. Organic photovoltaic cell composed of organic materials and polymer has a wide variety of advantages as below: Low Price Flexible thin film substrate can be used. Easy to process by thermal deposition and coating such as spin coating, screen printing and inkjet printing As up to now, Germany, Japan and USA all together take 80% of the worldwide solar power market. Indeed, other countries including China are also planning to replace a certain percentage of power consumption by renewable energy. Some examples are depicted in the following: Japan: Renewable Portfolio Standard (RPS) law is effective since 2003. This law requires sellers of electricity at retail to increase the use of renewable energy from new energy generation by a certain percent. Under this legal require ment, power retailers have to ensure a certain amount of renewable energy in the energy consumption. A target of 12.2 billion kWh renewable energy productions by 2010 has been set. Germany: Germany has invested a total of 349million in the energy sector R&D in 2000, 27.2% (95 million) of which is budgeted for the renewable energy sector. USA: US government has invested over 24.52 trillion for energy research, development and distribution (RD&D) projects in 2000. The invest ments aimed at accelerating development, introduction and expansion of technology that lead to energy cost saving and pollution reduction. China: China aims to replace about 10% of total power generation with renewable energy by 2020. Photovoltaic power would be one of it. Approximately RMB$ 900 million has been budgeted for electronic automobile sector such as hybrid vehicle sector and fuel battery vehicles. Korea: Korean government is promoting a program called “Energy Vision 2030” aiming at increasing the use of renewable energy up to 9% by 2030. The main objectives are: To bring this new technology to Hong Kong/ China for applications To develop new and patentable materials for photovoltaic cells To demonstrate organic/polymer base photovoltaic cells To train postgraduate students and technical personnel for local industry |
| Project Title: | Discovery and Pre-Clinical Evaluation of Promising Metal-Based Anti-Cancer Drug Leads |
| Investigator(s): | Che CM, Sun RWY, Vanhoutte PMGR, Lin MC, Poon RTP, Wang Y, Siu AFM, Ma DL, Leung CH, Lau CK |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Support Programme (Tie r 2) |
| Start Date: | 03/2010 |
| Abstract: |
| This proposal is written based on the promising findings from the completed Tier 3 ITF- project (ITS/124/07), and the Areas of Excellence Program on Drug Discovery and Synthesis (AoE/P 10-01), and unpublished works from the laboratories of the PI and Co-Is. Previous findings from the PI/Co-Is’ laboratories are listed as below: (i) A novel drug lead (HKUAu1) has potent in vitro/in vivo anti-cancer efficacies against hepatocellular, nasopharyngeal carcinoma, and passes the acute toxicology, genotoxicity and various safety-pharmacology tests. In addition, five drug hits were identified in our pilot studies: (ii) A cyclometalated gold(III) compound (HKUAu2) with a non-toxic carbene ligand was found to exhibit promising in vitro and in vivo anti-cancer activities against hepatocellular carcinoma. (ii) Gold(III) porphyrin compounds (e.g. HKUAuP2a) have potent in vitro/in vivo anti-cancer efficacies against hepatocellular, nasopharyngeal and breast carcinoma, and pass the safety-pharmacology tests. (iii) A ruthenium drug hit (HKURu) shows anti-cancer and anti-angiogeni c properties in vitro. (iv) A gold(I) drug hit (HKUAuTU) has been found to exhibit significant in vitro anti-cancer activities with specific cytotoxicity toward cancer cells. (v) A platinum drug hit (HKUPt) has been found to be a potent topoisomerase I inhibitor, with significant in vitro anti-cancer activities. The objectives of this project include the followings: (i) complete the prerequisite in vivo and safety-pharmacological studies required for clinical evaluation of the promising metal-based drug lead HKUAu1 (or its derivative) (ii) evaluate the in vivo and in vitro anti-cancer activities of the five novel metal-based drug hits HKUAu2, HKUAuP2 a, HKUAuTU, HKUPt, HKURu identified in our pilot studies, and study their mechanism of action (iii) optimize the five novel metal-based drug hits for better anti-cancer efficacies, and complete in vitro and in vivo studies for the optimized drug leads (iv) establish the platform for drug metabolite analysis by the proposed Ultra Performance Liquid Chromatography /Quadruple-Time of Flight (UPLC/Q-TOF) system (v) create the first Database of Anti-Cancer Metal Compounds (vi) file patents application on new anti-cancer drug leads (vii) form strategic partnerships with pharmaceutical companies and research institutions (viii) establish a world-leading research center on Anti-Cancer Metal-Based Drugs in the Greater Pearl River Delta Region. |
| Project Title: | Discovery and Pre-Clinical Evaluation of Promising Metal-Based Anti-Cancer Drug Leads |
| Investigator(s): | Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Fund Internship Programme |
| Start Date: | 04/2010 |
| Abstract: |
| This proposal is written based on the promising findings from the completed Tier 3 ITF- project (ITS /124/07), and the Areas of Excellence Program on Drug Discovery and Synthesis (AoE/P 10-01), and unpublished works from the laboratories of the PI and Co-Is. Previous findings from the PI/Co-Is’ laboratories are listed as below: (i) A novel drug lead (HKUAu1) has potent in vitro/in vivo anti-cancer efficacies against hepatocellul ar, nasopharyngeal carcinoma, and passes the acute toxicology, genotoxicity and various safety-pharmacology tests. In addition, five drug hits were identified in our pilot studies: (ii) A cyclometalated gold(III) compound (HKUAu2) with a non-toxic carbene ligand was found to exhibit promising in vitro and in vivo anti-cancer activities against hepatocellular carcinoma. (ii) Gold(III) porphyrin compounds (e.g. HKUAuP2a) have potent in vitro/in vivo anti-cancer efficacies against hepatocellular, nasopharyngeal and breast carcinoma, and pass the safety-pharmacology tests. (iii) A ruthenium drug hit (HKURu) shows anti-cancer and anti-angiogenic properties in vitro. (iv) A gold(I) drug hit (HKUAuTU) has been found to exhibit significant in vitro anti-cancer activities with specific cytotoxicity toward cancer cells. (v) A platinum drug hit (HKUPt) has been found to be a potent topoisomerase I inhibitor, with significant in vitro anti-cancer activities. The objectives of this project include the followings: (i) complete the prerequisite in vivo and safety-pharmacological studies required for clinical evaluation of the promising metal-based drug lead HKUAu1 (or its derivative) (ii) evaluate the in vivo and in vitro anti-cancer activities of the five novel metal-based drug hits HKUAu2, HKUAuP2a, HKUAuTU, HKUPt, HKURu identified in our pilot studies, and study their mechanism of action (iii) optimize the five novel metal-based drug hits for better anti-can cer efficacies, and complete in vitro and in vivo studies for the optimized drug leads (iv) establish the platform for drug metabolite analysis by the proposed Ultra Performance Liquid Chromatography /Quadruple-Time of Flight (UPLC/Q-TOF) system (v) create the first Database of Anti-Cancer Metal Compounds (vi) file patents application on new anti-cancer drug leads (vii) form strategic partnerships with pharmaceutical companies and research institutions (viii) establish a world-leading research center on Anti-Cancer Metal-Based Drugs in the Greater Pearl River Delta Region. |
| Project Title: | New Materials for Organic/polymer Base Photovoltaic Cells |
| Investigator(s): | Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Fund Internship Progra mme |
| Start Date: | 06/2010 |
| Abstract: |
| Photovoltaic cell is commonly made from Silicon (Si). However, the purification process creates a variety of silane gases such as SiH4 and SiHCl3 during thermal deposition. Furthermore, only about 5% of the total Si produced during the first stage can be used as a high-purity photovoltaic material. Considering, a poss ible limit of the thickness of Si photovoltaic cell is 180μm. For these reasons, it is necessary to develop a new technology such as organic/polymer base photovoltaic cell in order to achieve low-price, high efficiency and light-weight devices. Organic photovoltaic cell composed of organic materials and polymer has a wide variety of advantages as below: Low Price Flexible thin film substrate can be used. Easy to process by thermal deposition and coating such as spin coating, screen printing and inkjet printing As up to now, Germany, Japan and USA all together take 80% of the worldwide solar power market. Indeed, other countries including China are also planning to replace a certain percentage of power consumption by renewable energy. Some examples are depicted in the following: Japan: Renewable Portfolio Standard (RPS) law is effective since 2003. This law requires sellers of electricity at retail to increase the use of renewable energy from new energy generation by a certain percent. Under this legal requirement, power retailers have to ensure a certain amount of renewable energy in the energy consumption. A target of 12.2 billion kWh renewable energy productions by 2010 has been set. Germany: Germany has invested a total of 349million in the energy sector R&D in 2000, 27.2% (95 million) of which is budgeted for the renewable energy sector. USA: US government has invested over 24.52 trillion for energy research, development and distribution (RD&D) projects in 2000. The investments aimed at accelerating development, introduction and expansion of technology that lead to energy cost savi ng and pollution reduction. China: China aims to replace about 10% of total power generation with renewable energy by 2020. Photovoltaic power would be one of it. Approximately RMB$ 900 million has been budgeted for electronic automobile sector such as hybrid vehicle sector and fuel battery vehicles. Korea: Korean government is promoting a program called “Energy Vision 2030” aiming at increasing the use of renewable energ y up to 9% by 2030. The main objectives are: To bring this new technology to Hong Kong/ China for applications To develop new and patentable materials for photovoltaic cells To demonstrate organic/polymer base photovoltaic cells To train postgraduate students and technical personnel for local industry |
| List of Research Outputs |
| Chan D.S.H. , Lee H.M. , Che C.M. , Leung C.H. and Ma D.L. , A Selective Oligonoucleotide-Based Luminescent Switch- On Probe for the Detection of Nanomolar Mercury(II) ion in Aqueous Solution., Chemical Communications . 2009, 48: 7479-7481. |
| Chan D.S.H. , Lee H.M. , Yang F. , Che C.M. , Wong C.C., Abagyan R., Leung C.H. and Ma D.L. , Structure-Based Discovery of Natural-Product-like TNF-alpha Inhibitors, Angewandte Chemie International Edition . 2010, 49: 2860-2864. |
| Chan D.S.H. , Lee H.M. , Yang F. , Che C.M. , Wong C.C.L., Abagyan R., Leung C.H. and Ma D.L. , Structure-Based Discovery of Natural-Product-like TNF- a Inhibitors, Angewandte Chemie International Edition . 2010, 49: 2860-2864. |
| Che C.M. , Kui C.F. and Kwok C.C. , Platinum (II) Isoqulinoline-Pyridine-Benzene Based Complexes, Methods For Making Same, And Organic Light-Emitting Diodes Including Such Complexes, US Reg Appln no. 12/485388 . US patent, 2009. |
| Che C.M. , (1) The Unique Phosphorescent Planar Metal Complexes. From Photocatalysis To Materials Science Application s And Medicines” And (2) Anti-cancer And Anti-viral Transition Metal Complexes”, , Invited Lectures at Visiting Hubei Scheme of Famous Scientists,20-23 May 2010, Wuhan, China. . 2010. |
| Che C.M. , Anti-Cancer and Anti-Viral Transition Metal Complexes, Invited Lectures at Visiting Hubei Scheme of Famous Scientists, Wuhan, China; May 20-23, 2010 . 2010. |
| Che C.M. , Gold Catalysed Organic Transformation Reactions, Invited Lecture at Tsing Hua University, (supported by KC Wong Education Foundation Lecturership). Beijing, China; September 24, 2009 . , 2009. |
| Che C.M. , Gold catalysed Organic Transformation Reactions, Plenary Lecture 6th National Organic Chemistry Onfe rence, Xian, China; August17-20, 2009 . 2009. |
| Che C.M. and Siu A.F.M. , Metal Complexes in Medicine with a Focus on Enzyme Inhibition , Current Opinion in Chemical Biology . 2010, 14: 255-261. |
| Che C.M. , Metal-Catalyzed Atom and Group Transfer Reactions for Practical Organic Synthesis, Invited Speaker at Frontiers In Chemistry, Singapore; 20-22 July 2009 . 2009. |
| Che C.M. and Huang J.S. , Metalloporphyrin-based oxidation systems: from biomimetic reaction to application in organic synthesis, Chemical Communications . 2009, 3996-4015. |
| Che C.M. , Metals In Medicine (medicinal Inorganic Chemistry), Anti-cancer Gold Complexes, Invited Lecture at Gordon Research Conferences: , Proctor Academy, Andover, NH, U.S.A.; June 27, 2010 to July 2, 2010, . 2010. |
| Che C.M. , Phosphorescent Square Planar Metal Complexes, Plenary Lecture at 6th Singapore International Chemical Conference (SICC 6), Singapore, December 15-18, 2009 . 2009. |
| Che C.M. , Kwok C.C. , Lai S.W. , Rausch A.F., Finkenzeller W.J., Zhu N. and Yersin H., Photophysical Properties and OLED Applications of Phosphorescent Platinum(II) Schiff Base Complexes, Chemistry--A European Journal . 2010, 16: 233-247. |
| Che C.M. , Photophysical properties, photocatalysis, and materi al science applications of phosphorescent platinum(II) complexes, Plenary Lecture at The 2nd Asian Conference on Coordination Chemistry, Nanjing, China; November 1-4, 2009 . 2009. |
| Che C.M. , Selective Activation of C-H Bonds by Atom and Group Transfer Reactions, Invited Lecture at City University of Hong Kong, Hong Kong, China; February 24, 2010 . 2010. |
| Che C.M. , Selective Alkane Activation and Aerobic Oxidations with Practical Interest, Invited Lecture at Technical Institute of Physics and Chemistry (TIPC), (supported by KC Wong Educati on Foundation Lecturership); China, September 25, 2009 . 2009. |
| Che C.M. , Self-Assembled Functional Metal Coordination Polymers and Nanostructures Directed by Metal-Metal Interactions and Metal-Ligand Bonding, Plenary Lecture at the 5th National Conference on Physical Inorganic Chemistry, Shantou, China; September 20-23, 2009 . 2009. |
| Che C.M. , Self-Assembled Multi-Functional Coordination Polymers, Invited Lecture at Molecular Engineering Symposium on Nanostructured Functional Materials for Celebrating JLU-PUV (Jilin University-Polytechnic University of Valencia) Collaboration, , April 10–11, 2010, Jilin University, Changchun, China . 2010. |
| Che C.M. , Self-assembled Metal Coordination Polymers, Invited Speaker at 6th National Conference on Coordination Chemistry,Hong Kong SAR, China; 6-9 July 2009 . 2009. |
| Che C.M. , The unique phosphorescent planar metal complexes. From photocatalysis to materials science applications and medicines, Invited Lectures at Visiting Hubei Scheme of Famous Scientists, Wuhan, China; .May 20-23, 2010 . 2010. |
| Chen R. , Cheng G. , So M.H. , Wu J., Lu Z., Che C.M. and Sun H. , Bismuth Subcarbonate Nanoparticles Fabricated By Water-in-oil Microemulsion-assisted Hydrothermal Process Exhibit Anti-helicobacter Pylori Properties, Materials Research Bulletin . 2010, 45: 654-658. |
| Chen Y. , Li K. , Lu W. , Chui S.Y. , Ma C.W. and Che C.M. , Photoresponsive Supramolecular Organometallic Nanosheets Induced by Pt II -- Pt II and C---H ... p Interactions, Angewandte Chemie International Edition . 2009, 48: 9909 –9913. |
| Chow H.M. , Sun R.W.Y. , Lam J.B.B. , Li C.K.L. , Xu A. , Abagyan R., Wang Y. and Che C.M. , A Gold(III) Porphyrin Complex with Antitumor Properties Targets the Wnt/ b -catenin Pathway, Cancer Research . 2010, 70: 329-337. |
| Chui S.Y. , Low K.H. , Roy V.A.L. and Che C.M. , Homoleptic Metal Organothiolate and Organoacetylide Coordination Polymers: Structural Determination using Powder X-ray diffraction and Their Materials Properties, AsCA'09 Beijing Joint Conference of the Asian Crys tallographic Association and Chinese Crystallographic Society . 2009. |
| Deng Q.H., Chen J., Huang J.S. , Chui S.Y. , Zhu N. , Li G.Y. and Che C.M. , Trapping Reactive Metal Carbene Complexes by a Bis-Pocket Porphyrin. X-ray Crystal Structures of Ru=CHCO2Et and trans-Ru(CHR)(CO) Species and Highly Selective Carbenoid Transfer Reactions, Chemistry - A European Journal . 2009, 15: 10707-10712. |
| Guo J.F., Yeung W.F., Lau P.H., Wang X.T., Gao S., Wong W.T. , Chui S.Y. , Che C.M. , Wong W.Y. and Lau T.C., trans- [Os III (salen)(CN) 2 ] __ : A New Paramagnetic Building Block for the Construction of Molecule-Based Magnetic Materials, Inorganic Chemistry . 2010, 49: 1607-1614. |
| Guo Y.B., Zhang Y.J., Liu H.B., Lai S.W. , Li Y.L., Li Y.J., Hu W.P., Wang S., Che C.M. and Zhu D.B., Assembled Organic/Inorganic p−n Junction Interface and Photovoltaic Cell on a Single Nanowire, The Journal of Physical Chemistry Letters . 2010, 1: 327-330. |
| Ho C.M. , Zhang J.L., Zhou C. , Chan O.Y. , Yan J. , Zhang F.Y., Huang J.S. and Che C.M. , A Water-Soluble Ruthenium Glycosylated Porphyrin Catalyst for Carbenoid Transfer Reactions in Aqueous Media with Applications in Bioconjugation Reactions, Journal of the American Chemical Society . 2010, 132: 1886-1894. |
| Ho C.M. , Yau K.W. , Lok C.N. , So M.H. and Che C.M. , Oxidative Dissolution of Silver Nanoparticles by Biologically Relevant Oxidants. A kinetic and Mechanistic Study, 17th Symposium of Chemistry Postgraduate Research in Hong Kong . 2010. |
| Ho C.M. , Yau K.W. , Lok C.N. , So M.H. and Che C.M. , Oxidative Dissolution of Silver Nanoparticles by Biologically Relevant Oxidants: A Kinetic and Mechanistic Study, Chemistry - An Asian Journal . 2010, 5: 285-293. |
| Jiang G.X., Chen J., Huang J.S. and Che C.M. , Highly Efficient Oxidation of Amines to Imines by Singlet Oxygen and Its Application in Ugi-Type Reactions, Organic Letters . 2009, 11: 4568-4571. |
| Kwok C.C. and Che C.M. , Functional Self-Assembled Zinc(II) Coordination Polymers, Macromolecules Containing Metal and Metal-Like Elements , Volume 10 . 2010, 10: 365-385. |
| Lai S.W. , Chan Q.K.W. , Han J. , Zhi Y.G. , Zhu N. and Che C.M. , Cyclometalated Pt(II) Complexes bearing Phosphinated Calix[4]arenes, The Sixth National Conference on Coordination Chemistry, The University of Hong Kong, Hong Kong, P. R. China, 6-9 July . 2009. |
| Lai S.W. and Che C.M. , Cyclometalated Pt(II) Multinuclear Assemblies and Metallomacrocyc les: Photophysical Properties and Luminescent Sensing Applications, Global COE Lectureship, Kyoto University, Japan, 3 June . 2010. |
| Lai S.W. , Chen Y. , Kwok W.M. , Zhao X.J., To W.P., Fu W. and Che C.M. , Organoplatinum(II) Complexes with Chromophore-Acceptor Dyad Studied by Ultrafast Time-Resolved Absorption Spectroscopy, Chemistry-An Asian Journal . Germany, Wiley-VCH, 2010, 5: 60-65. |
| Lai S.W. , Liu Y., Zhang D., Wang B. , Lok C.N. , Che C.M. and Selke M., Photoluminescent Properties and Singlet Oxygen Production of Cyclometalated Platinum(II) Complexes bearing Upp er-rim Phosphinated Calix[4]arenes, The Fifth International Symposium on Macrocyclic and Supramolecular Chemistry, Nara Prefecture, Japan, 6-10 June . 2010. |
| Law Y.K. , Wang M. , Ma D.L. , Al-Mousa F., Michelangeli F., Cheng S.H., Ng M., To K.F., Mok O.Y.F., Ko Y.Y. , Lam S.K. , Chen S.F. , Che C.M. , Chiu P. and Ko B.C.B., Alisol B, a novel inhibitor of the SERCA pump, induces autophagy, ER-stress and apoptosis, Molecular Cancer Therapeutics . 2010, 9: 718-730. |
| Lee H.M. , Chan D.S.H. , Yang F. , Lam H.Y., Yan S.C., Che C.M. , Ma D.L. and Leung C.H. , Identification of natural product Fonsecin B as a stabilizing ligand of c-myc G-quadruplex DNA by high-throughput virtual screening, Chemical Communications . 2010, 46: 4680-4682. |
| Lee P.Y. , Zhu Y. , Sun R.W.Y. , Hao W. , Liu X. , Che C.M. and Wong K.K.Y. , A safe and efficient lipidic nanoparticle carrier of gold porphryin for the treatment of neuroblastoma, The 3rd European Conference for Clinical Nanomedicine, Basel, Switzerland, 10-12 May 2010 . |
| Lee P.Y. , Zhu Y. , Yan J., Sun R.W.Y. , Hao W. , Liu X.L., Che C.M. and Wong K.K.Y. , The cytotoxic effects of lipidic formulated gold-porphyrin nanoparticles for the treatment of neuroblastoma, Nanotechnology, Science and Applications . 2010, 3: 23-28. |
| Li W., Xie Y. , Sun R.W.Y. , Liu Q., Young J., Yu W.Y. , Che C.M. , Tam P.K.H. and Ren Y. , Inhibition of Akt sensitises neuroblastoma cells to gold(III) porphyrin 1a, a novel antitumour drug induced apoptosis and growth inhibition, British Journal of Cancer . 2009, 101(2): 342-349. |
| Liu P. , Zhou C. , Xiang S. and Che C.M. , Highly Efficient Oxidative Carbon-carbon Coupling with SBA-15-support Iron Terpyridine Catalyst, Chemical Communications . 2010, 46: 2739-2741. |
| Liu X. , Lee P.Y. , Ho C.M. , Lui V.C.H. , Chen Y. , Che C.M. , Tam P.K.H. and Wong K.K.Y. , Silver nanoparticles mediate differential responses in keratinocytes and fibroblasts during skin wound healing, ChemMedChem . 2010, 5(3): 468-475. |
| Liu X. and Che C.M. , Highly Enantioselective Synthesis of Chiral Secondar y Amines by Gold(I)/ Chiral Brønsted Acid Catalyzed Tandem Intermolecular Hydroamination and Transfer Hydrogenation Reactions , Organic Letters . 2009, 11: 4204-4207. |
| Liu Y. , Lok C.N. , Ko C.B. , Shum Y.T. , Wong M.K. and Che C.M. , Subcellular Localization of a Fluorescent Artemisinin Derivative to Endoplasmic Reticulum, Organic Letters . 2010, 12: 1420-1423. |
| Lo K.Y. , Zhou C. , Wong M.K. and Che C.M. , Silver(I)-mediated Highly Enantioselective Synthesis of Axially Chiral Allenes Under Thermal and Microwave-assisted Conditions; The Best Poster Presentation for Organic Chemistry, The 15th Symposium on Chemistry Postgraduate Research in Hong Kong . 2010. |
| Lo K.Y. , Zhou C. , Wong M.K. and Che C.M. , Silver(I)-mediated Highly Enantioselective Synthesis of Axially Chiral Allenes Under Thermal and Microwave-assisted Conditions, Chemical Communications . 2010, 46: 213-215. |
| Low K.H. , Li C.H., Roy V.A.L., Chui S.Y. , Chan L.F. and Che C.M. , Homoleptic copper(I) phenylselenolate polymer as a single-source precursor for Cu2Se nanocrystals. Structu re, photoluminescence and application in field-effect transistor, In: David MacMillan , Chemical Science . The Royal Society of Chemistry, 2010, 1: 515-518. |
| Lu W. , Chen Y. , Roy V.A.L., Chui S.Y. and Che C.M. , Supramolecular Polymers and Chromonic Mesophases Self-Organized from Phosphorescent Cationic Organoplatinum(II) Complexes in Water , Angewandte Chemie International Edition . 2009, 48: 7621-7625. |
| Shiu H.Y.F. , Chong H.C., Leung Y.C., Wong M.K. and Che C.M. , A Highly Selective FRET-Based Fluorescent Probe for Detection of Cysteine and Homocysteine, Chemistry - A European Journal . 2010, 16: 3308-3313. |
| So M.H. , Ho C.M. , Liu Y. and Che C.M. , Aerobic oxidation of benzylic amines to imines catalyzed by graphite-supported gold nanoparticles, Eleventh tetrahedron symopsium . 2010. |
| So M.H. , Liu Y. , Ho C.M. and Che C.M. , Graphite-Supported Gold Nanoparticles as Efficient Catalyst for Aerobic Oxidation of Benzylic Amines to Imines and N-Substituted 1,2,3,4-Tetrahydroisoquinolines to Amides: Synthetic Applications and Mechanistic Study, Chemistry - An Asian Journal . 2009, 4: 1551-1561. |
| So M.H. , Ho C.M. , Chen R. and Che C.M. , Hydrothermal Synthesis of Platinum-Group-Metal Nanoparticles by Using HEPES as a Reductant and Stabilizer, Chemistry - A Asian Journal . 2010, 5: 1322-1331. |
| Sun R.W.Y. , Ng F.Y. , Wong E.L.M. , Zhang J. , Chui S.Y. , Shek L. , Lau T.C. and Che C.M. , Dual anti-angiogenic and cytotoxic properties of ruthenium(III) complexes containing pyrazolato and/or pyrazole ligands , Dalton Transactions . 2009, 10712-10716. |
| Sun R.W.Y. , Li C.K.L. , Ma D.L. , Yan J. , Lok C.N. , Leung C.H. , Zhu N. and Che C.M. , Stable anticancer gold(III)-porphyrin complexes: effects of porphyrin structure, Chemistry - A European Journal . 2010, 16: 3097-3113. |
| Tang H.W. , Lu W. , Che C.M. and Ng K.M. , Double Imaging of Latent Fingerprints by Gold Nanopar ticles-Assisted Imaging Mass Spectrometry , The 1st Asian & Oceanic Mass Spectrometry Conference, at Tsukuba International Congress Center, Tsukuba, Japan . 2010. |
| Tang H.W. , Lu W. , Che C.M. and Ng K.M. , Gold Nanoparticles and Imaging Mass Spectrometry: Double Imaging of Latent Fingerprints, Analytical Chemistry . 2010, 82: 1589–1593. |
| Tong S.M. and Che C.M. , Emissive or Nonemissive? A Theoretical Analysis of the Phosphorescence Efficiencies of Cyclometalated Platinum(II) Complexes , Chemistry -- A Europe Journal . 2009, 15: 7225-7237. |
| Tong S.M. , Law Y.C. , Kui C.F. , Zhu N. , Leung K.H., Phillips D.L. and Che C.M. , Ligand-to-Ligand Charge-Transfer Transitions of Platinum(II) Complexes with Arylacetylide Ligands with Different Chain Lengths: Spectroscopic Characterization, Effect of Molecular Conformations, and Density Functional Theory Calculations, Chemistry - A European Journal . 2010, 16: 6540-6554. |
| Tong S.M. , Kui C.F. , Chao H.Y., Zhu N. and Che C.M. , The 3 [ n d s *( n +1)p s } Emissions of Linear Silver(I) and Gold(I) Chains with Bridging Phosphine Ligands, Chemistry - A European Journal . 2009, 2009: 10777-10789. |
| Tsui W.M. , Huang J.S. , Tong S.M. , Kui C.F. , Che C.M. and Zhu N. , Quinoneimido Complexes of a Metalloporphyrin: Isolation, X-ray Crystal Structures, and DFT Calculations, Chemistry - A Asian Journal . 2010, 5: 759-763. |
| Tu S.P., Sun R.W.Y. , Lin M.C. , Cui J.T., Zou B. , Gu Q. , Kung H.F., Che C.M. and Wong B.C.Y. , Gold (III) Porphyrin Complexes Induce Apoptosis and Cell Cycle Arrest and Inhibit Tumor Growth in Colon Cancer, Cancer . 2009, 115(19): 4459-4469. |
| Wang M. , Zhou C. , Wong M.K. and Che C.M. , Ruthenium-catalyzed Alkylation of indoles with Tertiary Amines by Oxidation of a sp 3 C-H Bond and Lewis Acid Catalysis, Chemistry - A European Journal . 2010, 16: 5723-5735. |
| Wang P. , Leung C.H. , Ma D.L. , Yan S.C. and Che C.M. , Structure-Based Design of Platinum(II) Complexes as c-myc Oncogene Down-regulators and Luminescent Probes for G-quadruplex DNA, 17th Symposium of Chemistry Postgraduate Research in Hong Kong . 2010. |
| Wang P. , Leung C.H. , Ma D.L. , Yan S.C. and Che C.M. , Structure-Based Design of Platinum(II) Complexes as c- myc Oncogene Down-Regulators and Luminescent Probes for G-Quadruplex DNA, , Chemistry - A European Journal . 2010, 16: 6900-6911. |
| Wong K.K.Y. , Cheung S.O.F. , Huang L. , Niu J. , Tao C. , Ho C.M. , Che C.M. and Tam P.K.H. , Further evidence of the anti-inflammatory effects of silver nanoparticles, ChemMedChem . 2009, 4(7): 1129-1135. |
| Wu P. , Ma D.L. , Leung C.H. , Yan S.C., Zhu N. , Abagyan R. and Che C.M. , Stabilization of G-Quadruplex DNA with Platinum(II) Schiff-base Complexes: Luminescent Probe and Down Regulation of c-myc Oncogene Expression., Chemistry - A European Journal . 2009, 15: 13008-13021. |
| Xu Z. , Xiang H. , Vellaisamy A.L.R. , Chui S.Y. , Wang Y., Lai P.T. and Che C.M. , Organic field-effect transistors fabricated with N,N'-sub stituted dialkyl-1,3,8,10-tetramethylquinacridone compounds, Applied Physics Letters . 2009, 95: 123305. |
| Yan J. , Chow L.F. , Leung C.H. , Sun R.W.Y. , Ma D.L. and Che C.M. , Cyclometalated gold(III) complexes with N-heterocyclic carbene ligands as topoisomerase I poisons , Chemical Communications . Britain, Royal Chemical Society, 2010, 46: 3893 - 3895. |
| Researcher : Chen F |
| List of Research Outputs |
| Chang X.W., Zhang D.W., Chen F. , Dong Z.M. and Yang D. , A Concise Asymmetric Route to Chiral a -Aminoxy Acids, Synlett . 2009, 3159-3162. |
| Researcher : Chen G |
| Project Title: | The International Chinese Worksh op on Computational Chemistry Linear Scaling Localized-density-matrix Method for Excited State and Its Application to Nano-ma terials |
| Investigator(s): | Chen G |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 08/2000 |
| Abstract: |
| N/A |
| Project Title: | A first-principles method for calcu lating STM images of nanoscale molecular systems and its application to alkyl substituted phthalocyanines and porphyrins |
| Investigator(s): | Chen G |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 09/2002 |
| Abstract: |
| The objective of the project is to develop an efficient first-principles method to calculate the scanning tunneling microscopy (STM) images of nonoscale molecular systems and thus build an important tool in the reearch and development of nanotechnology. |
| Project Title: | Yangtze Conference on Fluids and Interfaces Optical Properties of Single-Walled Carbon Nanotubes |
| Investigator(s): | Chen G |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 10/2002 |
| Abstract: |
| N/A |
| Project Title: | First-principles simulation of dynamic responses of molecular and nanoscopic devices |
| Investigator(s): | Chen G |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2007 |
| Completion Date: | 12/2009 |
| Abstract: |
| (1) The main objective of the proposed project is to investigate the dynamic electric responses of molecular and nanoscopic devices via computer simulati on. While first-principles calculations have been carried out to study the steady currents through these electronic devices, such calculations have not been performed to simulate the transient responses of these devices. We intend to simulate in real time the evolution of electronic density distribution throughout these devices upon the application of external field. The devices of our particular interests are fullerene-based fiel d effect transistors. (2) Another major objective is to develop a highly accurate and efficient first-principles method for such real time simulations. Real time computer simulation of molecular and nanoscopic devices is a difficult challenge. Accuracy, reliability and efficiency are all required for a successful numerical calculation. To achieve this, we need to develop an entirely new first-principles method. While they have been remarkably successful, the applications of first-principles quantum mechanical methods have been limited to isolated systems where the number of electrons and energy are conserved. However, most physical, chemical and biological systems are open systems where energy as well as matter are being exchanged between the system and the surrounding. Traditionally quantum dissipation theory (QDT) has been used to study open systems. Because of the enormous computational tasks that are required, conventional numerical methods based on QDT are limited to the smal l model systems. Our proposed first-principles quantum mechanical method solves the time-evolution of reduced single-electron density matrix instead of many-body wavefunction or system density matrix, and thus requires far less computational time. The resulting formulism is expected to be rigorous. (3) Building upon the results of our numerical simulations on fullerene based electronic devices, we intend to propose new novel devices for further investigations and applications. The techniques and experiences that we acquire throug h this project can be applied to study nano-devices and other open systems. The success of our project should provide timely the new understandings for molecular- and nano-electronics. |
| Project Title: | Fluctuation-driven nanoelectromechanical systems |
| Investigator(s): | Chen G |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2008 |
| Abstract: |
| Design and simulate a model system to illustrate and confirm that thermal fluctuations can indeed be harvested to power NEMSs. Design a carbon-nanotube-based rotator that is powered by thermal fluctuation; carry out molecular dynamics simulation to examine how the thermal fluctuations are harvested and how the proposed rotator is driven. Design and simulate other NEMSs that are driven by fluctuations. |
| Project Title: | Quantum mechanical simulation of transient currents through molecular electronic devices |
| Investigator(s): | Chen G, Yam CY |
| Department: | Chemistry |
| Source(s) of Funding: | Germany/Hong Kong Joint Research Scheme |
| Start Date: | 01/2009 |
| Abstract: |
| (1) Develop an efficient quantum mechanical method for simulating the transient currents through molecular electronic devices; (2) simulate the high frequency responses of molecular based field effect transistors. |
| Project Title: | Electric properties of molecular electronic devices |
| Investigator(s): | Chen G |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2009 |
| Abstract: |
| 1) Molecular electronic devices are subjects of contemporary research. The steady state currents thro ugh these devices have been measured experimentally and calculated with first-principles quantum mechanical methods. In this work we concentrate on the transient currents through these molecular or nanoscopic electronic devices, and propose to simulate these currents using first-principles quantum mechanical methods. After having the time-dependent currents we will proceed to calculate the dynamic conductance of these devices and study systematically their electric response. Class ic electronic circuits consist of fundamental components such as resistor, capacitor, transistor and etc. By determining the dynamic conductance of these devices we propose to investigate systematically that (1) whether the molecular electronic devices can be modeled by classic electric circuits; and (2) if yes, how to model these devices in terms of classic electric components/ci rcuits, and what the equivalent electric circuits are for the molecular conductors, capacitors or transistors. We will also investigate the electric response of the nanoscopic circuits made of two or more molecular devices, and determine the relationship between the nano-circuits and their molecular components. Implication for designing next generation of electronics will be explored. 2) Second objective is to investigate the electric responses of these molecular devices. Having the time-dependent current through a molecular device under applied biased voltage, we can calculate its dynamic conductance by taking the Fourier transformation of the time-dependent current and voltage. By analyzing the frequency dependence of the conductance, we may map the electric response of a molecular device onto that of an equivalent classic electric circuit. Various carbon nanotube based conducto rs, capacitors and transistors will be the subjects of our study. 3) Having determined the equivalent electric circuits of various types of molecular devices, we will proceed to design a series of nanoscopic circuits based on a combination of these molecular devices. To overcome the computational bottleneck, we may resort to ab initio tight-binding method to simulate the electric responses of the proposed nanoelectric circuits and to investigate the relationship between the designed nano-circuits and their molecular components. Implication to the next generation of electronics will be explored. |
| Project Title: | Qantitative understanding of E. coli motility and pattern formation |
| Investigator(s): | Chen G |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 06/2009 |
| Abstract: |
| Biological patterns are normally formed from a few genetic identical cells (or even a single cell). The fundamental elements in pattern formation are spatial and temporal specific cell proliferation and movement mediated by differential gene expression and cell-cell/cell-environment communication. In this proposal, we select bacterium Eescherichi coli (E. coli) as our model system since it is the best known single cell. We aim to understand quantitaively the microscopic mechanism of individual E. coli's movement and further the pattern of its population. The proposed research will be focused on the formation of temporal and spatial patterns of E. coli. Instead of experimental approach, we will employ numerical modeling and simulation as our tools. Multiscale simulation approach including atomistic modeling will be employed to understand the mechanism of individual E. coli movement. Statistical mechanics methodolgy will be used to study the patter n formation of E. coli population. Through such investigation, we will develop theoretical tools necessary for one of our long term goals: to predict E. coli motility and pattern formation. Our specific objectives are as follows. 1. As the exact motor structures responsible for the clockwise and counter clockwise rotation of E. coli's flagella are unknown, we plan to use molec ular mechanics methods to construct and fine-tune these structures. 2. After constructing the flagella motor structures, we plan to study the respective mechanisms of flagella's clockwise and counter-clockwise rotations. We believe that some sorts of ratchet or biased Brownian motion are involved here. We will carry out detailed atomistic study to test this. 3. We will develop a multiscale method to simulate the dynamics of such complex nanoscale molecular motor, and carry out corresponding numerical simulations. 4. Based on the above studies, we will carry out numerical simulations to reproduce the observed temporal and spatial patterns of E. coli bacteria. Statistical thermodynamics methodologies will be employed. |
| Project Title: | High frequency response and equivalent circuits of all-graphene electronic devices |
| Investigator(s): | Chen G |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2010 |
| Abstract: |
| 1) Simulate quantum mechanically the electric responses of various all-graphene devices such as molecular conductor, capacitor and field-effect transistor. 2) Determine the equivalent electric circuits of the graphene-based devices. 3) Simulate all-graphene integrated circuits. |
| List of Research Outputs |
| Cheung A.S.C. , Pang H.F. , Ng Y.W. and Chen G. , Electronic Transitions of Iridium Monoboride, The 65th OSU International Symposium on Molecular Spectroscopy, Columbus, Ohio, U.S.A., June 21-25, 201 0 . WF02. |
| Kao P.Y.P. , Yang D. , Lau L.S. , Tsui H.W., Hu L. , Dai J. , Chan M.P. , Chan C.M. , Wang P. , Zheng B. , Sun J. , Huang J. , Madar J., Chen G. , Chen H. , Guan Y. and Yuen K.Y. , Identification of Influenza a Nucleoprotein as an Antiviral Target, Nature Biotechnology . 2010, 28: 600-608. |
| Liu C. , Fu X. , Chen G. , Tang L.H., Hwa T. and Huang J. , Formation of novel pattern by programming cell motility, 2010 Hong Kong Inter-University Biochemistry Postgraduat e Symposium, CUHK, Hong Kong, 15 May, . 2010. |
| Mo Y. , Zheng X., Chen G. and Yan Y.J., Transient Electronic Dynamics Of Noninteracting Open Systems Beyond Linear Response, Journal of Physics: Condensed Matter . 2009, 21: 355301-1 to 355301-11. |
| Zheng J. , Zheng X. , Yam C.Y. and Chen G. , Computer Simulation of Feynman’s Ratchet and Pawl System , Physical Review E . 2010, 81: 061104-1 to 061104-15. |
| Researcher : Chen G |
| List of Research Outputs |
| Cheung A.S.C. , Pang H.F. , Ng Y.W. and Chen G. , Electronic Transitions of Iridium Monoboride, The 65th OSU International Symposium on Molecular Spectroscopy, Columbus, Ohio, U.S.A., June 21-25, 2010 . WF02. |
| Kao P.Y.P. , Yang D. , Lau L.S. , Tsui H.W., Hu L. , Dai J. , Chan M.P. , Chan C.M. , Wang P. , Zheng B. , Sun J. , Huang J. , Madar J., Chen G. , Chen H. , Guan Y. and Yuen K.Y. , Identification of Influenza a Nucleoprotein as an Antivira l Target, Nature Biotechnology . 2010, 28: 600-608. |
| Liu C. , Fu X. , Chen G. , Tang L.H., Hwa T. and Huang J. , Formation of novel pattern by programming cell motility, 2010 Hong Kong Inter-University Biochemistry Postgradu ate Symposium, CUHK, Hong Kong, 15 May, . 2010. |
| Mo Y. , Zheng X., Chen G. and Yan Y.J., Transient Electronic Dynamics Of Noninteracting Open Systems Beyond Linear Response, Journal of Physics: Condensed Matter . 2009, 21: 355301-1 to 355301-11. |
| Zheng J. , Zheng X. , Yam C.Y. and Chen G. , Computer Simulation of Feynman’s Ratchet and Pawl System , Physical Review E . 2010, 81: 061104-1 to 061104-15. |
| Researcher : Chen H |
| List of Research Outputs |
| Chen H. , Silver Cyclyzed Enyne Cyclization Reactions (PhD Thesis) . 2009. |
| Yang D. , Yip P.K.T. , Yang M., He W. , Chen H. , Song K. and Lo K.Y. , Stereoselective Cyclization Reactions through Palladium and Silver Catalysis, The 6th Asian-European Symposium on Metal Mediated Efficient Reactions, Singapore, June 1, 2010 . 2010. |
| Researcher : Chen Q |
| List of Research Outputs |
| Chen Q. and Fung Y.S. , Coupling Continuous Micro-evaporator to Capillary Electrophoresis for Determination of Organophosphorus Pesticides in Vegetables, Abstract, 25th International Symposium on Microscale Bioseparations (MSB 2010), March 21-25, 2010, Prague, Czech Republic . 2010, P214. pp167-168. |
| Chen Q. and Fung Y.S. , Determination of Organophosphate Pesticides in Vegetables by Integrating Microextraction with Microfluidic-chip Capillary Electrophoresis, Abstract of the 9th Asia-Pacific International Symposi um on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P4-01: pp226. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Development of Molecularly Imprinted Polymer Based Piezoelectric Quartz Crystal Biosensori , Extended Abstract of 12th International Symposium on Electroanalytical Chemistry (12th ISEC), Changchun, China, August 12-15, 2009 . Page 151. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Development of Molecularly Imprinted Polymer based Piezoelectric Quartz Crystal Biosensor, Conference proceeding of the The 12th International Symposium on Electroanalytical Chemistry, August 12-15, 2009, . 2009, 151. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Nucleic Acid Based Piezoelectric Quartz Crystal Biosensor for Detection of E.coli , Conference Proceeding of The 12th International Symposium on Electroanalytical Chemistry, Changchun, China, August 12-15, 2009 . 20. |
| Researcher : Chen Q |
| List of Research Outputs |
| Chen Q. and Fung Y.S. , Coupling Continuous Micro-evaporator to Capillary Electrophores is for Determination of Organophosphorus Pesticides in Vegetables, Abstract, 25th International Symposium on Microscale Bioseparations (MSB 2010), March 21-25, 2010, Prague, Czech Republic . 2010, P214. pp167-168. |
| Chen Q. and Fung Y.S. , Determination of Organophosphate Pesticides in Vegetables by Integrating Microextraction with Microfluidic-chip Capillary Electrophoresis, Abstract of the 9th Asia-Pacific International Sympo sium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P4-01: pp226. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Development of Molecularly Imprinted Polymer Based Piezoelectric Quartz Crystal Biosensori , Extended Abstract of 12th International Symposium on Electroanalytical Chemistry (12th ISEC), Changchun, China, August 12-15, 2009 . Page 151. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Development of Molecularly Imprinted Polymer based Piezoelectric Quartz Crystal Biosensor, Conference proceeding of the The 12th International Symposium on Electroanalytical Chemistry, August 12-15, 2009, . 2009, 151. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Nucleic Acid Based Piezoelectric Quartz Crystal Biosensor for Detection of E.coli , Conference Proceeding of The 12th International Symposium on Electroanalytical Chemistry, Changchun, China, August 12-15, 2009 . 20. |
| Researcher : Chen R |
| List of Research Outputs |
| Chen R. , Cheng G. , So M.H. , Wu J., Lu Z., Che C.M. and Sun H. , Bismuth Subcarbonate Nanoparticles Fabricated By Water-in-oil Microemulsion-assisted Hydrothermal Process Exhibit Anti-helicobacter Pylori Properties, Materials Research Bulletin . 2010, 45: 654-658. |
| So M.H. , Ho C.M. , Chen R. and Che C.M. , Hydrothermal Synthesis of Platinum-Group-Metal Nanoparticles by Using HEPES as a Reductant and Stabilizer, Chemistry - A Asian Journal . 2010, 5: 1322-1331. |
| Researcher : Chen Y |
| Project Title: | 5th International Symposium on Macrocyclic & Supramolecular Chemistry Photo-Responsive Supramolecular Organometallic Nanosheets Induced by Pt-Pt and C-H-pi Interactions |
| Investigator(s): | Chen Y |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 06/2010 |
| Completion Date: | 06/2010 |
| Abstract: |
| N/A |
| List of Research Outputs |
| Chen Y. , Li K. , Lu W. , Chui S.Y. , Ma C.W. and Che C.M. , Photoresponsive Supramolecular Organometallic Nanosheets Induced by Pt II -- Pt II and C---H ... p Interactions, Angewandte Chemie International Edition . 2009, 48: 9909 –9913. |
| Lai S.W. , Chen Y. , Kwok W.M. , Zhao X.J., To W.P., Fu W. and Che C.M. , Organoplatinum(II) Complexes with Chromophore-Acceptor Dyad Studied by Ultrafast Time-Resolved Absorption Spectroscopy, Chemistry-An Asian Journal . Germany, Wiley-VCH, 2010, 5: 60-65. |
| Lu W. , Chen Y. , Roy V.A.L., Chui S.Y. and Che C.M. , Supramolecular Polymers and Chromonic Mesophases Self -Organized from Phosphorescent Cationic Organoplatinum(II) Complexes in Water , Angewandte Chemie International Edition . 2009, 48: 7621-7625. |
| Researcher : Chen Z |
| List of Research Outputs |
| Au K.M. , Wong M.C. , Chen Z. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , A Novel Class of Bis-cyclometalated Alkynylgold(III) Complexes – Synthesis, Characterization, Photophysics, Electrochemistry and the First Observation of Electro generated Chemiluminescence, The 5th International Conference on Gold Science, Technology and its Applications (organized by World Gold Council), Heidelberg, Germany, July 26–29, 2009 . |
| Au K.M. , Chen Z. , Wong M.C. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , Synthesis, Characterization, Photophysical Studies, Electrochemistry and Electrogenerated Chemiluminescence of Bis-cyclometalated Alkynylgold(III) Complexes and their Applications in Organic Light-Emitting Devices, The 42 nd International Union of Pure and Applied Chemistry (IUPAC) Congress, Glasgow, United Kingdom, August 2-7, 2009 . P701_030. |
| Au K.M. , Chen Z. , Wong M.C. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , Synthesis, Characterization, Photophysical Studies, Electrochemistry and the First Observation of Electroge nerated Chemiluminescence of Bis-cyclometalated Alkynylgold(III) Complexes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistr y) Hong Kong, P.R. China, July 6-9, 2009 . P217. |
| Researcher : Cheng CC |
| List of Research Outputs |
| Bennett M.A., Bhargava S.K., Cheng C.C. , Lam S.W.H. , Lee K.M. , Priv é r S.H., Wagler J., Willis A.C. and Yam V.W.W. , Unprecedented Near-Infrared (NIR) Emission in Diplatinum(III) (d 7 -d 7 ) Complexes at Room Temperature, Journal of the American Chemical Society . 2010, 132: 7094-7103. |
| He X. , Cheng C.C. , Zhu N. and Yam V.W.W. , Selective Ion Probe for Mg 2+ Based on Au(I) ... Au(I) Interactions in Tripodal Alkynylgold(I ) Complex With Oligoether Pendants, , Chemical Communications . 2009, 4016-4018. |
| Lee K.M. , Cheng C.C. , Zhu N. and Yam V.W.W. , Novel Air-stable Hexanuclear Gold(I) Phosphinidene Complexes Containing Redox-active Ferrocenyl Units, The 5 th International Conference on Gold Science, Techno logy and its Applications (organized by World Gold Council),Heidelberg, Germany, July 26–29, 2009 . |
| Researcher : Cheng G |
| List of Research Outputs |
| Chen R. , Cheng G. , So M.H. , Wu J., Lu Z., Che C.M. and Sun H. , Bismuth Subcarbonate Nanoparticles Fabricated By Water-in-oil Microemulsion-assisted Hydrothermal Process Exhibit Anti-helicobacter Pylori Properties, Materials Research Bulletin . 2010, 45: 654-658. |
| Researcher : Cheng KH |
| List of Research Outputs |
| Cheng K.H. , A Study on Novel Organic Semiconductor Devices: Light-emitting Diode and Thin-film Transistor (PhD Thesis) . 2009. |
| Researcher : Cheng S |
| List of Research Outputs |
| Chan G.K.Y. and Cheng S. , High Voltage Dual Electrolyte Power Sources, Licensing agreement on 14/12/2009 for the invention . 2009. |
| Chan G.K.Y. and Cheng S. , High-Voltage Dual Electrolyte Electrochemical Power Sources, The 216th Electrochemical Society Meeting, Vienna, Austria, October 4-9, 2009 . |
| Cheng S. and Chan G.K.Y. , High-Voltage Dual Electrolyte Electrochemical Power Sources, ECS Transactions . 2010, 25: 213-219. |
| Ting S.W. , Cheng S. , Tsang K.Y. , van der Laak N.K. and Chan G.K.Y. , Low Activation Energy Dehydrogenation of Aqueous Form ic acid on Platinum–ruthenium–bismuth Oxide at Near Ambient Temperature and Pressurew, Chemical Communications . 2009, 47: 7333-7335. |
| Researcher : Cheng T |
| List of Research Outputs |
| Cheng T. , Li H. , Xia W. and Sun H. , Structure and function study of SlyD in Helicobacter pylori , 21st IUBMB and 12th FAOBMB International Congress of Biochemistry and Molecular Biology, Shanghai, China, August 2-7 . 2009. |
| Researcher : Cheung ASC |
| Project Title: | Electronic transition spectrum of transition metal carbides |
| Investigator(s): | Cheung ASC |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2007 |
| Completion Date: | 12/2009 |
| Abstract: |
| To produce gas-phase transition metal (TM) carbides using the state-of-the-art laser vaporization/reaction and/or high voltage direct-current pulsed discharge followed by supersonic cooling techniques. To record and analyze the near infrared and visible spectra of TM carbides using cavity ring down spectroscopy and/ or laser induced fluorescence spectroscopy. Electronic transitions of the carbide molecules, particularly the 3d period: TiC, VC and CrC, and other diatomic TM carbides are of interest. To study and understand the electronic structure of these carbides using molecular orbital theory and compare their electronic structure across the entire first transition metal period. |
| Project Title: | Cavity ring down spectroscopy and TOF-MS investigations on the aromatization of methane hydrate over Mo catalysts under supersonic jet expansion condition |
| Investigator(s): | Cheung ASC |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2008 |
| Abstract: |
| To study catalytic reaction in a pulsed nozzle beam and detect reaction products using time-of flight mass spectrometry and cavity ring down spectroscopy. Catalytic reaction intermediates and product species can be detected in situ using these techniques; to study the transformation of methane with trace amount of water (1-3%) to aromatic hydrocarbons and hydrogen with Mo based catalysts, and to understand the mechanism of the reaction of producing aromatic compounds such as benzene, naphthalene etc, and hydrogen, and to re solve further the issue on catalytic deactivation during methane dehydroaromatization. |
| Project Title: | Hydrocarbon aromatization study over transition metal catalysts using time-of-flight mass-spectrometry |
| Investigator(s): | Cheung ASC |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 04/2008 |
| Completion Date: | 03/2010 |
| Abstract: |
| The research proposed is to investigate catalytic dehydroaromatization reaction of hydrocarbon to hydrogen and aromatic compounds such as benzene (C6H6), naphthalene (C10H8), etc using time-of-flight mass-spectrometry. Transition metal catalysts are well-known active catalysts for the dehydrogenation and aromatization of methane in the absence of oxygen. The short time scale in supersonic expansion using a pulsed nozzle would allow kinetically fast reactions to proceed and may produce new reaction products. We would like to use this approach to study the dehydroaromatization of hydrocarbons. We aim to better understand the dehydroaromatization reaction mechanism, formation of any new products and examination of catalytic deactivation and coke formation problems. The project objectives of this investigation are (i) to study catalytic reaction in a pulsed nozzle beam and detect reaction products using time-of flight mass spectrometry. Catalytic reaction intermediates and product species can be detected in situ using this technique and (ii) to study the transformation of hydrocarbon to aromatic compounds and hydrogen with transition metal based catalysts, and to understand the mechanism of the reaction of producing aromatic compounds such as benzene, naphthalene etc, and hydrogen, to resolve further the issue on catalytic deactivation during hydrocarbon dehydroaromatization. |
| Project Title: | Electronic Spectroscopy of Metal Borides |
| Investigator(s): | Cheung ASC |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2009 |
| Abstract: |
| 1) To produce gas-phase metal borides using high temperature oven system with microwave discharge and the laser vaporization/reaction for spectroscopic studies. 2) To record and analyze electronic transition spectra of metal borides using laser spectroscopic techniques. Electronic transitions of the metal boride molecules, particularly the main group 3p and transition metal early 3d period: AlB and TiB have not been observed so far. This work provides first experimental spectroscopic observation of these metal borides. 3) To determine molecular structure and understand the electronic structu re and chemical bonding involved in these metal borides using molecular orbital theory and compare their electronic structure across the entire main group and the first transition metal periods. |
| Project Title: | Resonance enhanced multi-photon ionization (REMPI) spectroscopy of metal compounds |
| Investigator(s): | Cheung ASC |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 05/2009 |
| Abstract: |
| The objective of this investigation is to study the gas-phase electronic spectrum of metal compound molecules in the visible and ultra violet (300 – 560 nm) regions using laser vaporization/reaction free jet expansion technique and the resonance enhanced multi-photon ionization time-of-flight mass spectrom etry and to determine molecular vibrational and rotational constants for electronic transitions of metal compounds. A detailed understanding of the molecular electronic structures can be derived from the study of gas-phase molecular spectra. These metal compounds are very hard, high melting, refractory molecules whose structures and stoichiometries do not conform to the ordinary concepts of valence. The production of metal compounds usually required high temperature environment. The usual hot oven or arc discharge techniques present difficulties in the vaporization of these high temperature refractory compounds. Even though thermal excitation could produce the borides in gas phase but the thermal distribution of these molecules at high temperature will greatly complicate the absorption or emission spectra obtained. In combination with the sequence congestion and extended rotational structure which invariably accompany high temperature spectra, will probably lead to spectra which are too complex to be readily analyzed [1]. Supersonic expansion is a well-known technique for cooling the internal degrees of freedom of molecules far below the normal boiling point, while maintaining the molecules in gas phase. Recently, this method has been combined with laser vaporization / reaction source to produce high boiling transition metal compounds [2]. A localized pulsed heating of the metal or metallic compounds by focused laser irradiation is technically superior to the use of a furance since it is not necessary to heat any part of the apparatus to the extreme temperature required to vaporize refractory compounds. An intense pulse beam source of gas mixtures provides chemicals for reaction with hot metal atoms. The laser vaporization / reaction technique has been proven successful in producing metallic compounds in gas phase at a very low temperature. The resonance enhanced multi-photon ionization (REMPI) time-of-flight mass (TOF-MS) has been developed into a standard technique for studying and monitoring various atomic, neutral, and ionic molecular species [3]. A REMPI experiment uses two lasers appl ied in sequence. The first pulse promotes the molecules of interest into an excited electronic state. A second probe laser is then pulsed to ionize the excited species. The resulting ions are analyzed using a time-of-flight (TOF) mass spectrometer equipped with a micro-channel plate (MCP) detector. This technique allows the absorp tion spectra of many radicals of different masses to be recorded all at once. Its greatest advantage lies in its mass-selectivity and high sensitivity, which allows one to make an unambiguous assignment of the absorption features. We are also experienced in using the laser vaporization/reaction method to produce metal compounds in gas phase for high resolution work [4]. It is prop osed here to use the laser vaporization/reaction technique to produce metal compounds with resonance enhanced multi-photon ionization (REMPI) time-of-flight mass (TOF-MS) spectroscopy to study their electronic transitions. In this study, a widely tunable and narrow linewidth laser source for REMPI spectroscopy is necessary. This is because the electronic transitions of the many metal compounds are not known, once they are produced in a jet, an extensive spectral search for the electronic transitions are inevitable. The narrow linewidth is required to obtain high resolution spectrum. References: 1. G. Hezberg, Molecular Spectra and Molecular Structu re I Van Norstrand 1950. 2. S. Maruyama, L.R. Suderson, and R.E. Smally,Rev. Sci. Instrum. 61, 3686 1990. 3. W. Demtroder, Laser Spectroscopy: Basic Concepts and Instrumentation, Springer 1995. 4. A.S.C. Cheung, Q. Ran, D..K.W. Mok, P.M. Yeung, J. Mol. Spec. 203, 96 (2000) |
| Project Title: | Laboratory astrochemistry - polycyclic aromatic hydrocarbons from photochemical reactions of acetylene on solid grain surfaces |
| Investigator(s): | Cheung ASC |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2010 |
| Abstract: |
| 1) Detailed understanding of the photochemical reactions of acetylene on solid grain surfaces exposed to ultra violet radiation, and of the formation of aromatic materials including PAHs in space. 2) Synthetic route involving solid grain surface and ultra violet radiation for the formation of more complex molecules in space. The grains may act as catalytic surface or provide a medium which brings the adsorbed species into close proximity with each other, facilitating the formation of new chemical bonds. |
| Project Title: | 65th Ohio State University International Symposium on Molecular Spectroscopy ELECTRONIC TRANSITIONS OF IRIDIUM MONOBORIDE |
| Investigator(s): | Cheung ASC |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 06/2010 |
| Completion Date: | 06/2010 |
| Abstract: |
| N/A |
| List of Research Outputs |
| Cheung A.S.C. , Cavity Ring Down Spectroscopic Studies of Transitions Metal Free Radicals and Catalytic Reactions, The 11th National Chemical Dynamics Symposium, Yi Chong, Wuhan, China, August 13-17, 2009 . I20. |
| Cheung A.S.C. , Pang H.F. , Ng Y.W. and Chen G. , Electronic Transitions of Iridium Monoboride, The 65th OSU International Symposium on Molecular Spectroscopy, Columbus, Ohio, U.S.A., June 21-25, 2010 . WF02. |
| Cheung A.S.C. , Pang H.F. , Tam W.S. and Leung W.H. , Laser Spectroscopy of Nil: New Electronic States and Hyperfine Structure, The Journal of Chemical Physics . 2009, 131: 194301-1 - 194301-7. |
| Jamieson M.J., Cheung A.S.C. and Ouerdane H., Dependence of the Scattering Length for Hydrogen Atoms on Effective Mass, The European Physical Journal D . 2010, 56: 181-188. |
| Ma T., Li L. , Leung W.H. and Cheung A.S.C. , Cavity Ring Down Laser Absorption Spectroscopy of NiI, Chinese Journal of Chemical Physics . 2009, 22: 611-614. |
| Researcher : Cheung KC |
| List of Research Outputs |
| Cheung K.C. , Yang P. , Huang Q.H., Chen Z., Chen S.J., Lin M.C. and Kung H.F., Identification of Protein Domains Required for Makorin-2- mediated Neurogenesis Inhibition in Xenopus Embryos, Biochemical and Biophysical Research Communications . 2010, 394(1): 18-23. |
| Xia H. , Ng S.M. , Jiang S.S., Cheung K.C. , Sze J. , Bian X.W., Kung H.F. and Lin M.C. , miR-200a-mediated Downregulation of ZEB2 and CTNNB1 Differentially Inhibits Nasopharyngeal Carcinoma Cell Growth, Migration and Invasion, Biochemical and Biophysical Research Communications . 2009, 391(1): 535-541. |
| Yu F. , Ng S.M. , Lum C.T. , Cheung K.C. , An X.M. and Lin M.C. , Functional Characterization of Interferon Induced Transmembrane Protein 1 (IFITM1) in Colorectal Carcinogenesis, 34th FEBS Congress: Life's Molecular Interactions; Prague, Czech Republic, 4-9, July, 2009. (P4-140, Published in the FEBS Journal) . 2009, 276 (s1): 134. |
| Zheng B. , Sze J. , Cheung K.C. , Lin M.C. and Kung H.F., Super Interferons for the Treatment of Bird Flu, Tri-Society Annual Conference 2009 of the Society for Leukocyte Biology, International Cytokine Society, & International Society for Interferon and Cytokine Research; Portugal; 17-21 October, 2009. . 2009. |
| Researcher : Cheung WH |
| List of Research Outputs |
| Ellis-Behnke R.G. , Cheung W.H. , Tay D.K.C. , Liang Y. , Lui Kau K.W.F. , Schneider G.E. and So K.F. , The control of stem cells in the brain and spinal cord by extracellular nanomatrix system, Society for Neuroscience, Chicago . 2009. |
| Researcher : Cheung WK |
| List of Research Outputs |
| Mak S.K. , Cheung W.K. , Leung Q.Y. and Chan W.K. , Conjugated Copolymers Containing Low Bandgap Rhenium(I) Complexes, Macromolecular Rapid Communications . Wiley-VCH, 2010, 31: 875-882. |
| Researcher : Chiu P |
| Project Title: | Carbonyl ylides for the generation of oxapolycycles toward the synthesis of natural products |
| Investigator(s): | Chiu P |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 07/2007 |
| Abstract: |
| To investigate and apply the cycloaddition of carbo nyl ylides generated from carbene cyclization for the synthesis of oxapolycycles toward the cyathane core structure To investigate and apply the cycloaddition of carbonyl ylides generated from carbene cyclization for the synthes is of oxapolycycles toward the grayanane core structure To examine the cleavage of C-O bonds in oxapolycyclic systems, and investigate novel approaches for selective cleavage To investigate alternative strategies to generate carbonyl ylides from non-diazo precursors and evaluate the reactivity of these intermediates |
| Project Title: | Research Output Prize (Faculty of Science) |
| Investigator(s): | Chiu P |
| Department: | Chemistry |
| Source(s) of Funding: | Research Output Prize (in Faculty) |
| Start Date: | 11/2007 |
| Abstract: |
| The Research Output Prize accords recognition to an author (or team of authors) of a single research output published or created in the preceding calendar year. Faculties are free to determine what form of research output best represents their research achievement and how it should be selected. |
| Project Title: | Development of anionic cascade reactions and other novel reactions of conjugated, accetylenic and allenic esters and thioesters. Toward the synthesis of biologically active compounds |
| Investigator(s): | Chiu P |
| Department: | Chemistry |
| Source(s) of Funding: | France/Hong Kong Joint Research Scheme - Travel Grants |
| Start Date: | 01/2008 |
| Completion Date: | 12/2009 |
| Abstract: |
| 1) To devise synthetic routes toward conjugated, acetylenic thioesters, and allenone, allenoates tethered to carbony1 functional groups; 2) to examine the reactions of these substrates with reducing agents such as copper hydrides, and with bases such as fluoride anion; 3) to apply relevant results toward the synthesis of inter esting natural and non-natural products. |
| Project Title: | Studies on Type 1 and Type 2 Intramol ecular [4+3] Cycloadditions With Epoxy Enol Silanes As Oxyallyl Cation Precursors |
| Investigator(s): | Chiu P |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 07/2008 |
| Abstract: |
| 1) To synthesize a series of Type 1 substrates tethering various dienes and epoxy silyl enol ethers.; 2) To evaluate the outcome, yield and selectivity of the Type 1 intramolecular [4+3] cycloaddition process; 3) To synthesize a series of Type 2 substrates tether ing dienes and epoxy silyl enol ethers; 4) To evaluate the outcome, yield and selectivity of the Type 2 intramolecular [4+3] cycloaddition process 5) To explore the derivatization of the cycloadducts of [4+3] cycloaddition; 6) To explore the application of Type 1 and Type 2 intramolecular [4+3] cycloaddition in the synthesis of natural products |
| Project Title: | Studies toward a second-generation synthesis of pseudolaric acid |
| Investigator(s): | Chiu P |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 01/2009 |
| Completion Date: | 06/2010 |
| Abstract: |
| To engage in exploratory studies to devise an al ternative, more concise second generation synthesis of the important anti-cancer compound, pseudolaric acid. |
| Project Title: | Development of reactions catalyzed or mediated by copper hydride |
| Investigator(s): | Chiu P |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 09/2009 |
| Abstract: |
| 1) To examine the reaction conditions, yield and scope of the copper-mediated Tishchenko reaction of aldehydes; 2) To study the reaction conditions, selectivity and efficiency of using R2SiH2 species in the copper-mediated protection of diols and triols; 3) To examine the rea ction conditions, yield and selectivity of the copper hydride mediated reductive Claisen rearrangement; 4) To conduct experiments toward the identification of alternative reductants to regenerate copper hydride; 5) To exploit the use of vinylcopper species obtained from the hydros tannation of alkynyl esters in tandem reactions; 6) To investigate new reactions mediated by copper hydrides |
| List of Research Outputs |
| Bao G.H., Wang X.L., Tang X.C., Chiu P. and Qin G.W., Sinoracutine, A Novel Skeletal Alkaloid With Cell-protective Effects From Sinomenium Acutum , Tetrahedron Letters . 2009, 50: 4375-4377. |
| Chiu P. , Chiral Sultones Via A Carbene Cyclization Cycloaddition Cascade Strategy, The International Startup Conference of Cutting-Edge Organic Chemistry in Asia (II)/ Chiba University . Japan, 2009. |
| Chiu P. , Editorial Board Member, Journal of Heterocyclic Chemistry . John Wiley & Sons, 2010. |
| Chiu P. and Lam S.K. , Ene Reactions, In: A. de Meijere, Science of Synthesis . Stuttgart, Thieme, 2009, 47: 737-754. |
| Chiu P. , Organic and Biomolecular Chemistry, Editorial Board Member . Cambridge, Royal Society of Chemistry Publishing, 2010. |
| Chu J.C.K., Wong D.K.Y. and Chiu P. , Vinylsulfonates in the Carbene Cyclization Cycloaddition Cascade Reaction, Rising Stars of Research 2009-National Undergraduate Science and Engineering Research Poster Competition . Univ British Columbia, Vancouver, Canada, 2009. |
| Lam S.K. and Chiu P. , A Novel Intermolecular [4+3] Cycloaddition of Aziridinyl Enol Silanes with Furan , The 17th Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic University, Hong Kong, April 24, 2010 . |
| Lam S.K. and Chiu P. , A Novel Intermolecular [4+3] Cycloaddition of Aziridiny l Enol Silanes with Furan , Eleventh Tetrahedron Symposium Frontiers of Organic Chemistry, Beijing, China, June 22, 2010 . PSA185. |
| Law Y.K. , Wang M. , Ma D.L. , Al-Mousa F., Michelangeli F., Cheng S.H., Ng M., To K.F., Mok O.Y.F., Ko Y.Y. , Lam S.K. , Chen S.F. , Che C.M. , Chiu P. and Ko B.C.B., Alisol B, a novel inhibitor of the SERCA pump, induces autophagy, ER-stress and apoptosis, Molecular Cancer Therapeutics . 2010, 9: 718-730. |
| Leung L.T. and Chiu P. , Poster Award, The 11th Tetrahedron Symposium . 2010. |
| Leung L.T. , Ko B.C.B. and Chiu P. , Pseudolaric Acids: Isolation, Bioactivity and Synthet ic Studies, Natural Product Reports . Cambridge, UK, Royal Society of Chemistry Publishing, 2010, 26: 1066-1083. |
| Leung L.T. and Chiu P. , Ring Opening of Oxabicyclic Compounds via the Brook Rearrangement, Poster Presentation of Eleventh Tetrahedron Symposium – Frontiers of Organic Chemistry, Elsevier and Tetra hedron Groups of Journals, Beijing, China, June 22, 2010 . |
| Li N. and Chiu P. , Copper-mediated Reductions Of Unsaturated Thioesters, The 4th International Conference on Cutting-edge Organic Chemistry in Asia . Chulaborn Res. Inst., Bangkok, Thailand, 2009. |
| Shi B., Merten S., Wong D.K.Y., Chu C.K. , Liu L.L. , Lam S.K. , J ä ger A., Wong W.T. , Chiu P. and Metz P., The Rhodium-Catalyzed Carbene Cyclization Cycloaddition Cascade Reaction of Vinylsulfonates, Advanced Synthesis and Catalysis . 2009, 351: 3128-3132. |
| Wei G. and Chiu P. , Studies Toward the Synthesis of the Pseudolaric Acids Based on RCM Reactions, The 17th Symposium on Chemistry Postgraduate Research in Hong Kong . The Hong Kong Polytechnic University, The Hong Kong Polytechnic University, 2010, O-94. |
| Researcher : Cho CKL |
| List of Research Outputs |
| Cho C.K.L. , Tse M.K. , Wong B.C.Y. and Sze K.H. , Structure Determination of the CTB by NMR Spectroscopy, Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic Univers ity, Hong Kong, April 24, 2010. . 2010, O-99. |
| Researcher : Chow LF |
| List of Research Outputs |
| Chow L.F. , Light-emitting Platinum(II) and Gold(I) complexes containing Alkynyl and Isocyanide Ligands (PhD Thesis) . 2010. |
| Yan J. , Chow L.F. , Leung C.H. , Sun R.W.Y. , Ma D.L. and Che C.M. , Cyclometalated gold(III) complexes with N-heterocyclic carbene ligands as topoisomerase I poisons , Chemical Communications . Britain, Royal Chemical Society, 2010, 46: 3893 - 3895. |
| Researcher : Chow LF |
| List of Research Outputs |
| Chow L.F. , Light-emitting Platinum(II) and Gold(I) complexes containing Alkynyl and Isocyanide Ligands (PhD Thesis) . 2010. |
| Yan J. , Chow L.F. , Leung C.H. , Sun R.W.Y. , Ma D.L. and Che C.M. , Cyclometalated gold(III) complexes with N-heterocyclic carbene ligands as topoisomerase I poisons , Chemical Communications . Britain, Royal Chemical Society, 2010, 46: 3893 - 3895. |
| Researcher : Chu CK |
| List of Research Outputs |
| Shi B., Merten S., Wong D.K.Y., Chu C.K. , Liu L.L. , Lam S.K. , J ä ger A., Wong W.T. , Chiu P. and Metz P., The Rhodium-Catalyzed Carbene Cyclization Cycloadditio n Cascade Reaction of Vinylsulfonates, Advanced Synthesis and Catalysis . 2009, 351: 3128-3132. |
| Researcher : Chu IK |
| Project Title: | 53rd ASMS Conference on Mass Spectrometr y Formation of Peptide Radical Cations in Vacuo by Electron Transfer of Cull(Amine) Peptide Complexes |
| Investigator(s): | Chu IK |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 06/2005 |
| Abstract: |
| N/A |
| Project Title: | Facile generation and characterization of cationic and anionic radical peptides: ligand eff ects and peptide structures |
| Investigator(s): | Chu IK |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 09/2006 |
| Completion Date: | 08/2009 |
| Abstract: |
| To investigate fundamental factors governing competitive reactions: a. Macrocyclic effect of auxiliary ligand; to investigate fundamental factors governing competitive reactions: b. Peptide modification to control radical peptide formation; to develop methodology for the synthesis of novel anionic radical peptides in the gas-phase; to improve the fundamental understanding of one-electron transfer and to explore the factors that govern the formation of a variety of radical peptides. |
| Project Title: | Structural Characterization and Quantification of Diabetes-Associated Glycosylation Changes in Glycodelins Using Mass Spectrometry |
| Investigator(s): | Chu IK, Lao TTH, Yeung WSB |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 09/2007 |
| Completion Date: | 08/2009 |
| Abstract: |
| (1) Structural Analysis, Sequencing, and/or Quantification of Glycodelins a)Identifying and charaterizing N-glycosylation sites in glycodelin(s); pregnancy; b)Profiling and determining compositions of N-glycans; c)N-Glycosylation changes: to explore the immunosuppressive activity of glycodelin-A derived from normal and diabetic; (2) developing and refining tandem mass spectrometry-based methodologies and technologies to enhance the mapping and characterization of N-glycopeptides. |
| Project Title: | Energetics and Dynamics of Electro n Transfer and Proton Transfer in Dissociation of MetalIII(salen)-Peptide Complexes in the Gas-Phase |
| Investigator(s): | Chu IK |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 03/2008 |
| Completion Date: | 09/2009 |
| Abstract: |
| Time- and collision energy-resolved collision-induced dissociation (SID) of ternary complexes of CoIII(sal en)+, FeIII(salen)+, and MnIII(salen)+ with several angiotensin peptide analogs will be studied using a tandem mass spectrometer. Time-resolved fragmentation efficiency curves (TFECs) will be modeled using an RRKM-based approach developed. The approach utilizes a very flexible analytical expression for the internal energy depositi on function that is capable of reproducing both single-collision and multiple-collision activation in the gas phase and excitation by collisions with a surface. The energetics and dynamics of competing dissociation pathways obtain ed from the modeling will provide important insight on the competition between proton transfer, electron transfer, loss of neutral peptide ligand, and other processes that determine gas-phase fragmentation of these model systems. Similar fragmentation behavior will be obtained for various CoIII(salen)-peptide systems of different angiotensin analogs. In contrast, dissociation pathways and relative stabilities of the complexes may change dramatically when cobalt is going to replace with trivalent iron or manganese. We will examine the electron transfer efficiency by correlating with redox properties of the metalIII(salen) complexes (Co > Fe > Mn) with diffe rences in the modes of binding between the metal-salen complex and the peptide ligand. Our preliminary RRKM modeling of time- and collision energy-resolved SID data suggests that the competition between proton transfer and electr on transfer during dissociation of CoIII(salen)-peptide complexes is mainly determined by differences in entropy effects while the energetics of these two pathways are very similar. |
| Project Title: | Formation, Isomerization and Fragmentation of Alpha-Radical Cationic Peptides |
| Investigator(s): | Chu IK |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 10/2008 |
| Abstract: |
| 1) To design, synthesize, and characterize alpha-centered radical peptides having well-defined initial radical sites. 2) To determine bond dissociation energies of radical peptides using Fourier transform ion cyclo tron resonance surface-induced dissociation (FTICR SID) experiments. |
| Project Title: | N-linked Glycoprotein Analysis Using Dual Extraction Ultra-high Performance Liquid Chromatography and Electrospray Tandem Mass Spectrome try |
| Investigator(s): | Chu IK |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 04/2009 |
| Completion Date: | 07/2010 |
| Abstract: |
| 1. Developing methodologies and technologies for on-line coupling of reversed phase (RP) and normal phase (NP) ultrahigh-pressure liquid chromatography (UPLC) for the sequential identification of peptides and glycopeptides/glycans using electrospray ionization (ESI) tandem mass spectrometry with a single sample injection event. 2. To imporve sensitivity and selectively of the analysis of peptides in the 2D-RPxNPLC-MS analysis using bottom-up analyses of tryptic-digested glycopro tein/protein mixtures. |
| Project Title: | Analytical Enhancement of Protein and Glycoprotein Identification by Means of Liquid Chromatography/Mass Spectrometry: Online Coupling of Reverse- and Normal-Phase Ultrahigh-Performance Liquid Chromatography and Dynamic Identified Protein Exclusion |
| Investigator(s): | Chu IK |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 12/2009 |
| Abstract: |
| 1) To develop a new strategy for the on-line coup ling of RP- and NP-LC for single-sample-injection LC-MS/MS analyses of complex mixtures featuring a diverse range of hydrophobicities. 2) To integrate the above platform to a generous and conventional nanoLC system for the purpose of proteome analyses of real biological samples. 3) To develop a novel instrument control system featuring interactive acquisition with IDA on-the-fly by reducing the sampling of redundant information to improve proteome coverage. |
| Project Title: | 25th International Symposium on Microscale Bioseparation (MSB 2010) An Automated Online Two-Dimensional Reverse-Phase Capillary Liquid Chromatographic System Utilizing Online Sampling Fractionation and Gradient Mixing Strategies for Shotgun Proteomics |
| Investigator(s): | Chu IK |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 03/2010 |
| Completion Date: | 03/2010 |
| Abstract: |
| N/A |
| List of Research Outputs |
| Cheng K.W. , Zeng X. , Tang Y.S., Wu J. , Liu Z.W., Sze K.H. , Chu I.K. , Chen S.F. and Wang M. , Inhibitory Mechanism of Naringenin against Carcinogenic Acrylamide Formation and Non-enzymatic Browning in Maillard Model Reactions , Chemical Research in Toxicology . 2009, 22: 1483-1489. |
| Chu I.K. , Fellowship , Fundamental Science Directorate, Pacific Northwest National Laboratory (PNNL), Department of Energy, USA . 2009. |
| Du Y. , Chu H. , Wang M. , Chu I.K. and Lo C.S.C. , Identification of flavone phytoalexins and a pathogen-induci ble flavone synthase II gene (SbFNSII) in sorghum, Journal of Experimental Botany . 2010, 61: 683-694. |
| Ge R. , Chu I.K. and Sun H. , Nuclear-based metallomics in metal-based drugs, "Advanced nuclear analytical techniques for metallomics and metalloproteomics" (Edited by C.Y. Chen, Z.F. Chai, YX Gao) . Royal Society of Chemistry, 2010, 265-298. |
| Laskin J., Yang Z.B., Ng C.M.D. and Chu I.K. , Fragmentation of α-Radical Cations of Arginine-Contai ning Peptides , Journal of the American Society for Mass Spectrometry . 2010, 21: 511-521. |
| Liu H. , Du Y. , Chu H. , Shih C.H. , Wong Y.W., Wang M. , Chu I.K. , Tao Y. and Lo C.S.C. , Molecular Dissection of the Pathogen-inducible 3-Deoxyanthocyanidin Biosynthesis Pathway in Sorghum., Plant and Cell Physiology . 2010, 51: In Press. |
| Liu H. , Lau E. , Lam P.Y. , Chu H. , Li S., Huang G., Guo P., Wang J., Jiang L., Chu I.K. , Lo C.S.C. and Tao Y., OsNOA1/RIF1 is a functional homolog of AtNOA1/RIF1: implication for a highly conserved plant cGTPase essenti al for chloroplast function., New Phytologist . 2010, 187: 83-105. |
| Ma J. , Peng X. , Cheng K.W. , Kong R., Chu I.K. , Chen S.F. and Wang M. , Effects of melamine on the Maillard Reaction between lactose and phenylalanine, Food Chemistry . 2010, 119: 1-6. |
| Ma J. , Peng X. , Cheng K.W. , Kong P.W. , Chu I.K. , Chen S.F. and Wang M. , Effects of melamine on the Maillard reaction between lactose and phenylalanine, 239th ACS National Meeting, San Francisco, CA, United States, March 21-25, AGFD-137, poster. . 2010. |
| Ng C.M.D. , Song T. , Siu S.O. , Siu C.K., Laskin J.U.L.I.A. and Chu I.K. , Formation, Isomerization, and Dissociation of alpha-Carbon-Centered and pi-Centered Glycylglycyltryptophan Radical Cations, J. Phys. Chem. B, . 2010, 114(6): 2270-2280. |
| Qi H. , Siu S.O. , Chen Y. , Han Y.F., Chu I.K. , Tong Y. , Lau A.S.Y. and Rong J. , Senkyunolide isomers H and I from Rhizoma Chuanxiong attenuate hydrogen peroxide-induced oxidative stress in human liver HepG2 cells via induction of heme oxygenase-1, 8th Meeting of Consortium for Globalization of Chinese Medicine (CGCM) . Nottingham, UK, 2009. |
| Qi H. , Siu S.O. , Chen Y. , Han Y.F., Chu I.K. , Tong Y. , Lau A.S.Y. and Rong J. , Senkyunolides reduce hydrogen peroxide-induced oxidative damage in human liver HepG2 cells via induction of heme oxygenase-1, Chemico-Biological Interactions . 2010, 183(3): 380-389. |
| Siu S.O. , Lam P.Y. , Lau E. , Yeung W.S.B., Cox D.M. and Chu I.K. , Chapter 9: N-Linked Glycoprotein Analysis Using Dual-Extraction Ultrahigh-Preformance Liquid Chromatography and Electrospray Tandem Mass Spectrometry, In: Jianjun Li , Functional Glycomics -- Methods and Products . 2010. |
| Siu S.O. , Lam P.Y. , Lau E. , Yeung W.S.B. , Cox D.M. and Chu I.K. , N-Linked Glycoprotein Analysis Using Dual-Extraction Ultrahigh-Performance Liquid Chromatography and Electr ospray Tandem Mass Spectrometry , Functional Glycomics: Methods and Protocols . 2009, 5: 133-143. |
| Wang M. , Chu I.K. and To T.K.J. , Application of epigallocatechin gallate to prevent DNA interstrand cross-links caused by reactive carbony l species, 239th ACS national Meeting, San Francisco, CA, USA, March 21-25, AGFD-84 . 2010. |
| Zeng X. , Cheng K.W. , Du Y. , Kong P.W. , Lo C.S.C. , Chu I.K. , Chen S.F. and Wang M. , Activities of hydrocolloids as inhibitors of acrylamide formation in model systems and fried potato strips, Food Chemistry . 2010, 1212: 424-428. |
| Zeng X. , Kong P.W. , Cheng K.W. , Du Y. , Tang Y.S. , Chu I.K. , Lo C.S.C. , Sze K.H. , Chen F. and Wang M. , Direct Trapping of Acrylamide as a Key Mechanism for Niacin's Inhibitory Activity in Carcinogenic Acrylamide Formation, Chemical Research in Toxicology . 2010, 23: 802-807. |
| Researcher : Chuang YP |
| List of Research Outputs |
| Li M. , Du Y. , Chuang Y.P. , Xue J. and Phillips D.L. , Water Concentration Dependent Photochemistry of Ketopro fen in Aqueous , Physical Chemistry Chemical Physics . 2010, 12: 4800-4808. |
| Researcher : Chui SY |
| Project Title: | X-ray Structural and Functional Investigations of Homoleptic Metal Organo-acetylides and thiolates |
| Investigator(s): | Chui SY, Che CM, Vellaisamy ALR |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 06/2009 |
| Completion Date: | 06/2010 |
| Abstract: |
| The chemistry of electron-rich metal-acetylides has attracted considerable attentions owing to their intriguing photoluminescent and semi-conducting properties (J. Organomet Chem 1999, 578, 3; JACS 2002, 124, 14696; Adv Mater 2006, 18, 2842). Besides, related metal thi olates constitute another interesting class of metal coordination complexes that have been studied in the views of structural diversity, biological relevance, as well as photo-con ductivity. (Polyhedron 1986, 5, 1037; Metallothioneins, 1992, 284; Angew. Chem. Int. Ed. 2008, 47, 113). In literature, most of the above-mentioned metal-acetylide or thiolate complexes formed a variety of molecular complexes with auxiliary ligands such as carbonyl (CO), phosphine (PR3), halides (X = Cl, Br and I) and other O-ligands etc, whilst related complexes containing merely one type of this ligand (either acetylide or thiolate, so-called homoleptic) are relatively less studied in literature. For the electrically neutral homoleptic metal complexes, predicting their solid-state structures is difficult owing to their versatile coordination ability of these ligands, as a result, variable metal-ligand stiochiometry would be readily assembled when these ligands bind to the multiple coordinatiion sites of the metal ions. Such high structural diversity and variability of homoleptic metal complexes prompts us to investigate their intrinsic structure-property relationship, that is a crucial step in developing them as useful functional metal-organic materials. Traditionally, single-crystal X-ray diffraction is a powerful technique to determine the 3-D solid state structure. However, when the as-synthesized complexes with increasing str uctural complexity refuse to grow big and good-quality single crystals or quickly precipitated as insoluble polycrystalline solids, these two situations will make structure determ ination using single-crystal X-ray diffraction difficult. With advances in powerful synchrotron or intensity-enhanced X-ray sources, crystallographic softwares, fast and sensitive detectors, the use of X-ray powder diffraction method recently becomes an alternative approach to solve their unknown or ab initio structures of these challenging solid samples. In this aspect, the PI ha s solved several unknown polymeric structures of insoluble metal acetylides [M(C2Ar)]n (M = Cu, Ag and Au, n = infinity) and copper(I) thiolates [Cu(SAr)]n (Ar = aryl substituents, n = infinity) using this X-ray technique, and their luminescent and semi-conductivity properties of these above-mentioned polymeric structures had been briefly studied (Chem Eur J 2005, 11, 1739 & Chem Eur J 2008, 14, 2965 and see the coverpages of the two issues). In the metal-acetylide work, we note that copper(I) t-butylacetylide formed an unusual molecular catenate complex with 20 Cu atoms, unfortunately, the structure of this complex is not stable in solution. On the contrary, owing to poor solubility in common organic solvents, the solution processibility of those insoluble metal-acetylide polymers presents a major practical problem in fabrication process of thin-film based devices such as OLED, OTFT and solar cells etc. Therefore, preparing soluble and structurally-robust metal acetylides likely provide a way to overcome this practical problem. We now propose modification of the molecular shape, size and weight of the acetylide ligands will lead to the formation of soluble and structurally-robust homoleptic metal acetylide complexes. With the use of powder X-ray diffraction, the second objective is to continue our explorations in structural diversity of homoleptic metal-thiolate complexes with other metal ions. In contrast to the 1:1 [Cu(SR)] complexes, given the same monoanionic thiolate, divalent and trivalent metal ions will be examined, in which new polymeric or oligomeric structures with different stiochiometries (1:2 and 1:3, respectively) will be generated. As we all know that Cu2S, CoS, ZnS, CdS, SnS and In2S3 are excellent photo- or semi-conductors but their chemical structures are difficult to be modified. As demonstrated in our previous work on homoleptic Cu(I) thiolate polymers, the proposed metal(II) or (III) thiolate complexes will be expected to display comparable or unusual charge-t ransporting properties. Unlike these binary metal sulfides, the proposed zinc(II), cadmium(II), tin(II), chromium(III), cobalt(III), ruthenium(III) and indium(III) thiolate complexes might form 1-D, 2-D or 3-D polymeric structures , in which their intrinsic physical and chemical properties could be tuned by their coordinated thiolate ligands. Besides, this proposal will concurrently screen the potential applications of these metal-thiolate complexes for serving as single source precursor materials so that phase-pure metal(II) or (III) sulfide nanoparticles could be conveniently prepared in high-yield. It is noteworthy that the resulting particle morphology of the as-formed metal sulfide nanoparticles is expected to be closely associated with their unique pre-organized metal-sulfur networks of these complexes. |
| Project Title: | AsCA 09 Homoleptic Metal Organothiolate and Organoacetylide Coordination Polymers: Structural Determination using Powder X-ray Diffraction and Their Materials Properties |
| Investigator(s): | Chui SY |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 10/2009 |
| Completion Date: | 10/2009 |
| Abstract: |
| N/A |
| Project Title: | Crystallization and X-ray Diffraction Studies of Homoleptic Gold(I) Thiolates and Gold-Protein Complexes relating to Rheumatoid Arthritis |
| Investigator(s): | Chui SY, Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 01/2010 |
| Abstract: |
| Homoleptic gold(I) thiolate is an unique class of metal complexes that displays interesting structur al chemistry with luminescent and medicinal properties.[1,2] The weak non-covalent Au•••Au interactions, linear coordination geometry of the Au(I) ion, as well as the covalency of the Au-S bonds, enrich its structural diversity of these complexes. These complexes are known to form ring-like and/or catenane structures in the solution and solid states[3]. However they are water-inso luble due to their non-polar peripheral aryl substituents of the thiolate ligands. Up to now, only the X-ray structure of gold(I) thiomalate had been solved by R. Bau.[4] The first objective of this project is to explore water-soluble homoleptic gold(I) thiolates complexes. Particularly, gold(I) thiopropanesulfonate (allochrysin) and gold(I) thioglucose (solgonal) are interesting because of their medicinal properties to the treatment of Rheumatoid arthritis. However their solid-state structures remains unknown for many years, probably due to its amorphous nature in the solid state . In this project, we examine the possibility in obtaining co-crystals of gold(I) thiopropanesulfonate and gold(I) thioglucose with a variety of cations and/or small molecules such as sugar, urea and thiourea. The X-ray structures of the resulting co-crystals will be determined by single-crystal X-ray diffraction method. Rheumatoid arthritis (RA) is one of human diseases, stemmed from immunological disorders.[5] This disease stimulates macrophage cells to secret high level pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) and interleukin 1 (IL-1), leading to prolonged inflammation and pains in the joints of hands, fingers and knee.[5,6] Similar to the existing disease-modifying anti-rheumatic drugs (DMARDs) such as methotrexate, water-soluble gold(I) thiolates complexes including gold(I) sodium thiomalate (myochrysine), gold(I) thiopropanesulfonate (allochrysine) and gold(I) thioglucose (solgonal) had been used to treat that disease. However the mechanism of the anti-rheumatic action is not understood.[1a] In literature, several proteins relating to human immunological system such as TNF-alpha, IL-1, 6, 15 and 18, nuclear factor kappa B (NFKB) and high mobility group box chromosom al protein (HMGB), had been targeted for inhibitory studies.[7] Notably, gold(I) sodium thiomalate had been found to inhibit the activations of HMGB and NFKB which suppress the secretion of the pro-inflammatory cytokines. There is no structural study on the gold-protein complexes of this class yet, besides other gold-protein complexes were reported. For instance, using EXAFS and Mossbauer technique, AuPEt3 fragment of auranofin is found to bind at cystein-34 residue of the human serum albumin via a ligand exchange reaction that displaces the sulfhydryl group of its thiolate ligand.[8] And the X-ray crystal structural study of gold-cyclophilin Cyp-3 complex was reported, in which the [AuPEt3]+ fragment unexpectedly bind to the N atom of the histidine-133 residue of the protein, rather than the S atom of the four thiol groups of the cysteine-40, 122, 163 and 168 residues.[9] These studies implied that both sulfur atom of cysteine and the nitrogen atom of histidine residues of the protein can be targeted for the gold(I) ion. In order to have more insights on understanding of the anti-rheumatic actions of these gold(I)-drugs, X-ray structural data relating to (1) binding sites and (2) conformational changes of the gold-protein complex is of a fundamental importance. After a quick search on protein data bank (PDB) with a keyword “gold ion”, there are 294 structu res hits but none of them relates to protein structures under the classification name of “immune system”. Also there is one structure (3HEI) found using the search keyword of “TNF and gold ion” and IL-18 had been reported to bind Mg2+ and Cl- ions (2VXT) and NFKB is found to bind Pb2+ (1HD7) and (1E9N). No X-ray structure is published for HMGB yet. Based on these findings, the second objective of this project is to use X-ray diffraction method to find out whether gold(I) thiopropa nesulfonate and gold(I) thioglucose binds some of protein targets such as TNF-alpha, IL-1, 6,15, 18, NFKB and HMGB, under normal physiological conditions. References: [1] (a) C. F. Shaw III, Chem. Rev. 1999, 99, 2589. (b) E. R. T. Tiekink, J. G. Kang, Coord. Chem. Rev. 2009, 253, 1627. [2] M. C. Grootveld, M. T. Razi, P. J. Sadler, Clinical Rheumatology, 1984, 3, 5. [3] (a) I. Schroter, J. Strahle Chem. Ber. 1991, 124, 2161. (b) M . R. Wiseman, P. A. Marsh, P. T. Bishop, B. J. Brisdon, M. F. Mahon, J. Am. Chem. Soc. 2000, 122, 12598. (c) S. S. Y. Chui, R. Chen, C. M. Che, Angew. Chem. Int. Ed. 2006, 45, 1621. [4] R. Bau, J. Am. Chem. Soc. 1998, 120, 9380. [5] Textbook of Rheumatology, W. N.Kelley, Philadelphia, Saunders, 1989. [6] (a) A. Vaz, J. Lisse, W. Rizzo, S. Albani, Expert Review of Clinical Immunology, 2009, 5, 291. (b) A. Gaffo, K. G. Saag, J. R. Curtis, American Journal of Health-System Pharmacy, 2006, 63, 2451. [7] (a) C. K. Zetterstrom, W. W. Jiang, H. Wahamaa, T. Ostberg, A. C. Aveberger, H. Schierbeck, M. T. Lotze, U. Andersson, D. S. Pisetsky, H. E. Harris, Journal of Leukocyte Biology, 2008, 83, 31. (b) E. Andreakos, S. Sacre, B. M. Foxwell, M. Feldmann, Frontiers in Bioscience, 2005, 10, 2478. (c) G. R. Burmester, Zeitschrift fur Rheumatologie, 2001, 60, 167. (d) D. M. Jue, K. I. Jeon, J. Y. Jeong, Journal of Korean Medical Science 1999, 14, 231. [8] N. A. Malik, G. Otiko, P. J. Sadler, J. Inorg. Biochem., 1980, 12, 317. [9] J. Zou, P. Taylor, J. Dornan, S. P. Robinson, M. D. Walkinshaw, P. J. Sadler, Angew. Chem. Int. Ed. 2000, 39, 2931. |
| List of Research Outputs |
| Chen Y. , Li K. , Lu W. , Chui S.Y. , Ma C.W. and Che C.M. , Photoresponsive Supramolecular Organometallic Nanoshe ets Induced by Pt II -- Pt II and C---H ... p Interactions, Angewandte Chemie International Edition . 2009, 48: 9909 –9913. |
| Chui S.Y. , Low K.H. , Roy V.A.L. and Che C.M. , Homoleptic Metal Organothiolate and Organoacetylide Coordination Polymers: Structural Determination using Powder X-ray diffraction and Their Materials Propert ies, AsCA'09 Beijing Joint Conference of the Asian Crystallographic Association and Chinese Crystallographic Society . 2009. |
| Deng Q.H., Chen J., Huang J.S. , Chui S.Y. , Zhu N. , Li G.Y. and Che C.M. , Trapping Reactive Metal Carbene Complexes by a Bis-Pock et Porphyrin. X-ray Crystal Structures of Ru=CHCO2Et and trans-Ru(CHR)(CO) Species and Highly Selective Carbenoid Transfer Reactions, Chemistry - A European Journal . 2009, 15: 10707-10712. |
| Guo J.F., Yeung W.F., Lau P.H., Wang X.T., Gao S., Wong W.T. , Chui S.Y. , Che C.M. , Wong W.Y. and Lau T.C., trans- [Os III (salen)(CN) 2 ] __ : A New Paramagnetic Building Block for the Construction of Molecule-Based Magnetic Materials, Inorganic Chemistry . 2010, 49: 1607-1614. |
| Han J., Chang X. .Y., Zhu L. .R., Pang M. .L., Meng J. .B., Chui S.Y. , Lai S.W. and Vellaisamy A.L.R. , Microwave-assisted Synthesis, Structure, and Tunable Liquid-Crystal Properties of 2,5-Diaryl-1,3,4-Thiadiazole Derivatives trough Peripheral n-Alkoxy Chains, Chemistry, An Asian Journal . 2009, 4: 1099-1107. |
| Low K.H. , Li C.H., Roy V.A.L., Chui S.Y. , Chan L.F. and Che C.M. , Homoleptic copper(I) phenylselenolate polymer as a single-source precursor for Cu2Se nanocrystals. Structure, photoluminescence and application in field-effect transistor, In: David MacMillan , Chemical Science . The Royal Society of Chemistry, 2010, 1: 515-518. |
| Lu W. , Chen Y. , Roy V.A.L., Chui S.Y. and Che C.M. , Supramolecular Polymers and Chromonic Mesophases Self- Organized from Phosphorescent Cationic Organoplatinum(II) Complexes in Water , Angewandte Chemie International Edition . 2009, 48: 7621-7625. |
| Roy V.A.L., Lo K.K.W., Chow C.F., Chui S.Y. and Lee C.S., Alignment of charge-transfer complexes for molecular devices, Journal of Materials Chemistry . 2009, 20: 434-438. |
| Sun R.W.Y. , Ng F.Y. , Wong E.L.M. , Zhang J. , Chui S.Y. , Shek L. , Lau T.C. and Che C.M. , Dual anti-angiogenic and cytotoxic properties of ruthenium( III) complexes containing pyrazolato and/or pyrazole ligands , Dalton Transactions . 2009, 10712-10716. |
| Xu Z. , Xiang H. , Vellaisamy A.L.R. , Chui S.Y. , Wang Y., Lai P.T. and Che C.M. , Organic field-effect transistors fabricated with N,N'-substituted dialkyl-1,3,8,10-tetramethylquinacridone compounds, Applied Physics Letters . 2009, 95: 123305. |
| Researcher : Chung YSC |
| List of Research Outputs |
| Yam V.W.W. , Hu Y. , Chan H.Y. and Chung Y.S.C. , Reversible pH- and Solvent-Responsive Micelle-Mediated Self-Assembly of Platinum(II) Terpyridyl-Based Metall o-Supramolecular Diblock Copolymers, Chemical Communications . 2009, 6216-6218. |
| Researcher : Cun S |
| List of Research Outputs |
| Cun S. and Sun H. , A zinc-binding site by negative selection induces me tallodrug susceptibility of an essential chaperonin, Proceedings of the National Academy of Sciences, USA . 2010, 107: 4943-4948. |
| Researcher : Dong Z |
| List of Research Outputs |
| Yang D. , Liu G.J., Hao Y. , Li W. , Dong Z. , Zhang D.W. and Zhu N. , Conformational Studies on Peptides of a -Aminoxy Acids with Functionalized Side-Chains, Chemistry - An Asian Journal . 2010, 5: 1356-1363. |
| Researcher : Du F |
| List of Research Outputs |
| Du F. and Fung Y.S. , Determination of Chlorophenols by Capillary Electrophore sis with Dual Electrode Detection for Peak Purity Assessment, Abstract, 25th International Symposium on Microscale Bioseparations (MSB 2010), March 21-25, 2010, Prague, Czech Republic . 2010, P056, pp88. |
| Du F. and Fung Y.S. , Differential Amperometric Dual Electrode Detection For Peak Purity Assessment Of Polyphenols In Red Wine After Separation By Microfluidic Chip-capillary Electrophoresis, Abstract of the 9th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P3-01: pp212. |
| Researcher : Du X |
| List of Research Outputs |
| Du X. , Wang X. , Chan D.S.B. and Sun H. , Expression, purification and characterization of the N-terminal domain of the human copper transporter (hCtr 1), 14th International Conference on Biological Inorganic Chemistry, Nagoya, Japan, July 25-30 (published in J. Biol. Inorg. Chem. 2009, 14, Suppl1, P534) . 2009, 14. |
| Wang X. , Du X. , Li H. , Chan D.S.B. and Sun H. , Effect of the N-terminal of the human high affinity copper transporter 1 (hCtr1) on cisplatin hydrolysis and uptake, 14th International Conference on Biological Inorganic Chemistry, Nagoya, Japan, July 25-30 (published in J. Biol. Inorg. Chem. 2009, 14, Suppl 1, P305) . 2009. |
| Researcher : Du Y |
| List of Research Outputs |
| Cao Q., Guan X. , George M.W., Phillips D.L. , Ma C. , Kwok W.M., Li M. , Du Y. , Sun X.Z. and Xue J. , Ultrafast Time-resolved Transient Infrared and Resonance Raman Spectroscopic Study of the Photo-deprotection and Rearrangement Reactions of p -Hydroxyphenacyl Caged Phosphates, Faraday Discuss . 2010, 145: 171-183. |
| Du Y. , Xue J. , Li M. , Guan X. , McCamant D.W. and Phillips D.L. , Unravelling the Reaction Mechanism for the Fast Photocyclisat ion of 2-Benzoylpyridine in Aqueous Solvent by Time-Resolved Spectroscopy and Density Functional Theory Calculations, Chemistry - A European Journal . 2010, 16: 6967-6972. |
| Li M. , Du Y. , Chuang Y.P. , Xue J. and Phillips D.L. , Water Concentration Dependent Photochemistry of Ketoprofen in Aqueous , Physical Chemistry Chemical Physics . 2010, 12: 4800-4808. |
| Ma C. , Kwok W.M., An H. , Du Y. , Toy P.H. and Phillips D.L. , Femtosecond Transient Absorption and Nanosecond Time-resolved Resonance Raman Study of Photo-deprotection Reaction s of Benzoin Caged Phototriggers , Femtochemistry IX: Femtochemistry, Femtobiology, and Femtophysics -- Frontries in Ultrafast Science and Technology, Beijing, China, August 8-13, 2009 . P-43: 111. |
| Ma C. , Kwok W.M. , Chan W.S. , Du Y. , Zuo P. , Kan T.W. , Toy P.H. and Phillips D.L. , Time-Resolved Spectroscopy Studies of the Photodeprotection Reactions of p -Hydroxyphenacyl Ester Phototrigger Compounds, Current Science . 2009, 97: 202-209. |
| Researcher : Duan G |
| List of Research Outputs |
| Duan G. , Synthesis, Photophysics and Photochromic Studies of Dithienylethene-Containing Imidazolium Salts and N-Heterocyclic Carbene-Ruthenium(II) Complexes . 2010. |
| Researcher : Fu W |
| List of Research Outputs |
| Lai S.W. , Chen Y. , Kwok W.M. , Zhao X.J., To W.P., Fu W. and Che C.M. , Organoplatinum(II) Complexes with Chromophore-Acceptor Dyad Studied by Ultrafast Time-Resolved Absorption Spectroscopy, Chemistry-An Asian Journal . Germany, Wiley-VCH, 2010, 5: 60-65. |
| Researcher : Fu Y |
| List of Research Outputs |
| Ma C. , Kwok W.M., An H. , Guan X. , Fu Y. , Toy P.H. and Phillips D.L. , A Time-Resolved Spectroscopic Study of the Bichromophori c Phototrigger 3', 5'-Dimethoxybenzoin Diethyl Phosphate: Interaction Between the Two Chromophores Determines the Reaction Pathway, Chemistry - A European Journal . 2010, 16: 5102-5118. |
| Ma C. , Kwok W.M., An H. , Fu Y. , Toy P.H. and Phillips D.L. , Time-resolved Spectroscopy Studies of the Bichromophoric Phototrigger 3', 5'-dimethoxybenzoin Diethyl Phospate, The 2nd Asian Spectroscopy Conference, Seoul, Korea, November 30 - December 3, 2009 (Poster Presentation) . 2009. |
| Researcher : Fung YS |
| Project Title: | Biomedical Nanoparticle Analysis System Based On Hyphenating Gas-Phase Electrophoretic Mobility Molecular Sizer With Nanometer Aerosol Sampler And Elemental Analyzers For Morphological And Chemical Analysis Of Mitochondria From Mouse Oocyte |
| Investigator(s): | Fung YS, Lin BC, O WS, Yeung WSB |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 09/2007 |
| Abstract: |
| An electrospray interface to couple with capillary electrophoresis for sample introduction and for direct flow transfer of oocyte isolated from mouse follicle and captured in a glass capillary to the electrospray capillary for isolation of mitochondria, production of dry singly charge aerosol with a single mitochondria for Gas-Phase Electrophoretic Mobility Molecular Sizer (GEMMS) separation. Analytical performance for off-line analysis using Electron Microscope, Inductively Coupled Plasma-Atomic Emission Spectrometry/Mass Spectrometry and Flame Photometric Detection for calcium and other metal determination in mitochondria collected by Nanometer Aerosol Sampler with different morphology and shape. An interface for online coupling of GEMMS with Flame Photometric Detection and Condensation Particle Counter. An interface for online coupling of GEMMS with Inductively Coupled Plasma-Atomic Emission Spectrometry and Mass Spectrometry Detection. Optimized working conditions and analytical performance of the Biomedical Nanoparticle Analysis System developed for sizing, collection and chemical characterization of mitochondria in mouse oocyte for calcium and other metallic ions. Study of the effect of mitochondrial change on fertility decline in aged mouse as an animal model and the significance of results for age-related decline of fertility in women. |
| Project Title: | Microfluidic Devices Based on Molecular Diffusion and Piezoelectric Quartz Crystal Sensor for Environmental and Biomedical Applications |
| Investigator(s): | Fung YS, Yeung WSB, O WS, Wong KY |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 04/2008 |
| Completion Date: | 03/2010 |
| Abstract: |
| The proposal aims to combines the two research lines undertaking in my research group over the previous 20 years. The first line of research is the development of methodology based on capillary electrophoresis with focus on environmental and biomedical application such as determination of free bilirubin in cord blood and pesticide contamination of environmental water and vegetables [1-3]. In collaboration with the Research Centre for Development and Reproduction and supported by a recently awarded RGC grant (RGC7023/07P), the research has concentrated on cell-based separation for 2-D protein separation and mitochrondria determination in cells and embryo, making use of the recent advancement in microfluidics technology and its coupling to capillary electrophoresis [4,5]. The second research line supported by another RGC grant (RGC7043/03P) is focused on the development of piezoelectric quartz crystal (PQC) sensor for field application such as assay of low E. Coli count for environmental water and onsite determination of pesticide contamination of vegetables [6,7]. Combining both lines of research enables the advancement of the current research towards field analysis using portable quartz sensor and to remove sample matrix interferences, in particular for whole blood and vegetable samples with high organic contents, by pretreatment procedures based on various microfluidics technologies. This is made possible by the expertise, equipment and facilities built recently in our research group for the fabrication of microchip-capillary electrophoresis by laser ablation with micro-len focusing using the microelectromechanical system (MEMS) constructed. The application of MEMS in the fabrication of electronic tongue based on PQC sensor leads to a highly success development of a min iature PQC 8-sensor array for quality assessment of taste for the food and drink industry under the funding of a research grant (ITS108/06) from the Innovation and Technology Fund awarded in September 2006. An overwhelming response has received from the media during the recent public exhibition of the electronic tongue developed at the Innovation Expo 2007 held at the Hong Kong Ho ng Kong Convention and Exhibition Centre in September this year. With a goal is to produce a practical device for environmental and biomedical application, the size of the device needs to be further reduced to a microfluidic chip with micron size channels to enable direct online sample pretreatment coupled to PQC detection. This is needed for analysis of samples with very limited amount such as analysis of blood samples from neonates and characterization of mitochrondria extracted from a single cell, as well as analysis of E.Coli in drinking water requiring detecting less than one cell in 100 mL solution. Making use of the fact that microfluidic channels with dimensions much less than 1 mm, a laminar flow could be obtained for fluids flowing at low velocities with viscosities similar to or higher than that of water, microfluidic chip could be fabricated with transfer of analytes based on molecular diffusion between adjacent flows [8,9]. A T-junction could be fabricated in mic rofluidic chip with parallel flow of two streams, the whole blood as sample stream next to the receptor stream which direct the analytes extracted to PQC for detection. No mixing will occur except molecular diffusion for low molecular weight analytes extracted from the blood stream. Thus, sample pretreatment such as cleanup and preconcentration can be carried out on-chip for analy tes prior to their determination by PQC sensor in the receptor stream. By direct online coupling of a suitable microfluidic sample pretreatment procedure with the sensitive and portable PQC for detection, an onsite analytical unit can be constructed for bedside monitoring of molecules with biomedical significance and also offering a capability for quick response to environmental contamination of toxic chemicals and pathogenic bacteria. This is a general approach with a wide application. Our initial plan will be focused on developing such devices in support of existing projects in collaboration with the Department of Paediatrics & Adolescent Medicine, Department of Microbiology, Department of Obstetrics & Gynaecology and Department of Anatomy. A summary of the objectives are given below: 1) Fabricate various microfluidic devices based on molecular diffusion such as T-sensor and V-channel design and testing their performance in attaining laminar flow and molecular diffusion. 2) Investigate the applicability of the selected microfluidic channel designs for online cleanup of bacteria and blood samples prior to detection. 3) Direct coupling of the microfluidic devices developed to the piezoelectric quartz crystal sensor for detection of bilirubin, pesticide and nucleic acid fragments. 4) Investigate methods and procedures for preconcentration of analytes prior to detection by the piezoelectric quartz crystal sensor. 5) Assessment of the overall analytical performance of the microfluidics/PQC setup developed to given applications. References 1) C.Y. Yeung, Y.S. Fung and D.X. Sun, “Capillary Electrophoresis for the determination of albumin binding capacity and free bilirubin in jaundiced neonates”, Sem. Perinatol. 2001, 25(20), 50-54. 2) Z.P. Yang, S.H. Si and Y.S. Fung, “Bilirubin adsorption on nanocrystalline tita nia films”, Thin Solid Films 2007, 515, 3344-3351. 3) Y.S. Fung and J.L.L. Mak, “Determination of pesticides in drinking water by micellar electrokinetic capillary chromatography”, Electrophoresis, 2001, 22(11), 2260-2269. 4) R. G. Wu, Y. S. Fung and W. S. B. Yeung, “Microfluidic Chip-capillary Electrophoresis for 2-D Separation of Proteins” to be presented at Asia-Pacific Capillary Electrophoresis and Related Microscale Techniques (APCE2007), Singapore, Dec. 16-19, 2007. 5) W.F. Zhao, W.S. O, Y.S. Fung, “Quantitation of mitochondria separated by capillary electrophoresis” to be presented at Asia-P acific Capillary Electrophoresis and Related Microscale Techniques (APCE2007), Singapore, Dec. 16-19, 2007. 6) H. Sun and Y.S. Fung, "Piezoelectric quartz crystal sensor for rapid analysis of pirimicarb residues using molecular ly imprinted polymers as recognition elements", Anal. Chim.Acta, 2006, 576, 67-76. 7) H. Sun, Y. Y. Zhang and Y.S. Fung, “Flow analysis coupled with PQC/DNA biosensor for assay of E.Coli based on detecting DNA products from PCR amplification”, Biosens. Bioelectron. 2006, 22, 506-512. 8) B.H. Weigi, J. Kriebel, K.J. Mayes, T. Bui, P. Yager, Mikrochim. Acta 1999, 131, 75-83. 9) M.S. Hasenbank, E. Fu, J.B. Nelson, D.T. Schwartz, P. Yager, Lab-on-a-Chip 2007, 7, 441-447. |
| Project Title: | Chemiluminescence Detection Integrated With Microchip Capillary Electrophoresis For The Determination Of Unbound Serum Bilirubin In Newborn Babies At Queen Mary Hospital, Hong Kong |
| Investigator(s): | Fung YS, Lin BC, Wong KY |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 09/2008 |
| Abstract: |
| 1) To design and fabricate a new microfluidic chip capable of interfacing with the CE/FA chip to direct the unbound bilirubin separated by CE/FA through the microfluidic channels to react with the chemiluminescence (CL) reagents for light emission at a designated position. 2) To develop a CL detection unit using a highly sensitiv e photomultiplier with adjustable control by lens and slit to collect CL light emitted from a suitable length of the CL coil to achieve high sensitivity with adequate resolution of unbound bilirubin. 3) To test and evaluate the various microchip designs for passive mixing in microfluidic channels to achieve the highest CL light emitted due to the reaction of unbound bilirubin sep arated by CE-FA with CL reagents generated directly on microchip. 4) To optimize operational parameters for the CE-FA/CL system developed, establish its scope of application to clinical samples received from Queen Mary Hospital and assess its relative merits in the determination of unbound bilirubin and the residual binding capacity of albumin for unbound bilirubin. 5) To conduct a preliminary clinical survey using the CE-FA/CL system developed to establish the methodology developed under clinical environment at Queen Mary Hospital and to assess the effectiveness of intervention measures taken in the management of unbound bilirubin for newborn infants. |
| Project Title: | Development of Technology and Application of High Power/High Energy Lithium Ion Storage Battery |
| Investigator(s): | Fung YS, Zhu D |
| Department: | Chemistry |
| Source(s) of Funding: | Guangdong-Hong Kong Technology Cooperation Funding Scheme |
| Start Date: | 03/2009 |
| Abstract: |
| The project aims at the development and optimization of new Ionic Liquid (IL) systems for high energy/high drain lithium ion battery. |
| Project Title: | In-Channel Microelectrode Detection For Microfluidic Chip-Capillary Electrophoresis For Onsite Determination of Biomedical Significant Molecules |
| Investigator(s): | Fung YS, Zhu D, Sun H |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 03/2009 |
| Abstract: |
| After the completion of the human genome project , a very rapid development has occurred in proteome research for studying DNA-protein interaction in order to understand the path for the progress of diseases and the occurrence of given medical conditions [1, 2]. During the cours e of study, numerous protein drugs, biomarkers, tumor markers and functional molecules of biomedical significance have been found which can provide useful information for early diagnosis and design of procedure for medical treatment [3-6]. In order to utilize the full benefits from the recent discovery, portable devices capable of bedside monitoring of important molecules of biome dical significance are needed to be developed to deliver quick results for their monitoring in bio-fluids for biomedical analysis and clinical diagnosis. The increasing public concern about food safety and organic environmental pollutants also give rise to the need for the development of portable devices to deliver quick results for the monitoring of toxic pollutants in the environment and harmful substances in food and water. In order to meet the need for development of portable analytical devices capable of determining important analytes in complicated sample matrix, we have conducted research on microfluidic devices over the years. In the present proposal, we plan to extend its scope of application through the development of portable detection devices to enable its field application for clinical and environmental analysis The objectives of the research to develop such devices are: 1) To develop a portable, economic and sensitive mode of detection for microfluidic chip to enable its field application for clinical and environmental analysis 2) To fabricate Microfluidic Chip-Capillary Electrophores is devices incorporating an Ultramicroelectrode for In-Channel detection and assess their analytical performance 3) To investigate the applicability of internal electrolyte-free Selective Potentiometric Electrode for In-Channel detection of biomedical significant molecules 4) To fabricate and study Microfluidic Chip-Capillary Electrophoresis devices incorporating Serial Dual Electrode Detection for In-Channel Detection of Proteins and assess their analytical application in biofluids 5) To assess the applicability of Microfluidic Chip-Capillary Electro phoresis devices incorporating In-Channel Selective Electrode/Dual Electrode Detection for targeted biomedical significant molecules The recent rapid advance in the development of microfluidic devices provides a promising analytical technology capable of clinical bedside monitoring of biomedical significant molecules. The current major issue for their implementation in environmental and clinical analysis is the lack of a portable, economic and sensitive mode of detection. Electrochemical detection provides a sensitive and economic method. However, the method is limited only to those molecules with electrochemically active functional group. The use of selective potentiometric detection will broaden its application to small charged or non-charged molecule s. The use of dual electrode detection with electrochemical generation of iodine prior to the detection of the residual iodine after their chemical reaction with proteins which interact strongly with iodine. The indirect mode of detection enables a more general detection scheme for large molecules of biomedical significance. The technical problems to be tackled in the development of electrochemical detection mode for microfluidic devices are the dead volume of the detector which can significantly affecting the separation efficiency. This demands high degree of miniaturization of detectors placed at strategic position in the detection system. The recent advance in the development of internal electroyte-f ree selective electrode enable the use of micro-fiber electrode for in-channel detection for microfluidic devices. Our capability based on computer-aided design for fabrication of microfluidic devices using laser ablation allows us to design and fabricate microfluidic devices capa ble to incorporate two microelectrodes at suitable distance in microfludic devices for dual electrode detection of proteins and other biomedical significant molecules using procedures which we have developed previously using dual electrode mode of detection for biomedical significant molecules in Flow Injection Analysis and after HPLC separation [7-10]. Details on the research plan and methodology to be developed will be given in section VII. References 1) T. Shitama, H. Hayashi, S. Noge, E. Uchio, K. Oshima, H. Haniu, N. Takemori, N. Komo ri and H. Matsumoto, “Proteome profiling of vitreoretinal diseases by cluster analysis”, Proteomics Clin. Application., 2008, 2(9),1265-1280. 2) Z.Y. Xun , T.C. Kaufman and D.E. Clemmer, “Proteome response to the pan neutral expression of human wide-type alpha-synuclein : A Drosophia model of Parkinson’s disease”, J. Proteomics Res., 2008, 7(9), 3911-3921. 3) J.M. Gonzalez-Buitrago, L. Ferreira and M.D. Muniz,”Clinical Proteomics and new bimarkers in biological fluids”, Med. Clinica, 2008, 131 (11), 426-434. 4) T. Niwa, “Biomarker discovery for kidney diseases by mass spectrometry”, J. Chromatogr. B- Anal. Tech. Biomed. & Life Sci., 2008, 870 (2),148-153. 5) J. Wu , Z.F. Fu, F.Yan and H. Ju,”Biomedical and clinical applicat ions of immunoassays and immunosensors for tumor markers”, Trac-Trends Anal. Chem.,2007, 26(7), 679-688. 6) S.T. Stinghen, J.F. Moura, P. Zancanella, G.A. Rodrigues, M.A. Planovski, E. Lalli, D.L. Arnold, J.C. Minozzo, L.G. Callefe, P.C. Ribeiro and B.C. Figueredo, “Specific immuoassays for placental alkaline phophatase as a tumor marker”, J. Biomed. Biotech., 2006, Article Num ber: 56087. pp 1-8. 7) Y.S. Fung and S. Y. Mo, " Application of Dual Pulse Voltammetry for Simultaneous Determination of Glucose and Fructose ", Electroanal., 1995, 7(2), 160 165. 8) Y.S. Fung and S.Y. Mo, " Determination of Amino Acids and proteins by Dual Electrode Detector in a Flow System", Anal. Chem., 1995, 67 (6), 1121 1124. 9) Y.S. Fung and S. Y. Mo, “ Study of pulse generation technique for serial dual electrode detection of amino acids and proteins in flow injection analysis”, Anal. Sci. Tech., 1995, 8(4), 575-582. 10) Y.S. Fung and S.Y. Mo, “Determination of Ethanol in Beer by Flow Injection Dual-pulse Staircase Voltammetric Detection “, Analyst, 1996, 121, 369-372. |
| Project Title: | Development of Technology and Application of High Power/High Energy Lithium Ion Storage Battery |
| Investigator(s): | Fung YS |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Fund Internship Programme |
| Start Date: | 03/2009 |
| Abstract: |
| The project aims at the development and optimization of new Ionic Liquid (IL) systems for high energy/high drain lithium ion battery. |
| Project Title: | Development of Technology and Ap plication of High Power/High Energy Lithium Ion Storage Battery |
| Investigator(s): | Fung YS |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Fund Internship Programme |
| Start Date: | 03/2009 |
| Abstract: |
| The project aims at the development and optimization of new Ionic Liquid (IL) systems for high energy/hig h drain lithium ion battery. |
| Project Title: | Fabrication and Development of Bedside Monitoring Device for Clinical Management of Free Bilirubin in Serum for New Born Babies Under Critical Conditions Based on Microfluidic Chip-Capillary Electrophor esis |
| Investigator(s): | Fung YS, Wong KY |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Applied Research |
| Start Date: | 06/2009 |
| Abstract: |
| The current practice for treating neonates for jaundice to reduce the risk of neurologic abnormalities such as kernicterus, a serious brain injury that can affect the future IQ development of newborn infants, depends on the measurement of elevated levels of total serum bilirubin to provide an important indicator fo r intervention [1, 2]. However, unbound unconjugated bilirubin present in serum of neonates instead of total serum bilirubin has been well established to provide a more reliable indicator to predict the toxicity of hyperbilirubinemia [3-5]. It has been proposed to use bilirubin index based on the exposure duration and the level of free or unbound serum bilirubin as a standard for intervention [4]. To provide an improved health care management system against the risk of kernicteru s, the levels of unbound bilirubin should be monitored regularly for newborns with a high risk of kernicterus such as serum with a low capacity to bind bilirubin and the occurrence of hypoxia, acidosis, acute or ongoing hemolysis due to G6PO deficiency and other medical conditions that can increase the levels of unbound bilirubin and/or to enhance its flux through the blood-brain barrier, causing brain injury [4, 6-9]. Although the use of unbound bilirubin provides a better indicator, it is difficult to measure due to its extremely low levels present in serum, as the majority of bilirubin are albumin-bound. The measurement process often gives rise to disturbance of the equilibrium between free and albumin-bound bilirubin, producing erroneous results of unbound bilirubin due to the dissolution of albumi n-bound bilirubin which is the major form of bilirubin present in sera. For the determination of unbound bilirubin, an enzyme horseradish peroxidase is used, either alone [10] or in combination with the diazo method [3] to provide kinetic data for indirect estimation of the original level of unbound serum bilirubin before the start of the kinetic experiment. It is a manual method based on calculation with results strongly affected by sample dilution, chloride concentration and peroxidase activities [11, 12]. Thus, a separation method to remove potential interferents prior to determination of unbound bilirubin is needed. With the generous support of a RGC research grant (HKU 7095/98P) and the Vice Chancellor Outstanding Researcher Award in support of the same project, we had started in 1998 a collabora ted research project involving Hong Kong University and the Chinese Academy of Sciences on developing capillary electrophoresis (CE) for the analysis of unbound bilirubin in sera and cord blood samples of newborn infants. CE was selected due to its very high mass sensitivity with detection at pg levels, the use of an extremely small sample volume lower than 1μL (needed for newborn s with limited supply of blood samples), the capability of measuring unbound bilirubin undisturbed as in the original state in equilibrium with albumin-bound bilirubin by coupling CE with frontal analysis (CE/FA), and the removal of interfering sample matrix using CE with a high separation efficiency. We have presented our results at various international meetings and in clinical and analytical journals over the past 10 years [13-26]. To enable clinical application of the CE/FA method developed, two major obstacles need to be overcome prior to its use for bilirubin management. The first problem is the insufficient sensitivity of the method. To tackle this problem, we have adopted the microfluidic lab-on-a -chip approach using the microelectromechanical system (MEMS) fabrication facilities based on laser ablation at HKU and a joint development with the Academy of Science on construction of instrument for multi-channel high voltage control, we have successfully received a award from RGC last year on developing chemiluminescence detection with microchip capillary electrophoresis for the determination of unbound serum protein in new born babies (HKU 7015/08P). The second problem is the need of a portable bed-side monitoring CE/FA unit to enable an urgent check on unbound bilirubin for an early start on intervention measures, especially during an important early measurement at 6th hours after birth [6,7]. To facilitate the development of a portable bedside CE/FA equipment for clinical application of the method developed, we have used commercially available equipments are used as far as practicable. Thus, the FA separation is carried out in a fused silica capillary of 13 cm length using an absorption wavelen gth at 440 nm by a portable UV/Visible detector . We are seeking the support from the Applied Research Seed Fund to fabricate and develop a bedside monitoring device for clinical management of free bilirubin in serum for new born babies under critical conditions. We have already received the approval from the Hospital Authority to carry out a clinical test at the Queen Mary hospital to obtain preliminary data to confirm the applicability of the device under real clinical environment (see document attached at the end of the application). With the support of the results, we plan to seek support from the Innovation and Technology Fund for a full clinical trial of the methodology dev eloped. The objectives of the proposed project are summarized as follow : i) To design and fabricate a device based on microfluidic chip-capillary electrophoresis for bedside monitoring of free bilirubin in serum for new born babies under critical conditions incorporating the CE/FA mode of separation. ii) To investigate the integration of the currently developed chemilumin escence detection (CL) with microchip capillary electrophoresis for the determination of free bilirubin with unbound serum protein in new born babies iii) Based on above results, to fabricate and test a bedside monitoring device for clinical management of free bilirubin in serum for new born babies under critical conditions. iv) To carry out clinical test at Queen Mary hospital using the device developed to obtain preliminary data to confirm the applicability of the device under real clinical environment. Reference Pooled together with other section and list at the end of section VII. |
| Project Title: | 34th International Symposium on High Performance Liquid Phase Separation and Related Techniques (HPLC 2009) A New Capillary Electrophoresis Buffer For Determining Organic And Inorganic Anions In Electroplating Bath With Surfactant Additives |
| Investigator(s): | Fung YS |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 06/2009 |
| Completion Date: | 07/2009 |
| Abstract: |
| N/A |
| Project Title: | Piezoelectric Quartz Crystal Biosensor For Determining Diagnostic Protein Biomarkers Based on Aptamers Selected By Non-SELEX Using Microfluidic Chip-Capillary Electrophoresis |
| Investigator(s): | Fung YS, Tanner JA, Sun H |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 03/2010 |
| Abstract: |
| Recent development in proteome research leads to a rapid discovery in protein drugs, biomarkers, tumor markers and various functional proteins. Biosensors for important proteins are needed to be developed to deliver quick results for diagnostic and therapeutics applications, which are particularly needed in case of an outbreak in highly infective diseases and for developing diagnostic biomarkers for early cancer detection. The traditional method for clinical protein analysis is immunosensor based on antibody-antigen interaction. However, most monoclonal antibodies are expensive, fragile and often not available for newly discovered proteins. The recent advance of aptamer technology to select specific DNA or RNA sequences with strong binding to target proteins from libraries of typically 1015 DNA sequences provides a promising method for preparing biosensors specific to protein target, as the selected aptamer can be PCR, sequenced and made to sufficient quantities by DNA synthesizers. However, the number of successfully selected aptamers to targeted protein is small and limited to a very few numbers. Both the selectivity and sensitivity of the aptamer-b ased biosensors need improvement for real sample analysis. Recent work using gold nano-particle amplification produces a satisfactory detection limit. However, the additional procedures using amplification and labeling steps prior to analysis makes the biosensor not attractive for real world application. The current method for aptamer selection based on SELEX (Systematic Evolution of Ligands by Exponential Enrichment) suffers problems of high dilution factor and undesirable carry-over for collecting aptamer in each cycle of selection, reducing the probability to detect low-abundant, high protein-binding aptamers. Although the use of CE-SELEX can speed up the selection process, the selectivity of protein target-binding aptamers does not seem to be improved as compared to conventional SELEX selection. In order to reduce the heterogeneity of aptamers selected by conventional SELEX for target proteins, a Non-SELEX selection has been developed to eliminate the PCR step during each selection cycle to avoid heterogeneity amplification during PCR. The selection process uses CE with high separation efficiency for aptamer/target separation and collection of a specific fraction of the eluents in each cycle for subsequent re-cycling and collection (typically 3-4 cycles to complete) under non-equilibrium CE of equilibrium mixtures (NECEEM). Target binding aptamers gradually appear upon cycling after major non-binding fractions are removed in each cycle. However, there is a large dilution (33.3 times) of aptamers upon fraction collection in each cycle which multiples with each additional cycle, giving rise to considerable carry-over from previous fraction, making the final selected fraction highly diluted in aptamer concentration. The less abundant but strong target binding aptamers present in original libraries can escape selection. The proposed microfluidic chip-CE device enables on-chip fraction collection in nL siz e microfluidic channels. Coupled with computer-controlled UV detector-aided switching and various sample stacking methods, the dilution factor are expected to be greatly reduced to increase the probability for collecting low-abundant, high target-binding aptamers. We aim to develop aptasensor based on ssDNA/PQC sensing for direct label-free detection of target proteins using aptamers selected by a microfluidic chip-CE device specially designed and developed in the proposed researc h. To produce a direct label-free aptamer/PQC biosensor for target proteins, we propose to tackle the selectivity and sensitivity problem in the following two directions. For the first direction, a microfluidic chip-CE device for integrating CE separation with on-chip fraction collection will be developed to reduce aptam er dilution upon cycling. This is an extension of our current work for developing microfluidic chip-CE device for on-chip 2D protein separation and collection. Details on the design of the microfluidic chip-CE device and cycling operation will be given in the next section. The fractions collected will be amplified by PCR and tested for their binding strength with target proteins under the CE-frontal analysis (CE-FA) format, a procedure developed from previous RGC grants (RGC 709598P and 701508P) for the determination of free bilirubin under equilibrium of a mixture of albumin/bilirubin for clinical bedside management of free bilirubin to predict the toxicity of hyperbilirubinemia. The CE-FA procedures provide an objective comparison of binding strength of each selected fraction of aptamer with target prot ein under equilibrium to assist the selection of aptamers for biosensor application . The second direction aims to enhance the detection sensitivity of aptamer/PQC biosensor by optimizing sample flow and detection cell volume and improving coating stability and DNA hybridization efficiency using nano-Ag/TiO2. These sensitivity enhancing methods have been developed in previous RGC projects (49696P and 704303P) for developing DNA/PQC biosensor to detect 8 E.coli in drinking wate r. As aptamers are DNA molecules, same sensitivity enhancement are expected which should be sufficient to enable direct and label free detection of target proteins. Both Piezoelectric Quartz Crystal Biosensor and Microfluidic Chip-Capillary Electrophoresis have been developed in Dr Y.S. Fung’s laboratory over the years. Dr J.A. Tanner’s laboratory has developed aptamer technologies for diagnostic and therapeutics purpose, and isolated and purified viral and malarial antigen HRP II proteins for use as protein target for the proposed project. Professor S. Yao’s laboratory has developed PQC and electrochemical sensor for many years and recently active in aptamer electrochemical sensors. With a combined effort from the three research groups, it will form a critical mass leading to a break-through in the apta mer technology for developing Aptamer/PQC biosensors for diagnosis of highly infective diseases and clinically significant protein biomarkers. The objectives of the research are : i) Design, fabricate and assess the Microfluidic chip-Capillary Electrophoresis device for Non-SELEX on-chip fraction collection. ii) Assemble and assess the computer-controlled UV detector -aided High Voltage switching system for fraction collection. iii) Investigate the efficiency of counter gravity flow and isotachophoresis to focus aptamers prior to CE separation. iv) Assess the performance of the system developed for selecting low-abundant, high protein-bin ding aptamers from DNA libraries using Non-SELEX process. v) Assemble, optimize and assess the aptamer-PQC biosensor system under static and flow condition. vi) Determine and compare the analytical performance of aptamer/nano-Ag/TiO2/PQC biosensor in static and flow condition using well characterized proteins. vii) Investigate the scope of application using the optimized aptamer/nano-Ag/TiO2/PQC biosensor under flow condition for different proteins supplied. |
| Project Title: | 25th International Symposium on Microscale Bioseparations (MSB 2010) Coupling Continuous Micro-evaporator to Capillary Electrophoresis for Dete rmination of Organophosphorus Pesticides in vegetables |
| Investigator(s): | Fung YS |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 03/2010 |
| Completion Date: | 03/2010 |
| Abstract: |
| N/A |
| Project Title: | Development of Technology and Applicatio n of High Power/High Energy Lithium Ion Storage Battery |
| Investigator(s): | Fung YS |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Fund Internship Programme |
| Start Date: | 06/2010 |
| Abstract: |
| The project aims at the development and optimization of new Ionic Liquid (IL) systems for high energy/high drain lithium ion battery. |
| List of Research Outputs |
| Chen Q. and Fung Y.S. , Coupling Continuous Micro-evaporator to Capillary Electrophore sis for Determination of Organophosphorus Pesticides in Vegetables, Abstract, 25th International Symposium on Microscale Bioseparations (MSB 2010), March 21-25, 2010, Prague, Czech Republic . 2010, P214. pp167-168. |
| Chen Q. and Fung Y.S. , Determination of Organophosphate Pesticides in Vegetables by Integrating Microextraction with Microfluidic-chip Capillary Electrophoresis, Abstract of the 9th Asia-Pacific International Symp osium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P4-01: pp226. |
| Du F. and Fung Y.S. , Determination of Chlorophenols by Capillary Electrophoresis with Dual Electrode Detection for Peak Purity Assessment, Abstract, 25th International Symposium on Microscale Bioseparations (MSB 2010), March 21-25, 2010, Prague, Czech Republic . 2010, P056, pp88. |
| Du F. and Fung Y.S. , Differential Amperometric Dual Electrode Detection For Peak Purity Assessment Of Polyphenols In Red Wine After Separation By Microfluidic Chip-capillary Electrophoresis, Abstract of the 9th Asia-Pacific International Sy mposium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P3-01: pp212. |
| Fung Y.S. , Chairman, Organizing Committee and Scientific Committee , The 10 th Asia-Pacific International Symposium on Micros cale Separation and Analysis (APCE 2010) to be held in Hong Kong, China, December 10-13, 2010 . 2010. |
| Fung Y.S. , Member of International Advisory Board and Scientific Committee, 9th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2009), Shanghai, China, October 28-31, 2009 . 2009. |
| Fung Y.S. , Member of the Scientific Advisory Council, Separation Science, Eclipse BM, Nantwich, U.K., January 2009- December 2010 . 2010. |
| Fung Y.S. , Member, International Advisory Board and Scienctific Committee , The 9 th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2009) and The 1 st Asian-Pacific international Symposium on Lab-on-Chip (APLOC 2009), October 28-31, 2009 . 2009. |
| Fung Y.S. , Microfluidic Chip-Capillary Electrophoresis for Biomedical Applications , Abstract of Separation Science Singapore, Biopolis Park, Singapore, August 26-28, 2009 . Page 36. |
| Fung Y.S. , Microfluidic Chip-capillary Electrophoresis for Emergent Biomedical Analysis in Hong Kong , The 9 th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2009) and The 1 st Asian-Pacific international Symposium on Lab-on-Chip (APLOC 2009), October 28-31, 2009 . 2009. |
| Guo W. , Lau K.M., Sun H. and Fung Y.S. , Microfluidic Chip-Capillary Electrophoresis for Emergency Onsite Biomedical Analysis, Separation Science . 2010, 2: 3-10. |
| Guo W. , Lau K.M. and Fung Y.S. , Microfluidic Chip-Capillary Electrophoresis for Point-of-Care Analysis, Proceedings, International Symposium on Microchemistry and Microchemistry and Microsystems (ISMM2010), May 28-30, Hong Kong . 2010, P31. |
| Guo W. , Lau K.M. and Fung Y.S. , Microfluidic Chip-capillary Electrophoresis for Emergent Biomedical Analysis in Hong Kong, Abstract of the 9th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, K27: pp36. |
| Guo W. and Fung Y.S. , Profiling of Organic Anions In Urine By Microfluidic Chip-Capillary Electrophoresis, Abstract of the 9th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P4-03: pp228. |
| Mo S. and Fung Y.S. , Solving The Problem of Interference From Hemolysis on The Determination of Free Bilirubin in Human Serum by Capillary Eletrophoresis - Frontal Analysis, Abstract of the 9th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P4-08: pp236. |
| Nie Z. and Fung Y.S. , Determination of Binding Capacity of Albumin for Bilirubin by Microfluidic Chip-capillary Electrophoresis Based on Insitu Titration At a Circular Ferrofluid Driven Micromixer, Abstract of the 9th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P2-02: pp155. |
| Sun H. , Lau K.M. and Fung Y.S. , A New Capillary Electrophoresis Buffer For Determining Organic and Inorganic Anions in Electroplating Bath with Surfactant Additives, Journal of Chromatography A . 2010, 1217: 3244-3250. |
| Sun H. , Nie Z. and Fung Y.S. , Determination of binding capacity of albumin for bilirubin by Microfluidic chip-Capillary Electrophoresis based on insitu titration at a circular ferrofluid driven micromixer, Electrophoresis . 2010. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Development of Molecularly Imprinted Polymer Based Piezoelectric Quartz Crystal Biosensori , Extended Abstract of 12th International Symposium on Electroanalytical Chemistry (12th ISEC), Changchun, China, August 12-15, 2009 . Page 151. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Development of Molecularly Imprinted Polymer based Piezoelectric Quartz Crystal Biosensor, Conference proceeding of the The 12th International Symposium on Electroanalytical Chemistry, August 12-15, 2009, . 2009, 151. |
| Sun H. , Lau K.M. and Fung Y.S. , Hui Sun, Kwokman Lau and Yingsing Fung. A new capillary electrophoresis buffer for determining organic and inorganic anions in electroplating bath with surfactant additives, Journal of Chromatography A . 2010, 1217: 3244-3250. |
| Sun H. and Fung Y.S. , Nucleic Acid Based Piezoelectric Quartz Crystal Biosensor for Dectection of E. Coli , 12th International Symposium on Electroanalytical Chemistry (12th ISEC), Changchun, China, August 12-15, 2009 . 2009. |
| Sun H. and Fung Y.S. , Nucleic Acid Based Piezoelectric Quartz Crystal Biosensor for Detection of E. coli, Extended Abstracts of 12th international Symposium on Electroanalytical Chemistry (12th ISEC), Changchun, China, August 12-15, 2009 . Page 20. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Nucleic Acid Based Piezoelectric Quartz Crystal Bios ensor for Detection of E.coli , Conference Proceeding of The 12th International Symposium on Electroanalytical Chemistry, Changchun, China, August 12-15, 2009 . 20. |
| Sun H. , Albano D.R.B. and Fung Y.S. , Piezoelectric Quartz Crystal Biosensor for Detection of Protein Biomarker for Infective Disease, Conference proceeding of Biosensors 2010, 20th Anniver sary World Congress on Biosensors, Glasgow, United Kingdom, May 28 to May 30, 2010 . P.1.10. |
| Sun H. , Rahula A.D. and Fung Y.S. , Piezoelectric Quartz Crystal Biosensor for Detection of Protein Biomarker for Infective Disease , Abstract, The 20th World Congress on Biosensors (Biosensors 2010), May 26-28, 2010, Glasgow, United Kingdom . 2010, P.1.10. |
| Sze K.L. and Fung Y.S. , Abstract of Microfluidic Capillary Electrophoresis for the Determination of Trace Metals in Milk, 8th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2008), Kaohsiung, Taiwan, November 2-5, 2008 . 2009, P01-03, pp97. |
| Sze K.L. and Fung Y.S. , Capillary Electrophoresis for Trace Metal Determination in Milk, Abstract of the 9th Asia-Pacific International Sym posium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P4-09: pp237. |
| Wu R. and Fung Y.S. , Determination of Lactoferrin and b -lactoglobulin in Dairy Products by Microfluidic-Chip Capillary Electrophoresis, Abstract of the 9th Asia-Pacific International Symposiu m on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P4-10: pp238. |
| Wu R. , Fung Y.S. and Yeung W.S.B. , Microfluidic-chip Capillary Electrophoresis for Analysis of Clinical Urinary Protenis , Abstract, 25th International Symposium on Microscale Bioseparations (MSB 2010), March 21-25, 2010, Prague, Czech Republic . 2010, P136, pp129. |
| Yu C.X., Yuan B.Q., You T.Y. and Fung Y.S. , Determination of Imipramine and Trimipramine by Capillary Electrophoresis with Electrochemiluminescence Detection , Abstract, 25th International Symposium on Microscale Bioseparations (MSB 2010), March 21-25, 2010, Prague, Czech Republic . 2010, P213, pp167. |
| Zhao W. , O W.S. , Fung Y.S. and Cheung M.P.L. , Analysis of mitochondria by capillary electrophoresis: Cardiolipin levels decrease in response to carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone, European Journal of Lipid Science and Technology . 2010, 112: 1058-1066. |
| Zhao W. and Fung Y.S. , Capillary Electrophoresis with LIF Detection for Assessment of Mitochondria Based on teh Cardiolipin Content , Abstract, 25th International Symposium on Microscale Bioseparations (MSB 2010), March 21-25, 2010, Prague, Czech Republic . 2010, P168, pp145-146. |
| Zhao W. and Fung Y.S. , Quantitation of Mitochondrial Event Based on Cardiolipin Content Using Capillary Electrophoresis with Laser Induced Fluorescence Detection, Abstract of the 9th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P4-11: pp239. |
| Zhu D. , Zheng J. and Fung Y.S. , Applicability Study of LiTFSI-Based Room Temperature Ionic Liquids For High Energy Secondary Lithium Ion Battery, Abstract of the 4th Asian Confewrence on Electrochemical Power Sources (ACEP4), November, Taipei, Taiwan, November 8-12, 2009, . 2009, PB04: pp179. |
| Researcher : Ge R |
| List of Research Outputs |
| Ge R. , Chu I.K. and Sun H. , Nuclear-based metallomics in metal-based drugs, "Advanced nuclear analytical techniques for metallomi cs and metalloproteomics" (Edited by C.Y. Chen, Z.F. Chai, YX Gao) . Royal Society of Chemistry, 2010, 265-298. |
| Sun X. , Baker H.M., Ge R. , Sun H. , He Q. and Baker E.N., Crystal structure and metal binding properties of the lipoprotein MtsA, responsible for iron transport in Streptococcus pyogenes , Biochemistry . 2009, 48: 6168-6190. |
| Researcher : Guan X |
| List of Research Outputs |
| Cao Q., Guan X. , George M.W., Phillips D.L. , Ma C. , Kwok W.M., Li M. , Du Y. , Sun X.Z. and Xue J. , Ultrafast Time-resolved Transient Infrared and Resonance Raman Spectroscopic Study of the Photo-deprotection and Rearrangement Reactions of p -Hydroxyphenacyl Caged Phosphates, Faraday Discuss . 2010, 145: 171-183. |
| Du Y. , Xue J. , Li M. , Guan X. , McCamant D.W. and Phillips D.L. , Unravelling the Reaction Mechanism for the Fast Photocyclisation of 2-Benzoylpyridine in Aqueous Solvent by Time-Resolv ed Spectroscopy and Density Functional Theory Calculations, Chemistry - A European Journal . 2010, 16: 6967-6972. |
| El-Khoury P.Z., Kwok W.M., Guan X. , Ma C. , Phillips D.L. and Tarnovsky A.N., Photochemistry of Iodoform in Methanol: Formation and Fate of the Iso -CHl 2 -I Photoproduct , ChemPhysChem . 2009, 10: 1895-1900. |
| Guan X. , NMR Approaches to Protein Conformation and Backbon e Dynamics: Studies on Hyperthermophilic Acylphosphatase and Neuropeptide Secretoneurin (PhD Thesis) . 2010. |
| Ma C. , Kwok W.M., An H. , Guan X. , Fu Y. , Toy P.H. and Phillips D.L. , A Time-Resolved Spectroscopic Study of the Bichromophoric Phototrigger 3', 5'-Dimethoxybenzoin Diethyl Phosphat e: Interaction Between the Two Chromophores Determines the Reaction Pathway, Chemistry - A European Journal . 2010, 16: 5102-5118. |
| Researcher : Guan X |
| List of Research Outputs |
| Cao Q., Guan X. , George M.W., Phillips D.L. , Ma C. , Kwok W.M., Li M. , Du Y. , Sun X.Z. and Xue J. , Ultrafast Time-resolved Transient Infrared and Resonance Raman Spectroscopic Study of the Photo-deprotection and Rearrangement Reactions of p -Hydroxyphenacyl Caged Phosphates, Faraday Discuss . 2010, 145: 171-183. |
| Du Y. , Xue J. , Li M. , Guan X. , McCamant D.W. and Phillips D.L. , Unravelling the Reaction Mechanism for the Fast Photocyclisation of 2-Benzoylpyridine in Aqueous Solvent by Time-Resolved Spectroscopy and Density Functional Theory Calculatio ns, Chemistry - A European Journal . 2010, 16: 6967-6972. |
| El-Khoury P.Z., Kwok W.M., Guan X. , Ma C. , Phillips D.L. and Tarnovsky A.N., Photochemistry of Iodoform in Methanol: Formation and Fate of the Iso -CHl 2 -I Photoproduct , ChemPhysChem . 2009, 10: 1895-1900. |
| Guan X. , NMR Approaches to Protein Conformation and Backbone Dynamics: Studies on Hyperthermophilic Acylphosphatase and Neuropeptide Secretoneurin (PhD Thesis) . 2010. |
| Ma C. , Kwok W.M., An H. , Guan X. , Fu Y. , Toy P.H. and Phillips D.L. , A Time-Resolved Spectroscopic Study of the Bichromophoric Phototrigger 3', 5'-Dimethoxybenzoin Diethyl Phosphate: Interaction Between the Two Chromophores Determines the Reaction Pathway, Chemistry - A European Journal . 2010, 16: 5102-5118. |
| Researcher : Guo W |
| List of Research Outputs |
| Guo W. , Lau K.M., Sun H. and Fung Y.S. , Microfluidic Chip-Capillary Electrophoresis for Emergen cy Onsite Biomedical Analysis, Separation Science . 2010, 2: 3-10. |
| Guo W. , Lau K.M. and Fung Y.S. , Microfluidic Chip-Capillary Electrophoresis for Point-of-Care Analysis, Proceedings, International Symposium on Microchemistr y and Microchemistry and Microsystems (ISMM2010), May 28-30, Hong Kong . 2010, P31. |
| Guo W. , Lau K.M. and Fung Y.S. , Microfluidic Chip-capillary Electrophoresis for Emergent Biomedical Analysis in Hong Kong, Abstract of the 9th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, K27: pp36. |
| Guo W. and Fung Y.S. , Profiling of Organic Anions In Urine By Microfluidic Chip-Capillary Electrophoresis, Abstract of the 9th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P4-03: pp228. |
| Researcher : Han J |
| List of Research Outputs |
| Lai S.W. , Chan Q.K.W. , Han J. , Zhi Y.G. , Zhu N. and Che C.M. , Cyclometalated Pt(II) Complexes bearing Phosphinated Calix[4]arenes, The Sixth National Conference on Coordination Chemistry, The University of Hong Kong, Hong Kong, P. R. China, 6-9 July . 2009. |
| Researcher : Hao Y |
| List of Research Outputs |
| Yang D. , Liu G.J., Hao Y. , Li W. , Dong Z. , Zhang D.W. and Zhu N. , Conformational Studies on Peptides of a -Aminoxy Acids with Functionalized Side-Chains, Chemistry - An Asian Journal . 2010, 5: 1356-1363. |
| Researcher : He Q |
| List of Research Outputs |
| Sun X. , Baker H.M., Ge R. , Sun H. , He Q. and Baker E.N., Crystal structure and metal binding properties of the lipoprotein MtsA, responsible for iron transport in Streptococcus pyogenes , Biochemistry . 2009, 48: 6168-6190. |
| Researcher : He W |
| List of Research Outputs |
| He W. , Yip P.K.T. , Zhu N. and Yang D. , Pd(II)/ t Bu Quinolineoxazoline: An Air-stable And Modular Chiral Catalyst System For Enantioselective Oxidative Cascade Cyclization, Organic Letters . 2009, 11: 5626-5628. |
| Yang D. , Yip P.K.T. , Yang M., He W. , Chen H. , Song K. and Lo K.Y. , Stereoselective Cyclization Reactions through Palladium and Silver Catalysis, The 6th Asian-European Symposium on Metal Mediated Efficient Reactions, Singapore, June 1, 2010 . 2010. |
| Researcher : He X |
| List of Research Outputs |
| He X. , Lam S.W.H. , Zhu N. and Yam V.W.W. , Design and Synthesis of Calixarene-Based Bis-alkynyl-Bridged Dinuclear Au 1 Isonitrile Complexes as Luminescent Ion Probes by the Modulation of Au···Au Interactions, Chemistry - A European Journal . 2009, 15: 8842-8851. |
| He X. , Zhu N. and Yam V.W.W. , Design and Synthesis of Calixarene-based Bis-alkynyl-bridged Dinuclear Au(I) Isonitrile Complexes as Luminescent Ion Probes via the Modulation of Au … Au Interactions, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P218. |
| He X. , Design, Synthesis and Characterization of Alkynyl- and Thiolato- Gold(I) Complexes with Various Receptor Groups for Host-Guest Chemistry (PhD Thesis) . 2010. |
| He X. and Yam V.W.W. , Design, Synthesis, Photophysics, and Ion-binding Studies of a Ditopic Receptor Based on Gold(I) Phosphine Thiolate Complex Functionalized with Crown Ether and Urea Binding Units, Inorganic Chemistry . 2010, 49: 2273-2279. |
| He X. , Cheng C.C. , Zhu N. and Yam V.W.W. , Selective Ion Probe for Mg 2+ Based on Au(I) ... Au(I) Interactions in Tripodal Alkynylgold(I) Complex With Oligoether Pendants, , Chemical Communications . 2009, 4016-4018. |
| He X. , Zhu N. and Yam V.W.W. , Synthesis, Characterization, Structure, and Selective Cu 2+ Sensing Studies of an Alkynylgold(I) Complex Containing the Dipicolylamine Receptor, Organometallics . 2009, 28: 3621-3624. |
| Researcher : He X |
| List of Research Outputs |
| He X. , Lam S.W.H. , Zhu N. and Yam V.W.W. , Design and Synthesis of Calixarene-Based Bis-alkynyl-B ridged Dinuclear Au 1 Isonitrile Complexes as Luminescent Ion Probes by the Modulation of Au···Au Interactions, Chemistry - A European Journal . 2009, 15: 8842-8851. |
| He X. , Zhu N. and Yam V.W.W. , Design and Synthesis of Calixarene-based Bis-alkynyl-bridged Dinuclear Au(I) Isonitrile Complexes as Luminescent Ion Probes via the Modulation of Au … Au Interactions, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P218. |
| He X. , Design, Synthesis and Characterization of Alkynyl- and Thiolato- Gold(I) Complexes with Various Receptor Groups for Host-Guest Chemistry (PhD Thesis) . 2010. |
| He X. and Yam V.W.W. , Design, Synthesis, Photophysics, and Ion-binding Studies of a Ditopic Receptor Based on Gold(I) Phosphine Thiolat e Complex Functionalized with Crown Ether and Urea Binding Units, Inorganic Chemistry . 2010, 49: 2273-2279. |
| He X. , Cheng C.C. , Zhu N. and Yam V.W.W. , Selective Ion Probe for Mg 2+ Based on Au(I) ... Au(I) Interactions in Tripodal Alkynylgold(I) Complex With Oligoether Pendants, , Chemical Communications . 2009, 4016-4018. |
| He X. , Zhu N. and Yam V.W.W. , Synthesis, Characterization, Structure, and Selective Cu 2+ Sensing Studies of an Alkynylgold(I) Complex Containing the Dipicolylamine Receptor, Organometallics . 2009, 28: 3621-3624. |
| Researcher : Ho CM |
| Project Title: | Research and Development of Colorimetric Probes for Reactive Oxygen Species Using Metal Nanopa rticles |
| Investigator(s): | Ho CM, Lok CN |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 06/2009 |
| Completion Date: | 06/2010 |
| Abstract: |
| It is well documented that reactive oxygen species (ROS, such as superoxide, H2O2, hydroxide radical, hydroperoxide and hypochlorous acid) are implicated in various diseases such as inflammation, mutation and cancer [Methods in Enzymology (Ed. Lester Packer), Vol. 105, Academic Press, 1984]. The detection of these ROS plays a crucial role in understanding their mechani stic actions and fates, and in diagnosing diseases. Currently, determination of ROS are relied on organic fluorophore labeling which are sensitive and selective [Haugland, R.P. Handbook of Molecular Probes, 10th Ed. Invitrogen]. However, it should be noted that they are also suffe red from drawbacks, including photobleaching, broad absorption and emission, and a reliance on expensive equipment to analyze their signals. In this connection, the design and development of robust, cheap and selective probes for ROS remains a formidable challenge for chemists. The application of metal nanoparticles (NPs), having at least one dimension in 1 – 100 nm size regime, in bio-diagnostics (e.g. nucleic acids, proteins, cancer) have received mounting interest for the past decade due to their small size and unique optical properties in the visibl e region [Mirkin et al. Chem. Rev. 2005, 105, 1547]. Especially, silver and gold NPs exhibit brilliant color in the visible region that are attributed to their surface plasmon resonances. The position and number of the plasmon bands of a metal are sensitive to particle sizes, shapes, compositions and aggregation states. Notably, their extinction coefficiencies are at least 10,000 times ( ~ 10^9 M-1 cm-1) more sensitive than organic dyes ( ~ 10^4-5 M-1 cm-1). Taking all these advantages together, we envisage that metal NPs would be beneficial to address one or more of the limitatio n imposed by the use of organic fluorophores. With our previous publication record and promising findings, we aim to (1) develop a colorimetric probe for the detection of biological oxidants based on the selective dissolution of Ag from Au/Ag alloy NPs; and (2) examine the biocompatibility and cytotoxicity of Au/Ag alloy NPs toward macrophages through biochemical and proteomic approaches. |
| Project Title: | Oxidation Chemistry of Silver Nanoparti cles |
| Investigator(s): | Ho CM, Che CM, Lok CN |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2010 |
| Abstract: |
| 1) To study the kinetics of oxidation of AgNPs by various biologically relevant oxidants, including hydrogen peroxide, alkyl peroxides, hypochlorous acid and peroxynitrite to the effects of the sizes, shapes, surface coating of the AgNPs on the rates of oxidation will be investigated. The mechanisms of oxidative dissolution of AgNPs will be elucidated. 2) To study the use of AgNPs as a scavenger of reactive oxygen species (ROS, including superoxide, hydrogen peroxide and hypochlorous acid) in biological systems. 3) To develop a colorimetric probe for the detection of biological oxidants based on the selective dissolution of Ag from Au/Ag alloy NPs. 4) To examine the biocompatibility and cytotoxicit y of AgNPs toward macrophages through biochemical and proteomic approaches. |
| Project Title: | Eleventh Tetrahedron Symposium (Tetrahedron 2010) Aerobic Oxidation of Benzylic Amines to Imines Catalyzed by Graphite-Supported Gold Nanoparticles |
| Investigator(s): | Ho CM |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 06/2010 |
| Completion Date: | 06/2010 |
| Abstract: |
| N/A |
| List of Research Outputs |
| Ho C.M. , Zhang J.L., Zhou C. , Chan O.Y. , Yan J. , Zhang F.Y., Huang J.S. and Che C.M. , A Water-Soluble Ruthenium Glycosylated Porphyrin Catalyst for Carbenoid Transfer Reactions in Aqueous Media with Applications in Bioconjugation Reactions, Journal of the American Chemical Society . 2010, 132: 1886-1894. |
| Ho C.M. , Chemical and Biological Properties of Silver Nanoparticles, University of Macau . 2010. |
| Ho C.M. , Yau K.W. , Lok C.N. , So M.H. and Che C.M. , Oxidative Dissolution of Silver Nanoparticles by Biologically Relevant Oxidants. A kinetic and Mechanistic Study, 17th Symposium of Chemistry Postgraduate Research in Hong Kong . 2010. |
| Ho C.M. , Yau K.W. , Lok C.N. , So M.H. and Che C.M. , Oxidative Dissolution of Silver Nanoparticles by Biologically Relevant Oxidants: A Kinetic and Mechanistic Study, Chemistry - An Asian Journal . 2010, 5: 285-293. |
| Liu X. , Lee P.Y. , Ho C.M. , Lui V.C.H. , Chen Y. , Che C.M. , Tam P.K.H. and Wong K.K.Y. , Silver nanoparticles mediate differential responses in keratinocytes and fibroblasts during skin wound healing, ChemMedChem . 2010, 5(3): 468-475. |
| So M.H. , Ho C.M. , Liu Y. and Che C.M. , Aerobic oxidation of benzylic amines to imines catalyzed by graphite-supported gold nanoparticles, Eleventh tetrahedron symopsium . 2010. |
| So M.H. , Liu Y. , Ho C.M. and Che C.M. , Graphite-Supported Gold Nanoparticles as Efficient Catalyst for Aerobic Oxidation of Benzylic Amines to Imines and N-Substituted 1,2,3,4-Tetrahydroisoquinolines to Amides: Synthetic Applications and Mechanistic Study, Chemistry - An Asian Journal . 2009, 4: 1551-1561. |
| So M.H. , Ho C.M. , Chen R. and Che C.M. , Hydrothermal Synthesis of Platinum-Group-Metal Nanoparticles by Using HEPES as a Reductant and Stabilizer, Chemistry - A Asian Journal . 2010, 5: 1322-1331. |
| Wong K.K.Y. , Cheung S.O.F. , Huang L. , Niu J. , Tao C. , Ho C.M. , Che C.M. and Tam P.K.H. , Further evidence of the anti-inflammatory effects of silver nanoparticles, ChemMedChem . 2009, 4(7): 1129-1135. |
| Researcher : Ho KS |
| List of Research Outputs |
| Ho K.S. and Chan W.T. , Time-resolved ICP-MS Measurement of Metals in Single-cell Algae, Colloquium Spectroscopicum Internationale XXXVI, Budapest, Hungary, August 30 - September 3, 2009 (Oral presentation) . 2009. |
| Researcher : Hu H |
| Project Title: | Computer simulation of enzyme catalysis |
| Investigator(s): | Hu H |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 02/2009 |
| Abstract: |
| The purpose of the current project is to develop quantum mechanics and statistical mechanics based simula tion methods and apply them to the modeling of enzyme catalysis. For the simulation of complicated processes such as enzyme catalysis which often involve the interactions of thousands to millions of atoms and span broad region of timescales, we must develop accurate theory to desc ribe the interactions of the molecular system and efficient algorithm to sample the phase space of the molecular system. Even though the combined quantum mechanical/molecular mechanical (QM/MM) methods have shown great potentials in many previous studies of reaction process, the accuracy of the methods is still limited due to the approximations in either the QM theories (e.g., semi-empirical QM instead of ab initio QM) or the samplings (e.g., single-point/ truncated model instead of broad ensemble sampling for the whole system). The current project is aimed to improve on both directions through the systematic development of more accurate and efficient QM/MM methods. The current project also aims to the understanding of the catalytic mechanisms of specific enzymes through the simulation of the catalytic processes, with emphasis on exploring the correlation of conformational dynamics and catalysis in enzymes. The specific objectives of this proposal are: (1) Develop new combined QM/MM method toward multi-scale modeling of biomolecular processes such as molecular recognition, assembling, and catalysis. To understand the molecular mechanism of complex biomolec ular network, it is insufficient for the simulation methods to describe the actions of single molecule. Instead, simulations have to be able to reach out physical events occurring in multiple sites of the molecular complex spanning wide timescales, while still maintain the capability of providing accurate description for chemical processes in specific sites. The two requirements thus motivate us to develop new QM/MM methods toward accurate multi-scale simulation of biomolecular processes. (2) Determine the catalytic mechanisms of the wild-type and mutant chorismate mutase, as well as the phosphorylation-d ependent prolyl isomerase PIN1. The comparison between the catalytic mechanisms and reaction energetics of the molten globular mutant and the well-structured wild-type chorismate mutases will shed light to the coupling between protein folding and enzyme catalysis. The simulation of the PIN1-catalyzed reaction will clarify the mechanism of the largely unknown process of prolyl isomerization. In addition, the simulation will explore the correlation between allostery and catalysis in PIN1. |
| Project Title: | Quantum Mechanical/Molecular Mechanical Simulations of the Role of Conformational Dynamics in Enzyme Catalysis |
| Investigator(s): | Hu H |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 07/2009 |
| Abstract: |
| 1) Develop new combined quantum mechanical/molecular mechanical (QM/MM) method with enhanced phase-space sampling for reaction simulations. For the purpose of studying enzyme conformational dynamics, enhanced sampling technique must be developed to simulate enzyme conformational motions spanning nanosecond to microsecond timescales. 2) Determine the catalytic mechanism of a mutant chorismate mutase. The comparison between the catalytic mechanisms and reaction energetics of the molten globular mutant and the well-structured wild-type enzymes will shed light into the role of conformational dynamics in the catalysis and the coupling between folding and catalysis. 3) Determine the mech anism of the phosphorylation-dependent prolyl isomerase PIN1. The general mechanism of prolyl isomerase, i.e., how enzyme stabilizes the transition state, is largely unknown. QM/MM simulations will provide detailed information about the interactions important for the catalysis. Simulations will address the coupling between conform ational dynamics and catalysis, as suggested in some NMR experiments. Simulations will also explore the effect of the conformati onal motions of the WW domain on the structure, dynamics, and function of the PPIase domain, as a probable correlation between allostery and catalysis. |
| Project Title: | Exploring protein structure-function relationship by designing TIM barrels with varied size and symmetry |
| Investigator(s): | Hu H |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 04/2010 |
| Abstract: |
| TIM barrel, or (alpha/beta)8 barrel, is a conserved protein fold named after triosephosphate isomerase (TIM). Because of the excellent stability of the barrel scaffold, as well as the structural chemical diversity indicated by many distinct reactions catalyzed by many enzymes containing barrel-structured domains, TIM barrel proteins have been a target for intense protein engineerin g and protein design research. Moreover, the evolution process of the TIM barrel domains also becomes an important and challenging question in biochemistry and molecular biology. The objectives of the current research: (1) Investigate the structure and dynamics of the very typical TIM barrel protein fold. The key question we intend to address is whether the size of TIM barrels was shaped by the sizes and chemistries of the ligands of barrel proteins. We plan to address this question from two aspects. On the physical chemistry side, we plan to explore the physical interactions, such as hydrogen bond, dipole-dipole interactions, side-chain packing, and solvations, that determine the size and symmetry of TIM barrel fold. On the bioinformatics side, we like to explore the correlation between biology funct ion, i.e., catalysis for many TIM barrel enzymes, and the size and amino acid compositions of the barrel. (2) Design TIM barrels of varied size and symmetry. We plan to use computational protein design as the tool to design a library of TIM barrel proteins with varied size and symmetry. On one hand, we plan to design a series of proteins that can fold into TIM barrels of sizes ranging from small to big. One of the critical questions we intend to address is what the smallest size for a TIM barrel fold is. The design process can greatly improve our understanding on the structure and stability TIM barrels. On the other hand, we like to explore the structural and/or sequence symmetry in TIM barrels. Even though the barrel possess a topologically 8-fold pseudo-symmetry, TIM barrel proteins rarely adopt an y symmetry in their sequences, perhaps due to either the unfavorable interactions applied by the symmetry, or the difficulty of searching for a small number favored sequence within a limited period of the evolution process. We expect that without the real evolutionary pressure, computer design might be able to discover sequence produce high symmetry on the structure of TIM barrel . (3) On the basis of above two parts of research, we plan to explore further the protein/ligand interactions for the designed TIM barrel proteins. Specifically, we plan to design high-affinity ligand binding sites based on the designed proteins. This will help us understand the physical interactions that contribute to the prote in and ligand binding, furthermore, this work provides foundation for future enzyme design. |
| List of Research Outputs |
| Hu H. and Yang W.T., Elucidating Solvent Contributions to Solution Reactions with Ab Initio QM/MM Methods, Journal of Physical Chemistry B . 2010, 114: 2755-2759. |
| Liu S.B., Hu H. and Pedersen L., Steric, Quantum, and Electrostatic Effects on S N 2 Reaction Barriers in Gas Phase, Journal of Physical Chemistry A . 2010, 114: 5913-5918. |
| Researcher : Hu L |
| Project Title: | Computer-aided drug design for avian-flu virus |
| Investigator(s): | Hu L, Chen G |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 10/2007 |
| Abstract: |
| We propose designing new drugs for avian flu virus target by computer modeling and traditional Chinese medicine (TCM) database. Viruses are usually tough enemies of human being over time such as influenza viruses, HIV and rabies viruses, because viruses mutates very fast to keep themselves evolution and fighting with antiviral drugs and cell immune system. At present, seasonal avian-flu virus H5N1 is threatening our lives. The avian flu H5N1 virus is a quite virulent and fatal virus, which was thought to result from viral reassortment, but pertinent drugs for avian flu virus have not bee n discovered yet until now. The only two available drugs (in the neuraminidase inhibitors class), oseltamivir (commercially known as Tamiflu) and zanamivir (commercially known as Relenza) for seasonal common influenza are expected to be susceptible to H5N1 virus, but the resistanc es to Tamiflu have been found already; and another class of antiviral drugs, inhibitors amantadine and rimantadine, taking membrane ion channel protein M2 as target, could potentially be used against pandemic influenza, however, resistance to these drugs may develop rapidly and th is could significantly limit their effectiveness. Some currently circulating avian H5N1 viral strains are fully resistant to the M2 inhibitors, while others remain fully susceptible. People are worrying about avian flu H5N1 virus would trigger transmission among human, therefore all available drugs are being stocked up in case any emergency. At the same time, a lot of studies have been focused on discovering new drugs for avian-flu viruses. Although traditional Chinese medicine (TCM ) has more than 5,000 year history in China, a lot of principles and methods using in TCM are not understood. TCM modernization is a very improtant and tough task for TCM applications and popularization in the world. Even for western medicince, the combination method in TCM is being tried by researchers to use to develop new way to treat deseases more effectively. Recently, in the combat with viruses TCM is playing more and more important role in the world because of its efficacy, diversity of molecular structures and less side effects comparing with western medicines. To fight with avian-flu viruses, we are going to design new drug candidates steming from TCM database, where the natural compounds with diversified structures provide us more chance to discover new scaffold since discovering new structures in western medicine database is almost dried up. TCM usually has good efficacy and less side effects for antiviral treatment. And once a drug is found in TCM database, which can be applied very quick ly, because the drug might already have clinical trial records. The most recent example is the battle with SARS virus in 2003, the combination TCM and western medicine got best effects when treating SARS patients. This study will extend studies on traditional Chinese medicine and explore TCM in molecular level, which will benefit study on applications of TCM and combination of TCM and western medicine. It is well known every new drug development cost quite long time and billions of dollors. With computer aid, this procedure has been strikingly shortened and resourses can be substantially reduced. This subject has been becoming more and more popular in drug design researches. Our goal is to design new drug candidates by computer-aided drug design by using natual compound structures from TCM database. |
| List of Research Outputs |
| Kao P.Y.P. , Yang D. , Lau L.S. , Tsui H.W., Hu L. , Dai J. , Chan M.P. , Chan C.M. , Wang P. , Zheng B. , Sun J. , Huang J. , Madar J., Chen G. , Chen H. , Guan Y. and Yuen K.Y. , Identification of Influenza a Nucleoprotein as an Ant iviral Target, Nature Biotechnology . 2010, 28: 600-608. |
| Researcher : Hu Y |
| List of Research Outputs |
| Yam V.W.W. , Hu Y. , Chan H.Y. and Chung Y.S.C. , Reversible pH- and Solvent-Responsive Micelle-Mediated Self-Assembly of Platinum(II) Terpyridyl-Based Metallo-Supr amolecular Diblock Copolymers, Chemical Communications . 2009, 6216-6218. |
| Researcher : Huang JS |
| Project Title: | Ruthenium Phthalocyanines with Ruthenium-Nitrogen Multiple Bonds |
| Investigator(s): | Huang JS |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 01/2009 |
| Abstract: |
| (i) To explore a synthetic procedure for ruthenium-n itrogen multiple bonded metallophthalocyanines including quinoneimido, amido, imido, and hydrazido complexes. (ii) To study the spectral and structural features of the ruthenium phthalocyanine complexes described above. (iii) To examine the reactivity of ruthenium-nitrogen multiple bonds regulated by phthalocyanines. (iv) To develop new ruthenium phthalocyanine complexes as catalysts for organic transformations. |
| List of Research Outputs |
| Che C.M. and Huang J.S. , Metalloporphyrin-based oxidation systems: from biomimetic reaction to application in organic synthesis, Chemical Communications . 2009, 3996-4015. |
| Deng Q.H., Chen J., Huang J.S. , Chui S.Y. , Zhu N. , Li G.Y. and Che C.M. , Trapping Reactive Metal Carbene Complexes by a Bis-Pocket Porphyrin. X-ray Crystal Structures of Ru=CHCO2Et and trans-Ru(CHR)(CO) Species and Highly Selective Carbenoid Transfer Reactions, Chemistry - A European Journal . 2009, 15: 10707-10712. |
| Ho C.M. , Zhang J.L., Zhou C. , Chan O.Y. , Yan J. , Zhang F.Y., Huang J.S. and Che C.M. , A Water-Soluble Ruthenium Glycosylated Porphyrin Catalyst for Carbenoid Transfer Reactions in Aqueous Media with Applications in Bioconjugation Reactions, Journal of the American Chemical Society . 2010, 132: 1886-1894. |
| Jiang G.X., Chen J., Huang J.S. and Che C.M. , Highly Efficient Oxidation of Amines to Imines by Single t Oxygen and Its Application in Ugi-Type Reactions, Organic Letters . 2009, 11: 4568-4571. |
| Tsui W.M. , Huang J.S. , Tong S.M. , Kui C.F. , Che C.M. and Zhu N. , Quinoneimido Complexes of a Metalloporphyrin: Isolati on, X-ray Crystal Structures, and DFT Calculations, Chemistry - A Asian Journal . 2010, 5: 759-763. |
| Researcher : Hui SK |
| List of Research Outputs |
| Hui S.K. , Tse M.K. , Yang Y. and Sze K.H. , Backbone and Side-chain 1 H, 13 C and 15 N Assignments of the Ubiquitin-associated Domain of Human X-linked Inhibitor of Apoptosis Protein , Biomol. NMR Assignments . 2010, 4: 13-15. |
| Hui S.K. , Tse M.K. , Wong B.C.Y. and Sze K.H. , Structural and Interaction Study of Ubiquitin-associated (UBA) Domain of XIAP Protein by NMR Spectroscopy, Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic University, Hong Kong, April 24, 2010. . 2010, O-96. |
| Hui S.K. , Tse M.K. , Zhou B., Wong B.C.Y. and Sze K.H. , X-linked Inhibitor of Apoptosis Protein (XIAP) Catches Ubiquitin: Determination of the Solution Structure of Ubiquitin-Associated Domain of Xiap and Mapping its Interaction Sites With Ubiquitin, The Third Asia-Pacific NMR Symposium, Jeju Island, Korea, October 25-28, 2009 . PD18, p220. |
| Researcher : Hung LL |
| List of Research Outputs |
| Au K.M. , Wong M.C. , Chen Z. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , A Novel Class of Bis-cyclometalated Alkynylgold(III) Complexes – Synthesis, Characterization, Photophysics, Electrochemistry and the First Observation of Electrogenerated Chemiluminescence, The 5th International Conference on Gold Science, Technology and its Applications (organized by World Gold Council), Heidelberg, Germany, July 26–29, 2009 . |
| Au K.M. , Chen Z. , Wong M.C. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , Synthesis, Characterization, Photophysical Studies, Electrochemistry and Electrogenerated Chemiluminescence of Bis-cyclometalated Alkynylgold(III) Complexes and their Applications in Organic Light-Emitting Devices, The 42 nd International Union of Pure and Applied Chemis try (IUPAC) Congress, Glasgow, United Kingdom, August 2-7, 2009 . P701_030. |
| Au K.M. , Chen Z. , Wong M.C. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , Synthesis, Characterization, Photophysical Studies, Electrochemistry and the First Observation of Electrogenerated Chemiluminescence of Bis-cyclometalated Alkynylgold(III) Complexes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P217. |
| Researcher : Huo L |
| List of Research Outputs |
| Huo L. and Wong A.O.L. , structure and transcriptional regulation of grass carp calmodulin gene. , Biochem Biophys Res Commun . 2009, 390: 827-833. |
| Researcher : Kan TW |
| List of Research Outputs |
| Ma C. , Kwok W.M. , Chan W.S. , Du Y. , Zuo P. , Kan T.W. , Toy P.H. and Phillips D.L. , Time-Resolved Spectroscopy Studies of the Photodeprotection Reactions of p -Hydroxyphenacyl Ester Phototrigger Compounds, Current Science . 2009, 97: 202-209. |
| Researcher : Ko CB |
| List of Research Outputs |
| Liu Y. , Lok C.N. , Ko C.B. , Shum Y.T. , Wong M.K. and Che C.M. , Subcellular Localization of a Fluorescent Artemisinin Derivative to Endoplasmic Reticulum, Organic Letters . 2010, 12: 1420-1423. |
| Researcher : Ko CC |
| List of Research Outputs |
| Wong H.L. , Ko C.C. , Lam S.W.H. and Yam V.W.W. , Design And Synthesis Of New Classes Of Photochromic Diarylethene-containing Heteroacenes And Their Switchable Luminescence Properties, The 13 th International Symposium on Novel Aromatic Compounds (ISNA-13), Luxembourg City, July 19 – 24, 2009 . 2009, SA028. |
| Wong H.L. , Ko C.C. , Lam S.W.H. , Zhu N. and Yam V.W.W. , Design and Synthesis of a New Class of Photochromic Diarylethene-Containing Dithieno[3,2-b:2’,3’-d]pyrroles and Their Switchable Luminescence Properties, Chemistry - A European Journal . 2009, 15: 10005-10009. |
| Researcher : Ko YY |
| List of Research Outputs |
| Law Y.K. , Wang M. , Ma D.L. , Al-Mousa F., Michelangeli F., Cheng S.H., Ng M., To K.F., Mok O.Y.F., Ko Y.Y. , Lam S.K. , Chen S.F. , Che C.M. , Chiu P. and Ko B.C.B., Alisol B, a novel inhibitor of the SERCA pump, induces autophagy, ER-stress and apoptosis, Molecular Cancer Therapeutics . 2010, 9: 718-730. |
| Researcher : Kong J |
| List of Research Outputs |
| Kong J. , Design, Synthesis, and Photophysical and Electrochemical Studies of Redox-active Macrocyclic Dinuclear Transition Metal Complexes as Potential Molecular Switches (PhD Thesis) . 2009. |
| Researcher : Kong PW |
| List of Research Outputs |
| Ma J. , Peng X. , Cheng K.W. , Kong P.W. , Chu I.K. , Chen S.F. and Wang M. , Effects of melamine on the Maillard reaction between lactose and phenylalanine, 239th ACS National Meeting, San Francisco, CA, United States, March 21-25, AGFD-137, poster. . 2010. |
| Zeng X. , Cheng K.W. , Du Y. , Kong P.W. , Lo C.S.C. , Chu I.K. , Chen S.F. and Wang M. , Activities of hydrocolloids as inhibitors of acrylamide formation in model systems and fried potato strips, Food Chemistry . 2010, 1212: 424-428. |
| Zeng X. , Kong P.W. , Cheng K.W. , Du Y. , Tang Y.S. , Chu I.K. , Lo C.S.C. , Sze K.H. , Chen F. and Wang M. , Direct Trapping of Acrylamide as a Key Mechanism for Niacin's Inhibitory Activity in Carcinogenic Acrylamide Formation, Chemical Research in Toxicology . 2010, 23: 802-807. |
| Researcher : Koo SK |
| List of Research Outputs |
| Koo S.K. , First-principles Simulation of Multi-terminal Carbon-nanotube Based Electronic Devices (MPhil Thesis) . 2010. |
| Researcher : Kui CF |
| Project Title: | Research & Development of New Phosphorescent Platinum(II) Complexes for OLED |
| Investigator(s): | Kui CF, Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 09/2008 |
| Completion Date: | 10/2009 |
| Abstract: |
| The objective of the present project is to develop new phosphorescent platinum(II) complexes for high performance OLED. While platinum(II) complexes containing aromatic N-donor and/or cyclometalated ligands are known to display a variety of emissive excited states including ligand-field (LF), metal-to-ligand charge transfer (MLCT), intraligand (IL) pi-pi*, excimeric sigma*(pi)-sigma(pi*) and oligomeric metal-metal to ligand charge transfer (MMLCT) dsigma*(dz2)-sigma(pi*) ones. The relative energy of these excited states is strongly affected by subtle change in local environment in which the Pt(II) complex is located. Of particular interest is the interplay between the 3MLCT/3IL and 3MMLCT emissive excited states, which are strongly affected by Pt(II)-Pt(II) and/or ligand-ligand interactions. Recently, these kind of Pt(II)-based complexes, such as Pt(II) Schiff Base, [(O^N^N)PtCl] and [(C^N^N)PtCl] , became important phosphorescence materials in OLED fabrication due to their high stability and strong luminescence. In the course of our studies on [(C^N^N)PtX] complexes ((C^N^N) = 6-phenyl-2,2'-bipyridyl, X = Cl, PPh3, acetylide, etc.), we observed that: (1) The (C^N^N) ligand shows a strong preference for planar geometry and can therefore be expected to discourage excited state distortion that promotes radiationless decay. (2) The pi-conjugation and strong pi-donor strength of deprotonated carbon donor of the (C^N^N) ligand increase the energy gap between the d-d and MLCT excited states. (3) The ability to vary the ancillary ligand X and ease of modification of the (C^N^N) ligand are advantageous for structural modification of [(C^N^N)PtX] complexes with tunable photophysical properties. We envision that the intra- and intermolecular interactions between [(C^N^N)Pt]+ moieties can be ramified by enhan cing non-covalent pi•••pi interactions through the use of extended pi-conjugated cyclometalated ligands. Recently, we reported that the extended pi-conjugated cyclometalated C^N^N Pt(II) complexes system ([(C^N^N)PtCl]; C^N^N = 3-(6'-(2"-naphthyl)-2'-pyridyl)isoquinolinyl and derivatives) giving a promoting results in their high thermal stability and strong luminescence (quantum yield up to 0.68). By employing these materials, high performance yellow, orange and white OLED have been fabricated [Che C. M., et. al. Chem. Eur. J., 2007, 13, 417-435.; Che C. M., et. al. Appl. Phys. Lett., 2007, 91, 063508: 1-3.; Che C. M., et. al. Adv. Mater., 2007, 19, 3599-3603.]. We observed that the presence of isoquinoline ring in the C^N^N ligand system is importance for the maintenance of the high thermal stability and strong luminescence properties of their Pt(II) complexes. It may due to the isoquinoline ring can further discourage the excited state distortion that promotes non-radiation decay. However, the low solubility of these extended pi-conjugated cyclometala ted C^N^N Pt(II) complexes would lead to the problems of purification and modification. Furthermore, the price for manufacturing 1 g high purity of [(C^N^N)PtCl] for OLED is very high (e.g. Production cost of 1 g of [(tBu2PhC^N^N)PtCl] = ~ HK$ 2600), it is difficult to apply these materials in commercial OLED products. Through this proposal, we explore new extended pi-conjugated cyclometalated C^N^N Pt(II) complexes system for OLED fabrication that could be (i) structurally roust toward heat treatment and good solubility in organic solvents, (ii) easier to be chemically functionalized for tunable photophysical properties, (iii) purified by easier method with a higher yield, (iv) synthesized by a simple and inexpensive method. In these aspects, we conside red a class of extended pi-conjugated C^N^N ligands which (a) contain chemically functionalizable phenyl ring or other heterocyclic aromatic ring (the naphthalene ring in old extended pi-conjugated cyclometalated C^N^N Pt(II) complexes system is hardly to be functionalize) to synthesize new C^N^N Pt(II) complexes with tunable photophysical properties; (b) add/change the substituen t groups on the extended pi-conjugated C^N^N ligands to increase the solubility of the Pt(II) complexes; (c) develop a new simple synthetic route for producing isoquinoline ring with different substituent groups. |
| List of Research Outputs |
| Che C.M. , Kui C.F. and Kwok C.C. , Platinum (II) Isoqulinoline-Pyridine-Benzene Based Complexes, Methods For Making Same, And Organic Ligh t-Emitting Diodes Including Such Complexes, US Reg Appln no. 12/485388 . US patent, 2009. |
| Tong S.M. , Law Y.C. , Kui C.F. , Zhu N. , Leung K.H., Phillips D.L. and Che C.M. , Ligand-to-Ligand Charge-Transfer Transitions of Plat inum(II) Complexes with Arylacetylide Ligands with Different Chain Lengths: Spectroscopic Characterization, Effect of Molecular Conformations, and Density Functional Theory Calculations, Chemistry - A European Journal . 2010, 16: 6540-6554. |
| Tong S.M. , Kui C.F. , Chao H.Y., Zhu N. and Che C.M. , The 3 [ n d s *( n +1)p s } Emissions of Linear Silver(I) and Gold(I) Chains with Bridging Phosphine Ligands, Chemistry - A European Journal . 2009, 2009: 10777-10789. |
| Tsui W.M. , Huang J.S. , Tong S.M. , Kui C.F. , Che C.M. and Zhu N. , Quinoneimido Complexes of a Metalloporphyrin: Isolation, X-ray Crystal Structures, and DFT Calculations, Chemistry - A Asian Journal . 2010, 5: 759-763. |
| Researcher : Kwok CC |
| List of Research Outputs |
| Che C.M. , Kui C.F. and Kwok C.C. , Platinum (II) Isoqulinoline-Pyridine-Benzene Based Complexes, Methods For Making Same, And Organic Light-Emitting Diodes Including Such Complexes, US Reg Appln no. 12/485388 . US patent, 2009. |
| Che C.M. , Kwok C.C. , Lai S.W. , Rausch A.F., Finkenzeller W.J., Zhu N. and Yersin H., Photophysical Properties and OLED Applications of Phosphorescent Platinum(II) Schiff Base Complexes, Chemistry--A European Journal . 2010, 16: 233-247. |
| Kwok C.C. and Che C.M. , Functional Self-Assembled Zinc(II) Coordination Polymers, Macromolecules Containing Metal and Metal-Like Elements, Volume 10 . 2010, 10: 365-385. |
| Researcher : Kwok WM |
| List of Research Outputs |
| Lai S.W. , Chen Y. , Kwok W.M. , Zhao X.J., To W.P., Fu W. and Che C.M. , Organoplatinum(II) Complexes with Chromophore-Acceptor Dyad Studied by Ultrafast Time-Resolved Absorption Spectroscopy, Chemistry-An Asian Journal . Germany, Wiley-VCH, 2010, 5: 60-65. |
| Ma C. , Kwok W.M. , Chan W.S. , Du Y. , Zuo P. , Kan T.W. , Toy P.H. and Phillips D.L. , Time-Resolved Spectroscopy Studies of the Photodeprotection Reactions of p -Hydroxyphenacyl Ester Phototrigger Compounds, Current Science . 2009, 97: 202-209. |
| Ma C. , Kwok W.M. and Phillips D.L. , Ultrfast Broadband Spectroscopic Study of the Excited States of DNA Oligomers Composed A and / or T, Femtochemistry IX: Femtochemistry, Femtobiology, and Femtophysics -- Frontries in Ultrafast Science and Technology, Beijing, China, August 8-13, 2009 . P-98: 166. |
| Researcher : Lai PM |
| List of Research Outputs |
| Chen X.L., Guo Z.F., Lai P.M. , Sze K.H. and Guo Z.G., Characterization of a Nanaketide Precursor in Biosynth esis of the Nine-Membered Enediyne Core of the Antitumor Antiotic C-1027, Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic Unive rsity, Hong Kong, April 24, 2010. . 2010, O-67. |
| Researcher : Lai SW |
| Project Title: | Phosphorescent supramolecular metal-organic receptors for chemical recognition and biomolecular binding applications |
| Investigator(s): | Lai SW |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2007 |
| Completion Date: | 12/2009 |
| Abstract: |
| (1) This proposal aims to develop supramolecular sensory materials comprising of cyclometalated platinum(II) luminophores as reporting units and functionalized calixarene or cyclodextrin structures as host receptors. The binding motifs will be judiciously designed and incorporated to target different analytes using electrostati c, cation-pi, hydrogen bonding, or hydrophobic pi-pi interactions, and the susceptibility of the absorption and emission energies of these cyclometalated platinum(II) systems to subtle changes in their micro-environments will be utilized as sensory operating principles. The purpos e of this proposal is to integrate inclusion chemistry with phosphorescence. The first objective is: To develop new classes of luminescent probes based on cyclometalated platinum(II) moieties for sensory applications. (2) The second objective is: To explore the sensing capabiliti es towards specific analytes by incorporating appropriate binding motifs into the luminescent receptor. Focus will be given to the conformational changes in the host structures upon inclusion of guest species. This would result in modification of the environment at the cyclometalated Pt(II) luminophoric center, which can subsequently alter the photophysical characteristics. (3) We will utilize the spectrophotometric responses of Pt(II) metallomacrocycles to develop luminescent sensory devices. The binding abilities of the recepto r with guest species will be examined structurally using X-ray crystallography. The selectivity towards various analytes will be investigated, and the binding capacities will be estimated by computational calculations. The third objective is: To determine the sensitivity and selectivity of metal-functionalized host structures towards various substrates based on their spectrophotom etric responses. (4) The fourth objective is: To develop self-assembly processes as efficient methodologies for the construction of metallomacrocycles. An overall aim is to probe the binding mechanisms of luminophoric macrocycles and to develop novel applications as sensory devices, especially for biological systems. In particula r, the development of water-soluble luminescent derivatives which can function as robust sensory materials for molecular recognition and identification of biologically important molecules will be targeted. The significance of this research proposal stems from the implementation of collaborative and interdisciplinary research in the area of photoluminescent biomoleculer sensory tec hnology. |
| Project Title: | Organometallic Photovoltaics Devices |
| Investigator(s): | Lai SW |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 04/2009 |
| Completion Date: | 04/2010 |
| Abstract: |
| This proposal aims to synthesize metal-functionalized pi-conjugated organic molecules as the molecular building blocks, undertake the photophysical studies, and manifest their potential applications towards photovoltaics materials. The purpose of the proposed project is to undertake detailed investigations on the photophysical properties of these complexes, which allows an exploration of new molecular materials with defined structures, novel optical and electronic properties, and impact on the development of molecular electronics. The prope rties of functional molecular materials can be tuned by judicious choice of metal ions and organic ligands. Photophysical measurements will be performed to thoroughly understand the nature of optical characteristics. Through the collaborative research recently initiated between Th e University of Hong Kong and Institute of Chemistry, Chinese Academy of Sciences under the National Natural Science Foundation of China (NSFC)/Hong Kong RGC Joint Research Scheme (N_HKU 752/08), we envisage to explore pi-conjugated organic molecules, which array into structurally defined compounds by self-assembled metal coordination, and to investigate their materials properties towards the fabrication of optoelectronic devices. The key issue of this project is to develop functional molecular materials with ordered structures through self-assembly reactions of molecules of metal-organic compounds of interest, and photo-active supramolecular complexes. Based on the photoluminescent properties of these org anometallic compounds, an essential preliminary screening of luminescent materials as eligible for fabrication of potential photovoltaics devices will be anticipated. To manifest the concept of employing organoplatinum(II) compounds in the development of photovoltaics devices, we will perform device fabrication on these complexes and obtain preliminary results to further improve the device performance accordingly. |
| Project Title: | 5th International Symposium on Macrocyclic & Supramolecular Chemistry Photoluminescent Properties and Singlet Oxygen Production of Cyclometala ted Platinum(II) Complexes bearing Upper-rim Phosphinated Calix[4]arenes |
| Investigator(s): | Lai SW |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 06/2010 |
| Completion Date: | 06/2010 |
| Abstract: |
| N/A |
| List of Research Outputs |
| Che C.M. , Kwok C.C. , Lai S.W. , Rausch A.F., Finkenzeller W.J., Zhu N. and Yersin H., Photophysical Properties and OLED Applications of Phosphorescent Platinum(II) Schiff Base Complexes, Chemistry--A European Journal . 2010, 16: 233-247. |
| Guo Y.B., Zhang Y.J., Liu H.B., Lai S.W. , Li Y.L., Li Y.J., Hu W.P., Wang S., Che C.M. and Zhu D.B., Assembled Organic/Inorganic p−n Junction Interface and Photovoltaic Cell on a Single Nanowire, The Journal of Physical Chemistry Letters . 2010, 1: 327-330. |
| Han J., Chang X. .Y., Zhu L. .R., Pang M. .L., Meng J. .B., Chui S.Y. , Lai S.W. and Vellaisamy A.L.R. , Microwave-assisted Synthesis, Structure, and Tunable Liquid-Crystal Properties of 2,5-Diaryl-1,3,4-Thiadiazole Derivatives trough Peripheral n-Alkoxy Chains, Chemistry, An Asian Journal . 2009, 4: 1099-1107. |
| Lai S.W. , Chan Q.K.W. , Han J. , Zhi Y.G. , Zhu N. and Che C.M. , Cyclometalated Pt(II) Complexes bearing Phosphinated Calix[4]arenes, The Sixth National Conference on Coordination Chemistry, The University of Hong Kong, Hong Kong, P. R. China, 6-9 July . 2009. |
| Lai S.W. and Che C.M. , Cyclometalated Pt(II) Multinuclear Assemblies and Metallomacrocycles: Photophysical Properties and Luminescent Sensing Applications, Global COE Lectureship, Kyoto University, Japan, 3 June . 2010. |
| Lai S.W. , Global COE Lectureship , Kyoto University Global COE program, Japan in June . 2010. |
| Lai S.W. , Chen Y. , Kwok W.M. , Zhao X.J., To W.P., Fu W. and Che C.M. , Organoplatinum(II) Complexes with Chromophore-Acceptor Dyad Studied by Ultrafast Time-Resolved Absorption Spectroscopy, Chemistry-An Asian Journal . Germany, Wiley-VCH, 2010, 5: 60-65. |
| Lai S.W. , Liu Y., Zhang D., Wang B. , Lok C.N. , Che C.M. and Selke M., Photoluminescent Properties and Singlet Oxygen Production of Cyclometalated Platinum(II) Complexes bearing Upper- rim Phosphinated Calix[4]arenes, The Fifth International Symposium on Macrocyclic and Supramolecular Chemistry, Nara Prefecture, Japan, 6-10 June . 2010. |
| Researcher : Lam HY |
| List of Research Outputs |
| Li X. , Lam H.Y. , Zhang Y. and Chan C.K. , Salicylaldehyde Ester-Induced Chemoselective Peptide Ligations: Enabling Generation of Natural Peptidic Linkages at the Serine/Threonine Sites, Organic Letters . 2010, 12: 1724-1727. |
| Researcher : Lam PY |
| List of Research Outputs |
| Liu H. , Lau E. , Lam P.Y. , Chu H. , Li S., Huang G., Guo P., Wang J., Jiang L., Chu I.K. , Lo C.S.C. and Tao Y., OsNOA1/RIF1 is a functional homolog of AtNOA1/RIF1: implication for a highly conserved plant cGTPase essential for chloroplast function., New Phytologist . 2010, 187: 83-105. |
| Siu S.O. , Lam P.Y. , Lau E. , Yeung W.S.B., Cox D.M. and Chu I.K. , Chapter 9: N-Linked Glycoprotein Analysis Using Dual-Extraction Ultrahigh-Preformance Liquid Chromatography and Elec trospray Tandem Mass Spectrometry, In: Jianjun Li , Functional Glycomics -- Methods and Products . 2010. |
| Siu S.O. , Lam P.Y. , Lau E. , Yeung W.S.B. , Cox D.M. and Chu I.K. , N-Linked Glycoprotein Analysis Using Dual-Extraction Ultrahigh-Performance Liquid Chromatography and Electro spray Tandem Mass Spectrometry , Functional Glycomics: Methods and Protocols . 2009, 5: 133-143. |
| Researcher : Lam PY |
| List of Research Outputs |
| Liu H. , Lau E. , Lam P.Y. , Chu H. , Li S., Huang G., Guo P., Wang J., Jiang L., Chu I.K. , Lo C.S.C. and Tao Y., OsNOA1/RIF1 is a functional homolog of AtNOA1/RIF1: implication for a highly conserved plant cGTPase essen tial for chloroplast function., New Phytologist . 2010, 187: 83-105. |
| Siu S.O. , Lam P.Y. , Lau E. , Yeung W.S.B., Cox D.M. and Chu I.K. , Chapter 9: N-Linked Glycoprotein Analysis Using Dual-Extr action Ultrahigh-Preformance Liquid Chromatography and Electrospray Tandem Mass Spectrometry, In: Jianjun Li , Functional Glycomics -- Methods and Products . 2010. |
| Siu S.O. , Lam P.Y. , Lau E. , Yeung W.S.B. , Cox D.M. and Chu I.K. , N-Linked Glycoprotein Analysis Using Dual-Extraction Ultrahigh-Performance Liquid Chromatography and Electrospray Tandem Mass Spectrometry , Functional Glycomics: Methods and Protocols . 2009, 5: 133-143. |
| Researcher : Lam SK |
| Project Title: | Intramolecular and Intermolecular [4+3] Cycloaddition Reactions Using Silyl Enol Aziridin es |
| Investigator(s): | Lam SK, Chiu P |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 10/2008 |
| Completion Date: | 12/2009 |
| Abstract: |
| This project aims to conduct an in depth study on the intermolecular and intramolecular [4+3] cycloaddition reactions of aza-allylcations generated from silyl enol aziridines. By using our proposed cascade reactions, we can combine two or more distinct reactions into a single transformation to afford polycyclic β-amino cycloheptanoids which have 3 new bond formations and bear up to 4 new stereocentres. Our ultimate goal is to increase molecular complexity and definition of some simple molecules in an efficient manner. Moreover, as the cycloadducts have multiple functional groups which occur in many classes of natural products, they have high potential to be further manipulated and transformed for the purpose of total synthesis of bioactive compounds. Thus, we intend to systematically optimize the key parameters, including reaction temperature, solvent effect, the choices of Lewis acids and protection groups of aziridines so as to improve the yields and diastereoselect ivities in these novel [4+3] cycloaddition reactions via aza-allylcation. |
| Project Title: | Mechanistic Analysis Of The Asymmetric [4+3] Cycloaddition Reactions Using Silyl Enol Aziridines |
| Investigator(s): | Lam SK, Chiu P |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 10/2009 |
| Abstract: |
| This project aims to conduct an in depth study in the mechanism of [4+3] cycloaddition reactions to examine if we can refine our method from racemic to chiral version. We postulate that when the optically pure silyl enol aziridines do not fully open under the acidic conditions, the cycloadducts will also be optically active (Please see section VII figure 3 for details). According to some of our preliminary results, our postulate is highly possible. Thus, we are going to synthesize some optically pure silyl enol aziridines to verify our postulate. By using our completely novel cascade reactions, we hope to combine two or more distinct reactions into a single transformation to afford CHIRAL bicyclic β-amino cycloheptanoids wh ich have 3 new bond formations and bear up to 4 new stereocentres. As these cycloheptanoids have multiple functional groups which occur in many classes of natural products, they have high potential to be further manipulated and tr ansformed for the purpose of total synthesis of bioactive medicines. |
| Project Title: | Eleventh Tetrahedron Symposium (Tetrahedron 2010) A Novel Intermolecular [4+3] Cycloaddition of Aziridinyl Enol Silanes with Furan |
| Investigator(s): | Lam SK |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 06/2010 |
| Completion Date: | 06/2010 |
| Abstract: |
| N/A |
| List of Research Outputs |
| Chiu P. and Lam S.K. , Ene Reactions, In: A. de Meijere, Science of Synthesis . Stuttgart, Thieme, 2009, 47: 737-754. |
| Lam S.K. and Chiu P. , A Novel Intermolecular [4+3] Cycloaddition of Aziridinyl Enol Silanes with Furan , The 17th Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic University, Hong Kong, April 24, 2010 . |
| Lam S.K. and Chiu P. , A Novel Intermolecular [4+3] Cycloaddition of Aziridinyl Enol Silanes with Furan , Eleventh Tetrahedron Symposium Frontiers of Organic Chemistry, Beijing, China, June 22, 2010 . PSA185. |
| Law Y.K. , Wang M. , Ma D.L. , Al-Mousa F., Michelangeli F., Cheng S.H., Ng M., To K.F., Mok O.Y.F., Ko Y.Y. , Lam S.K. , Chen S.F. , Che C.M. , Chiu P. and Ko B.C.B., Alisol B, a novel inhibitor of the SERCA pump, induc es autophagy, ER-stress and apoptosis, Molecular Cancer Therapeutics . 2010, 9: 718-730. |
| Shi B., Merten S., Wong D.K.Y., Chu C.K. , Liu L.L. , Lam S.K. , J ä ger A., Wong W.T. , Chiu P. and Metz P., The Rhodium-Catalyzed Carbene Cyclization Cycloaddition Cascade Reaction of Vinylsulfonates, Advanced Synthesis and Catalysis . 2009, 351: 3128-3132. |
| Researcher : Lam ST |
| List of Research Outputs |
| Lam S.T. and Yam V.W.W. , Luminescent Metallogels and Functional Materials of Rhenium(I) Tricarbonyl Diimine Complexes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P215. |
| Lam S.T. , Zhu N. and Yam V.W.W. , Synthesis and Characterization of Luminescent Rhenium(I) Tricarbonyl Diimine Complexes with a Triarylboron Moiety and the Study of Their Fluoride Ion-Binding Properties, Inorganic Chemistry . 2009, 48: 9664-9670. |
| Researcher : Lam SWH |
| Project Title: | Computational Studies on the Photophysical Properties and the Fluxional Behaviour of the Platinum Homodinuclear PtIIPtII and Heterodinuclear PtIIMI (M=Cu, Ag, Au) Alkynyl Complexes |
| Investigator(s): | Lam SWH |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 06/2009 |
| Abstract: |
| 1. To investigate the nature of absorption and emission of the A-frame diplatinum alkynyl complexes as well as the influence of the substituents and the Pt - Pt separation on the spectroscopic properties. In addition, the factors that govern the relative stability of the symmetrical and unsymmetrical forms of the A-fra me complexes will be examined. 2. To elucidate the possible mechanisms for the fluxional processes of the A-frame complexes and to determine the effect of the substituents on the reaction barriers. 3. To investigate the nature of the absorption and emission properties of the heterodinuclear PtIIMI (M= Cu, Ag and Au) alkynyl complexes and the spectral variations as a function of the nature of the metal centers and the substituents on the alkynyl ligands. |
| Project Title: | Computational Studies on the Reactivity of the Binuclear Iridium Complexes with Small Molecules |
| Investigator(s): | Lam SWH |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 06/2010 |
| Abstract: |
| There is considerable current interest in multinuclear metal complexes and in their reactions with small mol ecules, especially with regard to their potential catalytic activity and their relationship to reactions at metal surfaces. The prototype multinuclear system is the binuclear one in which the two metals are in close proximity to one another. In such systems, it is common to use bridging groups to hold the metals together in order to maintain the integrity of the complex during the course of reactions. One class of binuclear comple xes that has been shown to display a rather diverse chemistry utilizes diphosphine ligands such as bis(diphenylphosphino)methane (dppm) or related phosphine groups to bind the two metals. A-frame complexes belong to this class of complexes, in which the metals are bridged by a single ligand in addition to the diphosphine groups, which are mutually trans on each metal. Recently, Cowie and coworkers have reported that binuclear iridium methyl dicarbonyl complex [(dppm)2Ir2(CH3)(CO)2]+ (1) showed a remarkable reactivity upon addition of the substrate molecules such as carbon monoxide, phosphines, sulfur dioxide, alkenes and alkynes. The crystal structure of 1 showed an unsymmetrical A-frame structure in which one carbonyl group is bridging, but the other carbonyl and the methyl group occupy a terminal position on each metal. Inter estingly, based on the NMR study, 1 is highly fluxional in solution. It was suggested that the methyl group was transferred from one metal to the other. Although DFT calculations were performed to study different structural forms of 1 such as the T-shape and the methyl-bridged complexes, the model complex was used in which the phenyl groups of the dppm ligand were replaced by hydrogen. It is possible that the phenyl groups significantly influence the positions of the equatorial ligands through nonbonded contacts, which affect the overall conclusion. In ord er to have a better understanding for the structure and bonding of 1 and the fluxional process, a computational study using the actual complex without any simplification of 1 is required. Upon addition of several small molecules (L) such as carbon monoxide, tert-butyl isocyanid e, phosphines and sulfur dioxide to 1, a facile C-H bond cleavage of the methyl group was observed, yielding the methylene-bridged hydride species, [Ir2H(CO)2(L)(μ-CH2)(dppm)2]+. It has been proposed that C-H bond cleavage at one metal is resulted from ligand binding at the adjacent metal. Presumably, the ligand binding at the adjacent metal increases the electron density at the second metal which facilitates the C-H cleavage of the methyl group. Both the carbonyl and SO2 adducts are fluxional, having the hydrogens of the hydrido ligand and the methylene group exchanging rapidly at ambient temperature, while no exchange for the phosphine and tert-butyl isocyanide adducts was observed. These results indicat e that the barrier for both C-H bond forming and breaking is relatively small and comparable for L = CO and SO2. However, the factors which govern the activation barrier among different ligands remain unclear. It has been reported that 1 reacts readily with a variety of alkyne molecules, including activated alkynes containing electron-withdrawing substituents (e.g. dimethyl acetylene-dicarboxylate), terminal alkynes (e.g. propyne) and non-activated inte rnal alkynes containing various combinations of alkyl and phenyl substituents (e.g. 2-butyne). As observed in the reactions of 1 with the substrates mentioned above, one might expect that alkyne coordination to 1 result in C-H bond cleavage of the methyl group. However, it is not the case. Reaction of 1 with activated alkynes yields simple alkyne adducts, in which the methyl group has remained intact and the alkynes occupy a bridging position parallel to the metals. On the other hand, reaction of 1 with non-activated internal alkynes results in the formation of vinylcarbene products, in which the cleavage of two C-H bonds of the methyl group has occurred, accompanied by condensation of the resulting methylene group at one end of the alkyne linkage and transfer of a hydrogen to the other end. Despite the remarkable reactivites observed, the possible mechani sms for the unusual transformations as well as the factors that govern the different reactivities among the class of alkynes remain unclear. Based on the previous studies, there are in general two possible binding modes of small molecules to the A-frame complexes, in which the molecules could either coordinate to the bridging position (A-frame pocket between the metals) or terminal position (open metal coordination site remote from the bridging site). The reactions of 1 with ethylene and a series of fluoroethylenes were reported. Interestingly, depending upon the degree and position of the fluorine substitution, two olefin binding modes were found, leading to the formation of different products. For the bridging binding mode, the olefin-bridged product was observed, in which th e alkene can be viewed as a dimetallalkane. For the terminal binding mode, methylene-bridged hydride species resulting from C-H activation of the methyl group were observed in some cases, while in other cases, a simple alkene adduct was found. It was reported that the lower fluori ne substitution gave rise to terminal coordination whereas greater substitution favored the bridging mode. Apparently, the steric factor plays a role for the alkene binding site. However, the electronic effect of substituting hydrogens by the much more electronegative fluorines cannot be overlooked. A systematic computational stud y is required in order to gain a better understanding of the factors that controls the binding modes of the alkene to 1 as well as the relative stability of the different products. Objectives: (1) To study the structure and bonding of 1 as well as the fluxional processes occurring in solution, which would provide a better understanding on their corresponding reactivity toward small molecules. (2) To investigate the factors which govern the coordination sites of the substrates to the binuclear iridium complexes, in order to understand the preference of the ligand for the coordination site. (3) To elucidate the factors which control the barrier for the C-H activation of the methyl group in 1 upon ligand coordination, so as to understand why the C-H activation of the methyl group can be induced by several types of ligands, while in some cases the methyl group has remained intact upon ligand coordination. In addition, the possible mechanisms for the reaction of 1 with small molecules to give the corresponding final products will be computed, which will provide a full understa nding of the electronic and steric effects of the substrates on the difference in the reactivities. |
| List of Research Outputs |
| Bennett M.A., Bhargava S.K., Cheng C.C. , Lam S.W.H. , Lee K.M. , Priv é r S.H., Wagler J., Willis A.C. and Yam V.W.W. , Unprecedented Near-Infrared (NIR) Emission in Diplatinum(III) (d 7 -d 7 ) Complexes at Room Temperature, Journal of the American Chemical Society . 2010, 132: 7094-7103. |
| He X. , Lam S.W.H. , Zhu N. and Yam V.W.W. , Design and Synthesis of Calixarene-Based Bis-alkynyl-Bridged Dinuclear Au 1 Isonitrile Complexes as Luminescent Ion Probes by the Modulation of Au···Au Interactions, Chemistry - A European Journal . 2009, 15: 8842-8851. |
| Wong H.L. , Ko C.C. , Lam S.W.H. and Yam V.W.W. , Design And Synthesis Of New Classes Of Photochromic Diarylethene-containing Heteroacenes And Their Switchable Luminescence Properties, The 13 th International Symposium on Novel Aromatic Compounds (ISNA-13), Luxembourg City, July 19 – 24, 2009 . 2009, SA028. |
| Wong H.L. , Ko C.C. , Lam S.W.H. , Zhu N. and Yam V.W.W. , Design and Synthesis of a New Class of Photochromic Diarylethene-Containing Dithieno[3,2-b:2’,3’-d]pyrroles and Their Switchable Luminescence Properties, Chemistry - A European Journal . 2009, 15: 10005-10009. |
| Wong M.C. , Lam S.W.H. , Zhou Z.Y. and Yam V.W.W. , A Luminescent Trinuclear Platinum(II) Pt 3 C 2 System Having a “Naked” C º C 2- Ligand Swapping Amongst Three Unsupported Platinum(II) Moieties, The 42 nd International Union of Pure and Applied Chemistry (IUPAC) Congress, Glasgow, UK, August 2-7, 2009 . P701_43. |
| Wong M.C. , Lam S.W.H. , Zhu N. , Zhou Z.Y. and Yam V.W.W. , Luminescent Polynuclear Alkynylplatinum(II) Complexes with p -Coordination of Various Metal Ions, , The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 (Oral presentation by Dr Keith Man-Chung Wong) . 2009. |
| Researcher : Lam YL |
| List of Research Outputs |
| Chan G.K.Y. , Li F. , Ting S.W. and Lam Y.L. , Mesoporous Carbons as Electrode Materials for Capaci tors and Fuel Cells, 4th Asian Conference on Electrochemical Power Sources , Taipei, Taiwan, October 9-11, 2009 . |
| Chan G.K.Y. , van der Laak N.K. , Li F. , Lam Y.L. , Ting S.W. and Yang C. , Multi-scale Structuring of Composite Electrode Materials for Fuel Cells and Energy Applications, 2nd IWNA International Workshop on Nanotechnology and Application, Vung Tau, Vietnam, November 12-14, 2009 . 2009. |
| Researcher : Lau E |
| List of Research Outputs |
| Liu H. , Lau E. , Lam P.Y. , Chu H. , Li S., Huang G., Guo P., Wang J., Jiang L., Chu I.K. , Lo C.S.C. and Tao Y., OsNOA1/RIF1 is a functional homolog of AtNOA1/RIF1: implication for a highly conserved plant cGTPase essential for chloroplast function., New Phytologist . 2010, 187: 83-105. |
| Siu S.O. , Lam P.Y. , Lau E. , Yeung W.S.B., Cox D.M. and Chu I.K. , Chapter 9: N-Linked Glycoprotein Analysis Using Dual-Extraction Ultrahigh-Preformance Liquid Chromatography and Elect rospray Tandem Mass Spectrometry, In: Jianjun Li , Functional Glycomics -- Methods and Products . 2010. |
| Siu S.O. , Lam P.Y. , Lau E. , Yeung W.S.B. , Cox D.M. and Chu I.K. , N-Linked Glycoprotein Analysis Using Dual-Extraction Ultrahigh-Performance Liquid Chromatography and Electros pray Tandem Mass Spectrometry , Functional Glycomics: Methods and Protocols . 2009, 5: 133-143. |
| Researcher : Lau E |
| List of Research Outputs |
| Liu H. , Lau E. , Lam P.Y. , Chu H. , Li S., Huang G., Guo P., Wang J., Jiang L., Chu I.K. , Lo C.S.C. and Tao Y., OsNOA1/RIF1 is a functional homolog of AtNOA1/RIF1: implication for a highly conserved plant cGTPase essenti al for chloroplast function., New Phytologist . 2010, 187: 83-105. |
| Siu S.O. , Lam P.Y. , Lau E. , Yeung W.S.B., Cox D.M. and Chu I.K. , Chapter 9: N-Linked Glycoprotein Analysis Using Dual-Extrac tion Ultrahigh-Preformance Liquid Chromatography and Electrospray Tandem Mass Spectrometry, In: Jianjun Li , Functional Glycomics -- Methods and Products . 2010. |
| Siu S.O. , Lam P.Y. , Lau E. , Yeung W.S.B. , Cox D.M. and Chu I.K. , N-Linked Glycoprotein Analysis Using Dual-Extraction Ultrahigh-Performance Liquid Chromatography and Electrospray Tandem Mass Spectrometry , Functional Glycomics: Methods and Protocols . 2009, 5: 133-143. |
| Researcher : Law GL |
| List of Research Outputs |
| Law G.L. , Wong K.L. , Man C.W.Y. , Tsao G.S.W. and Wong W.T., A two-photon europium complex as specific endoplasmic reticulum probe., Journal of Biophotonics . 2009, 2(12): 718-724. |
| Law G.L. , Wong K.L., Lau K.K., Sze-To L. , Tanner P.A., Kuo F. and Wong W.T., Nonlinear Optical Activity in Dipolar Organic-lanthanide Complexes, Journal of Material Chemistry . 2010, 20: 4074-4079. |
| Law G.L. , Wong K.L., Tam H.L., Cheah K.W. and Wong W.T., White OLED with a Single-component Europium Complex, Inorganic Chemistry . 2009, 48: 10492-10494. |
| Researcher : Law KL |
| List of Research Outputs |
| Lee O.Y. , Law K.L. and Yang D. , Secondary Amine Formation from Reductive Amination of Carbonyl Compounds Promoted by Lewis Acid Using the InCl 3 /Et 3 SiH System, Organic Letters . 2009, 11: 3302-3305. |
| Researcher : Law YC |
| List of Research Outputs |
| Tong S.M. , Law Y.C. , Kui C.F. , Zhu N. , Leung K.H., Phillips D.L. and Che C.M. , Ligand-to-Ligand Charge-Transfer Transitions of Platinum(II) Complexes with Arylacetylide Ligands with Different Chain Lengths: Spectroscopic Characterization, Effect of Molecular Conformations, and Density Functional Theory Calculations, Chemistry - A European Journal . 2010, 16: 6540-6554. |
| Researcher : Law YK |
| List of Research Outputs |
| Law Y.K. , Wang M. , Ma D.L. , Al-Mousa F., Michelangeli F., Cheng S.H., Ng M., To K.F., Mok O.Y.F., Ko Y.Y. , Lam S.K. , Chen S.F. , Che C.M. , Chiu P. and Ko B.C.B., Alisol B, a novel inhibitor of the SERCA pump, induces autophagy, ER-stress and apoptosis, Molecular Cancer Therapeutics . 2010, 9: 718-730. |
| Law Y.K. , Study on the Idenification of Small Molecule Activators of the Autophagic Pathway and Elucidation of the Mechanism of Action (PhD Thesis) . 2009. |
| Researcher : Lee HM |
| List of Research Outputs |
| Chan D.S.H. , Lee H.M. , Che C.M. , Leung C.H. and Ma D.L. , A Selective Oligonoucleotide-Based Luminescent Switc h-On Probe for the Detection of Nanomolar Mercury(II) ion in Aqueous Solution., Chemical Communications . 2009, 48: 7479-7481. |
| Chan D.S.H. , Lee H.M. , Yang F. , Che C.M. , Wong C.C., Abagyan R., Leung C.H. and Ma D.L. , Structure-Based Discovery of Natural-Product-like TNF-alp ha Inhibitors, Angewandte Chemie International Edition . 2010, 49: 2860-2864. |
| Chan D.S.H. , Lee H.M. , Yang F. , Che C.M. , Wong C.C.L., Abagyan R., Leung C.H. and Ma D.L. , Structure-Based Discovery of Natural-Product-like TNF- a Inhibitors, Angewandte Chemie Internationa l Edition . 2010, 49: 2860-2864. |
| Lee H.M. , Chan D.S.H. , Yang F. , Lam H.Y., Yan S.C., Che C.M. , Ma D.L. and Leung C.H. , Identification of natural product Fonsecin B as a stabilizing ligand of c-myc G-quadruplex DNA by high-throughput virtual screening, Chemical Communications . 2010, 46: 4680-4682. |
| Researcher : Lee KM |
| List of Research Outputs |
| Bennett M.A., Bhargava S.K., Cheng C.C. , Lam S.W.H. , Lee K.M. , Priv é r S.H., Wagler J., Willis A.C. and Yam V.W.W. , Unprecedented Near-Infrared (NIR) Emission in Diplatinum(III) (d 7 -d 7 ) Complexes at Room Temperature, Journal of the American Chemical Society . 2010, 132: 7094-7103. |
| Lee K.M. , Cheng C.C. , Zhu N. and Yam V.W.W. , Novel Air-stable Hexanuclear Gold(I) Phosphinidene Complexes Containing Redox-active Ferrocenyl Units, The 5 th International Conference on Gold Science, Technology and its Applications (organized by World Gold Council),Hei delberg, Germany, July 26–29, 2009 . |
| Researcher : Lee OY |
| List of Research Outputs |
| Lee O.Y. , Law K.L. and Yang D. , Secondary Amine Formation from Reductive Amination of Carbonyl Compounds Promoted by Lewis Acid Using the InCl 3 /Et 3 SiH System, Organic Letters . 2009, 11: 3302-3305. |
| Researcher : Leung CH |
| Project Title: | Regulation of Chemokine Production in Polarized Human Intestinal Epithelial Cells: The Role of Butyrate |
| Investigator(s): | Leung CH |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 03/2008 |
| Completion Date: | 02/2010 |
| Abstract: |
| The overall aim of this proposal is to study the multiple actions of butyrate on the regulation of ch emokines production in intestinal epithelial cells (IECs). Chemokine Production by IECs: Chemokines are a family of peptides that are often secreted by cells. They are chemotactic cytokines that induce directed chemotaxis in nearby responsive cells. Some chemokines are considered pro-inflammatory and can be induced during immune and inflammatory resp onses to promote cells of the immune system to a site of infection. They function mainly as chemoattractants for leukocytes, recruiting monocytes, neutrophils and other effector cells from the blood (Richmond, 2002). Chemokines are classified into four groups (CC, CXC, C and CX3C) according to the number and spacing of cysteine residues in conserved regions. GRO-alpha and IL-8 are members of the CXC chemokine family, which possesses two N-terminal cysteines (C) separated by one amino acid (X). They have been associated with tumor growth, metastasis, angiogenesis and many infl ammatory conditions (Bechara et al., 2007; Richmond, 2002). GRO-alpha and IL-8 induce neutrophil and monocyte chemotaxis, which is important for the immunity (Bocker et al., 2003; Lira et al., 1994). IECs serve as the physical barrier between the body and foreign substances in the intestinal lumen, including food, pathogenic, and non-pathogenic microorganisms. In addition, they are also involved in host defense through the regulation of physiological and pathophysiological processes of the intestinal mucosa, including immunity and inflammation. In this context, IECs play a crucial role in the maintenan ce of intestinal homoeostasis. At the interface between the luminal content and host tissues, the intestinal epithelium must integrate pro- and anti-inflammatory signals to regulate innate and adaptative immune responses, i.e. to control inflammation. For examples, chemokines, which play important roles in immune and inflammatory responses, are eventually produced by IECs in response to potentially harmful substances. In the last few years, advances in immunology, metabolomics and microbial ecology have shown that the contribution of the intestinal microbiota to the overall health status of the host has been so far underestimated. Butyrate-Induced Chemokine Production: Butyrate is the most abundant short chain fatty acid in the intestinal lumen. It is produced during anaerobic fermentation of dietary fiber by intestinal bacteria. Butyrate is multifunctional and is critical for intestinal functions. Butyrate has been reported to inhibit proliferation and induce differentiation in the IEC-like cells (Yamane and Yamane, 2007). Furthermore, there is an increasing body of evidence that shows its importance in the regulation of immune responses. Induction of IL-8 secretion by butyrate in enterocyte-like Caco-2 has been reported previously. The activation of IL-8 promoter was thought to be partially dependent on AP-1 and NF-kappaB (Bocker et al., 2003; Malago et al., 2005). In addition, our pilot study showed that the two NF-kappaB downstream chemokines, IL-8 and GRO-alpha, were induced by butyrate in human intestinal Caco-2 cells (Please see the att ached Preliminary Findings: Fig.1). The molecular mechanism by which butyrate regulates IEC-mediated chemokine production is not fully understood. It is hypothesized that butyrate can have at least two actions in the modulation of CXC chemokine gene expression in IEC. Butyrate was the first histone deacetylase (HDAC) inhibitor identified (Vidali et al., 1978; Candido et al., 1978; Sealy and Chalkley, 1978). Modulation of histone acetylation by butyrate at promoter regions leads to both up- and down- regulation of certain genes, including cytokines and chemokines (Davie, 2003). Study conducted by Fusunyan et al. (1999) indicated that butyrate-induced IL-8 production could be dependent on histone acetylation. In this proposed study, we hypothesize that activation of IL-8 and GRO-alpha promoters could, at least in part, require the acetylation of associated histones. Chemokines such as IL-8 and GRO-alpha are often expressed in response to the induction of NF-kappaB (Nemeth et al., 2004; Richmond, 2002). NF-kappaB response elements identified within the promoter region of these genes were reported to be critical for the induction of gene expression (Feng et al., 2006; Nirodi et al., 2001). We hypothesize that butyrate could trigger the binding of NF-kappaB to the consensus sequences in the promoter regions of the genes and initiate gene transcription. Specific Aims: Enterocyte-like, transwell Caco-2 monolayer has been used for studying drug transport and metabolism in vitro. A modified system established by us was found to be able to tolerate physiological concentratio ns (5 – 24 mM according to Malago et al., 2005) of butyrate and hence, becomes more closely mimic the intestine. Our preliminary data showed that butyrate induced NF-kappaB activity, which plays a central role in immunity and inflammation. Transwell Caco-2 cells that carry the NF-kappaB-driven luciferase gene were treated with up to 16 mM butyrate on the apical side for one week . A dose-dependent increase of NF-kappaB activity was detected using the NF-kappaB-associated luciferase reporter system (Please see the attached Preliminary Findings: Fig.2). This system will be used to examine our hypotheses with the following specific aims: 1. To study the role of NF-kappaB activation in butyrate-induced IL-8 and GRO-alpha gene expression by transwell Caco-2 . 2. To study the impact of butyrate on the transcription of IL-8 and GRO-alpha gene with the focus on the acetylation status of histone associated with the promoter regions. |
| Project Title: | Cyclometalated platinum(II) complexes as targeted immune modulators |
| Investigator(s): | Leung CH, Che CM, Ma DL |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 03/2009 |
| Abstract: |
| Targeted immune modulators form a relatively new class of drugs for a variety of diseases with chronic inflammation and an inappropriate immune response. Tumor necrosis factor-alpha (TNF-alpha) is an essential cytokine regulating the function of the innate immune system and inflammatory responses as a whole, yet has also been recognized as a central pathogenic mediator of a number of chronic and acute diseases. The biology of the TNF-alpha has been extensively studied in expe rimental animals and in humans, particularly with regard to its many activities when expressed at high concentrations in the context of inflammation and disease, such as rheumatoid arthritis, psoriasis, and inflammatory bowel diseases (Tracey et al., 2008). The central mediator in TNF-alpha-initiated inflammatory and immune responses is the transcription factor, nuclear factor-kappaB (NF-kappaB). Activation of NF-kappaB by TNF-alpha has been well studied. In unstimulated cells, NF-kappaB remains largely inactive in the cytoplasm as an NF-kappaB:Ikappa B complex. Binding of TNF-alpha to the TNF receptor (TNFR1 and TNFR2) leads to IkappaB phosphorylation by IKK (IkappaB kinase complex), which mediates IkappaB protein degradation. NF-kappaB then enters the nucleus as a part of transcription complex and regulates the inducible expression of genes (e.g. iNOS) that are involved in inflammation and immune response (Basak and Hoffmann, 2008). The concept arose that elevated concentrations of TNF-alpha at the sites of inflammation were driving disease pathology. The removal of exces s TNF-alpha from sites of inflammation became a therapeutic goal. Development of TNF-alpha antagonists, including commercial biological agents: etanercept, a soluble receptor construct (Enbrel, Amgen Incorporated, Thousand Oaks, CA, Wyeth Pharmaceuticals, Collegeville, PA); infliximab, a chimeric monoclonal antibody (Remicade, Centocor, Horsham, PA, Schering-Plough, Kenilworth, NJ); and adalimumab, a fully human monoclonal antibo dy (Humira, Abbott Laboratories, Abbott Park, IL), has produced significant advances in effective therapy. These drugs inhibit the interaction of TNF-alpha with its receptors through binding to TNF-alpha and are approved for treatment of rheumatoid arthritis (Tracey et al., 2008). Despite considerable incentives, viable leads for small-molecule inhibitors have not been reported. Thus far, small molecule antagonists of TNF-alpha activity have typically been limited to the suppression of functional TNF-alpha level (He et al., 2005). Until recently, a humanized huTNFR1-specific antibody was described recently for selective inhibition of TNF action (Kontermann et al., 2008). The antibody binds to TNFR at the epitope CRD1 that is not responsible for ligand recognition, and hence suppresses TNFR activity by either hindering TNF-alpha binding or inducing conformational change of the receptor. However, disruption of TNF-alpha/TNFRs interaction by small molecules remains a very difficult challenge. A series of cyclometalated platinum(II) complexes with isocyanide ligands was synthesized in Professor Che (co-investigator)’s laboratory. They were well characterized by mass spectrometry, nuclear magnetic resonance spectroscopy and elemental analysis. Some of these complexes exhibit a variety of biological activities (Lai et al., 2002 and unpublished data). Among several selected Pt(II) complexes (Fig. 1), 1c was found to suppress TNF-alpha-mediated NF-kappa B transactivation. Luciferase reporter assay using HepG2 cells stably transfected with NF-kappaB-driven luciferase reporter vector revealed that 1c suppressed NF-kappaB activity in a dose-dependent manner (IC50 ~ 6 uM) (Fig. 2). A selectivity of inhibition by 1c was apparent. Significant effect on the intrinsic NF-kappaB activi ty and that induced by phorbal myristate acetate (PMA) was not observed. Moreover, the complex did not interfere with the activity of three other transcription factors, including CRE, AP-1 and SRE. The mode of inhibition was further investigated by conducting three-dimensional computer simulation analysis (Totrov and Abagyan, 1997). High-throughput docking was performed using the ICM-Pro 3.4-8a program (Molsoft). All continuously flexible ligands were docked into a grid representation of the receptor and assigned a score reflecting the quality of the complex by the ICM method (Molsoft). 1c shows a favorable interaction with the binding site other than the TNF-alpha binding site of the TNFR1 with a binding score = –33.94 (Fig. 3). The complexes are therefore most likely capable of disrupting protei n-protein interactions between TNFR and TNF-alpha by inducing a conformational change of TNF receptor. In addition, no intermolecular hydrogen bonds are formed, suggesting that the interaction is largely hydrophobic and shape-driv en. Nitric oxide is produced by many cells in the body, while its production is thought to have many regulatory roles at each stage of the development of inflammation (Hofseth, 2008). Under normal/basal conditions, nitric oxide is continually being produced by constitutive nitric oxide synthase (cNOS). However, the activity of inducible nitric oxide synthase (iNOS) is stimula ted during inflammation through the activation of NF-kappaB by bacterial endotoxins and cytokines such as TNF-alpha. During inflammation, the amount of nitric oxide produced by iNOS may be a 1,000-fold greater than that produced by cNOS. The iNOS protein therefore has become a potential therapeutic target in inflammatory diseases including rheumatoid arthritis. Reverse-transcription-polymerase chain reaction (RT-PCR) analysis showed that 1c suppressed TNF-alpha-induced expression of iNOS mRNA in a dose dependent manner (Fig. 4). In summary, our preliminary data suggest that cyclometalated platinum(II) complex with isocyanide ligand could be an important scaffold for the development of new anti-inflammatory drugs with a novel mechanism of action and minimum side effects. The ultimate goal of this study is to explore the use of cyclometalated platinum(II) complexes as targeted immune modulators for the treatment of inflammatory diseases. Specifically, we attempt to (i) investiga te the effect of the Pt(II) complex derivatives on TNF-alpha-induced NF-kappaB activity by luciferase reporter assay, (ii) examine the effect of the derivatives on TNF-alpha-media ted iNOS expression and nitric oxide production, (iii) study the Pt(II) complex/TNFR1 interaction, and (iv) establish a pharmacophore model for the design of potent inhibitors in silico. |
| Project Title: | Development of fluorescent biosensors for rapid detection of chloramphenicol residues in seafood |
| Investigator(s): | Leung CH, Ma DL, Ng KM |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Applied Research |
| Start Date: | 06/2009 |
| Abstract: |
| Chloramphenicol (CAP) is a broad spectrum antibiotic isolated in 1947 from Streptomyces venezuelae. It has been used since the 1950s to combat serious human infections and is commonly used in food producing an imals to enhance the production. The International Agency for Research on Cancer (IARC) in 1990 considered CAP as a potential carcinogen. CAP can cause aplastic anemia, which could lead to leukemia. Since CAP-induced aplastic anemia is irreversible and independent of the dosage, it has not been possible to identify a safe level of human exposure to CAP. In addition, CAP affects newborn babies as it can pass through the placental barrier and excreted in breast milk. It induces gray baby syndrome, a pathologic situation that could be fatal up to 40% of the time (1). CAP was banned for use in food-producing animals in USA, Europe and China. A "zero tolerance" has been establis hed by the Food, Drug Administration (FDA) for CAP residues in both domestic and imported animal products (2) including seafood, eggs and milk. However, there is still possibilit y of use of CAP due to its broad spectrum of activity and low cost. Some hairy crabs imported from Yang Cheng Lake in Shanghai to Taiwan contained the antibiotic. Taiwan media reported that some of the hairy crabs imported from the lake contained traces of the antibiotic 10 times higher than the recommended limit. Moreover, the FDA discovered the presence of the antibiotic in the imported Asian shrimp. Hence, it has been stron gly required to develop a rapid and sensitive screening method for this chemical in seafood samples. Several analytical methods have been developed for the detection and quantification of CAP in seafood. They include liquid chromatography (LC), gas chromatography (GC), mass spectrometry (MS), and tandem MS-based techniques (3-7). The FDA approved methods for detection of CAP in seafood are HPLC-MS, GC-ECD (electron capture dete ctor), GC-MS with a detection limit of 5 parts per billion (5 ppb) level in the seafood. Canada and the European Union have refined their methods to detect even the lower levels and should have taken action on food products imported from China and Vietnam, which are reported to be contaminated with CAP. Recently, the methodology has been refined and the sensitivity of methods is increased to detect CAP at 0.3 ppb, which will place the US methodology in line with Canada and European Union. Although the more recent LC/MS/MS methods have improved the sensitivity of the methods, enabling reliable confirmation of CAP residues at <1 ppb levels (6,7), these instrumental methods requir e expensive instruments and high skills for operation, and sample analysis is time consuming. Therefore, development of immunoassays has become attractive because they offer the capability for a rapidly detection of CAP residue at trace levels without laborious sample preparation procedures. Several immunoassays including radio immunoassay, enzyme immunoassays, and chemiluminesc ence immunoassay (8) have been reported in the literature. The reported detection limits are usually depending on the types and size of sample. The first known enzyme immunoassay using rabbit anti-CAP antibody for the detection and quantification of CAP was reported in 1984 (9). Enzyme-linked immunosorbent assay (ELISA) has also been used to screen the presence of CAP in 10 kinds of matrices, including seafood, meat, honey and milk and compared the results with different chroma tography methods. The techniques employed were able to detect CAP residue at the level of 0.1-10 μg/kg in samples (10). More recently, an immunochromatographic assay using colloidal gold-conjugated antibody has been introduced for rapid screening (11). However, this methods cou ld not reach a detection limit of 0.1 g/kg, which is required for monitoring CAP residues in food samples. In addition, cross reactivity of anti-CAP antibody with substances chemically related to CAP such as florfenicol and thiamphenicol is not well defined. The ultimate goal of this proposed work is to develop a rapid and sensitive method for the specific detection of CAP. Specifically, we attempt to (i) generate CAP acetyltr ansferase (CAT)-fluorophore complexes for the specific detection of CAP, (ii) study concentration- and time-dependent fluorescence profiles of the biosensors, and (iii) study the mechanism before and after the addition of CAP by computer modeling. References: 1. Wareham DW & Wilson P. 2002. Chloramphenicol in the 21st century . Hosp Med 63:157-161. 2. FDA. 1982. In Code of federal regulations. Title 21 - Food and drugs. Office of the Federal Register National Archives and Records Service, General Services Administration Washington, D.C.: U.S. Government Printing Office. p. 404-414. 3. Gikas E, Kormali P, Tsipi D & Tsarbopoulos A. 2004. Development of a rapid and sensitive SPE-LC-ESI MS/MS method for the determination of chloramphenicol in seafood. J Agric Food Chem 52:1025-1030. 4. Pfenning AP, Roybal JE, Rupp HS, Turnipseed SB, Gonzales SA & Hurlbut JA. 2000. Simultaneous determination of residues of chloramphenicol, florfenicol, florfenicol amine, and thiamphenicol in shrimp tissue by gas chromatography with electron cap ture detection. J AOAC Int 83:26-30. 5. Takino M, Daishima S & Nakahara T. 2003. Determination of chloramphenicol residues in fish meats by liquid chromatography-atmospheric pressure photoionization mass spectrometry. J Chromatog r A 1011:67-75. 6. Hammack W, Carson MC, Neuhaus BK, Hurlbut JA, Nochetto C, Stuart JS, Brown A, Kilpatrick D, Youngs K, Ferbos K & Heller DN. 2003. Multilaboratory validation of a method to confirm chloramphenicol in shrimp and crabmeat by liquid chromatography-tandem mass spectrometry. J AOAC Int 86:1135-1143. 7. Rupp HS, Stuart JS & Hurlbut JA. 2005. Liquid chromatography/t andem mass spectrometry analysis of chloramphenicol in cooked crab meat. J AOAC Int 88:1155-1159. 8. Lin S, Han SQ, Liu YB, Xu WG & Guan GY. 2005. Chemiluminescence immunoassay for chloramphenicol. Anal Bioanal Chem 382:1250-1255. 9. Campbell GS, Mageau RP, Schwab B & Johnston RW. 1984. Detection and quantitation of chloramphenicol by competitive enzyme-linked immunoassay. Antimicrob Agents Chemother 25:205-211. 10. Shen HY & Jiang HL. 2005. Screening, determination and conf irmation of chloramphenicol in seafood, meat and honey using ELISA, HPLC-UVD, GC-ECD, GC-MS-EI-SIM and GCMS-NCI-SIM methods. Anal chim Acta 535:33-41. 11. Li K, Liu L, Wu CL & Chu XG. 2007. Rapid determination of chloramphenicol residues in aquaculture tissues by immunochromatographic assay. Anal Sci 23:1281-1284. |
| Project Title: | 14th International Congress of Mucosal Immunology (ICMI 2009) Role of Butyrate in Peptidoglycan-mediated Mucosal Immune Response: Regulation of Nucleotide-binding and Oligomerization Domain 2 (NOD2) |
| Investigator(s): | Leung CH |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 07/2009 |
| Completion Date: | 07/2009 |
| Abstract: |
| N/A |
| Project Title: | Platinum-based complexes as sensor s and inhibitors of amyloid-beta for the diagnosis and treatment of Alzheimer’s disease |
| Investigator(s): | Leung CH, Ma DL |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Applied Research |
| Start Date: | 01/2010 |
| Abstract: |
| Alzheimer’s disease (AD) is an irreversible, progressiv e neurodegenerative disorder characterized by three aspects of manifestation: loss of cognitive functions, behavioral disturbances, and daily living difficulties. Risk factors include increasing age, presence of apolipoprotein ε4 gene, Down’s syndrome and female gender. The diseas e currently affects more than five million Americans [1], and, as the most common form of dementia, accounts for 50–60% of the demented population worldwide over the age of 65. In Hong Kong, it is estimated that about 10,810 people are afflicted [2]. The prevalence rate, which doubles for every five years of age above 65, is approximately 6.1% for people over the age of 70 in Hong Kong. Because the world population is aging and AD affects not only patients but also families and caregivers, it could be the most overwhelming healt h issue in this century. One of the primary pathological hallmarks of Alzheimer’s disease is the presence of insoluble neuritic plaques, composed primarily of amyloid-beta (Abeta), in the cerebral cortex. Abeta peptide, a natur al metabolic byproduct, results from the proteolytic cleavage of the amyloid precursor protein, either in the membrane or while undergoing endosomal processing. The resulting 39-42 amino acid long peptides are released into the extracellular space [3]. These species have a strong propensity to aggregate. Many hypothesize that aggregation of Abeta triggers a cascade of events that brings about neuritic dystrophy and neuronal death. Currently, Alzheimer’s disease can only be diagnosed definitively by postmo rtem identification of neuritic plaques and neurofibrillary tangles in the central nervous system tissue. While methods exist for probable premortem diagnosis of AD, including in vivo imaging of the brain with magnetic resonance imaging or functional positron emission tomograph y, along with tests of cognitive and psychological function, reliable methods of premortem diagnosis are needed and may also involve the use of biomarkers of AD such as Abeta. During the past years, body fluids of AD patients are assayed for their content of total or soluble Abeta concentrations using ELISA. A platinum(II)-based complex was recently identified in our laboratory as a luminescent probe for Abeta. There is no cure for AD at present. To alleviate the symptoms, orthodox medications (OM) target neurotransmitter deficits, Abeta neurotoxicity, oxidative damage, and inflammation [4]. The most commonly prescribed drugs are donepezil, rivastigmine, galantamine (cholinesterase inhibitors) or memantine (NMDA antagonist). Though approved by the Food and Drug Administration (FDA) in the US, they are not recommended by the National Institute for Health and Clinical Excellence (NICE) in England andWales, owing to “limited and largely inconclusive” evidence. Nootropic agents such as piracetam, on the other hand, are OM commonly prescribed in Europe for treatment of dementia including AD. Though large-scale clinical trials have shown piracetam to have a high safety profile, the evidence remains insufficient to verify its efficacy [5]. Apart from OM, there are other approaches to treating AD. Some evidence suggests that antioxidants (vitamins E and C) can slowdown the onset ofAD, but these findings should be interpreted with caution, as there is also evidence showing that high dose vitamin E supplementation could increase all-cause mortality [6]. The use of non-steroidal anti-inflammatory drugs (NSAIDs) may reduce the risk of developing AD, but the evidence is incomplete and contradictory [7]. Horm one replacement therapy, once regarded as performing better than tacrine, is no longer recommended, as it may increase the risk of the disease [8]. Given the central role of Abeta in AD, diverse therapeutic strategies that target the generation, disaggregation, and clearance of Abeta are being pursued. Abeta contains a high affinity metal binding site that modulates peptide aggregation and toxicity. Barnham et al [9] have sh own that altering the metal binding activity of Abeta inhibits its neurotoxic activity. Methylation of the imidazole side chains of His-6, -13, and -14, which constitute the high affinity metal binding site, changed Abeta -metal interactions and Abeta:cell binding and rendered the peptide nontoxic. L-PtCl2 (L = 1,10-phenanthroli ne derivatives) complexes, which can target the metal binding site and alkylate the imidazole side chains of Abeta were later found to have therapeutic potential. The ultimate goal of this proposed work is to explore the use of platinum-based compounds as detectors and inhibito rs of Abeta. Specifically, we attempt to (i) investigate the luminescence response of a platinum complex to Abeta and various natural amino acids, (ii) study the binding of the selected platinum complex to Abeta, and (iii) evaluate the impact of platinum complexes on Abeta aggregation. [1] What is Alzheimer’s – introduction, http://www.alz.org/alzheimers disease what is alzheimers.asp [2] Statistics by Country for Alzheimer’s disease: Extrapolation of prevalence rate of Alzheimer’s disease to countries and regions, http://www.wrongdiagnosis.com/a/alzheimers disease/stats-co untry.htm [3] S. Lee, E.J. Fernandez, T.A. Good. Protein Sci (2007) 16:723–732. [4] J. Quinn, J. Kaye, T. Montine and R. Stackman, Phytochemicals in Alzheimer disease: The development of clinical trials, Pharm Biol 42 (2004), 64–73. [5] L. Flicker and G. Grimley Evans, Piracetam for dementia or cognitive impairment, Cochrane Database Syst Rev 1 (2001), CD001011. [6] E.R. Miller 3rd, R. Pastor-Barriuso, D. Dalal, R.A. Riemersma, L.J. Appel and E. Guallar, Meta-analysis: High-dosage vitamin E supplementation may increase all-cause mortality, Ann Intern Med 142 (2005), 37–46. [7] M.K. Samanta, B. Wilson, K. Santhi, K.P.S. Kumar and B. Suresh, Alzhei mer disease and its management: A review, Am J Ther 43 (2006), 516–526. [8] J.L. Cummings, Alzheimer’s disease, N Engl J Med 351 (2004), 56–67. [9] K.J. Barnham, et al., Platinum-based inhibitors of amyloid-b as therapeutic agents for Alzheimer’s disease, Proc Natl Acad Sci U S A 105 (2008), 6813-6818. |
| Project Title: | The role of NOD2 interacting partner HSP90 in the butyrate-dependent intestinal immune response against peptidoglycan |
| Investigator(s): | Leung CH |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 03/2010 |
| Abstract: |
| Dietary fiber not only helps keep people regular, it boosts the immune system so it can better combat inflammatory diseases. When foods high in fiber reach the gut, bacteria convert them to compounds known as short chain fatty acids such as butyrate, which is thought to play increasingly important roles under most conditions [1-3]. Understanding the molecular mechanisms of butyrate action is critical for the im provement of colonic health and the development of treatments for gastrointestinal disorders. Research concerning the role of butyrate in the immune response is therefore highly relevant for both the food industry and the clinical setting. Although short-chain fatty acid production by luminal flora has been implicated in the regulation of intestinal innate immunity and in the pathogenesis of various intestinal diseases [4-7], mechanistic insight into the action of butyrate is currently lacking. Butyrate has been shown to switch the transcriptional pattern of chemokine production through the promotion of histone acetylation [8]. Several studies have also suggested that butyrate could be essential for the regulation of chemokine production mediated by bacterial substances in the intestine [9-12]. We have recently reported an alternative mechanism by which butyrate mediates IL8 and GRO-alpha production by IECs upon PGN stimulation [13]. Based on our findings, we proposed a novel pathway through which butyrate enhances PGN-mediated IL8 and GRO-alpha production. Luminal flora produces butyrate through the fermentation of dietary fibres. The increased butyrate content leads to an accumulation of acetylated histones, thereby triggering NOD2 expression. NOD2, conceivably through cross-talk with TLR2 signalling, induces the expression of IL8 and GRO-alpha in response to PGN via activation of the downstream transcription factor, NF-kappaB. We will extend our work in this study to investigate the mechanism of NOD2 signalling through a proteomic approach. While the majority of the proteomic studies have focused on the mechanisms and potential pathways by which butyrate may suppress tumor growth [14-16], there is minimal knowledge on the role of butyrate in the regulation of innate immunity. A prel iminary study was conducted to identify NOD2-interacting proteins by the 1D gel-based proteomic analysis of anti-NOD2 immunoprecipitates. Proteins that potentially interact with NOD2 upon butyrate treatment are listed in Table 1. HSP90, a molecular chaperone that has previously reported to be critical for NOD2 function [17], was identified to be associated with NOD2 after butyrate treatment. We hypothesize that butyrate-mediated immune response towards PGN stimulation involves NOD2 and its interacting partners including HSP90. A more comprehensive study will be conducted to validate and identify potent ial NOD2 interacting partners. Interacting proteins will be identified by the solution-based multidimensional LC-MS/MS analysis (MudPIT) [18]. Objectives: 1. In collaboration with Dr. Catherine (Co-I), we propose to first verify our preliminary proteomic data on the identification of NOD2 interacting proteins using the multidimensional protein identification (MudPIT) for a global proteomic analysis, which has the ability to identify thousands protein IDs with various categories and wide dynamic ranges that have been previously hard to detect, such as membrane proteins. These studies will also identify additional candidates that could be involved in the molecular actions of butyrate, allowing for future investigations. 2. The second goal of this project is to characterize the interaction between NOD2 and HSP90. The interacting domains will be identified by co-immunoprecipitation assays using IECs that over-express wild-type proteins and deletion mutants. The cellular distribution of NOD2 and HSP90 will be studied by im munocytochemistry. 3. The third goal is to evaluate the role of HSP90 in the PGN-induced chemokine release through the loss-of -function approaches. References: 1. Macdonald TT and Monteleone G. Immunity, inflammation, and allergy in the gut. Science 2005. 307: 1920-1925. 2. Cummings JH, Pomare EW, Branch WJ, Naylor CP and Macfariane GT. Short chain fatty acids in human large intestine, portal, hepatic and venous blood. Gut 1987. 28: 1221–1227. 3. Wong JM, de Souza R, Kendall CW, Emam A and Jenkins DJ. Colonic health: fermentation and short chain fatty acids. J. Clin. Gastroenterol. 2006. 40: 235-243. 4. Fusunyan RD, Quinn JJ, Fujimoto M, MacDermott RP and Sanderson IR. Butyrate switches the pattern of chemokine secretion by intestinal epithelial cells through histone acetylation. Mol. Med. 1999. 5: 631-640. 5. Sanderson IR. Dietary modulation of GALT. J. Nutr. 2007. 137: 2557S-2562S. 6. Hamer HM, Jonkers D, Venema K, Vanhoutvin S, Troost FJ and Brummer RJ. Review article: the role of butyrate on colonic function. Aliment. Pharmacol. Ther. 2008. 27: 104-119. 7. Maslowski KM, Vieira AT, Ng A, Kranich J, Sierro F, Yu D, Schilter HC, Rolph MS, Mackay F, Artis D, Xavier RJ, Teixeira MM and Mackay CR. Regulation of inflammatory responses by gut microb iota and chemoattractant receptor GPR43. Nature 461: 1282-1286. 8. Fusunyan, R. D., Quinn, J. J., Fujimoto, M., MacDermott, R. P. and Sanderson, I. R. Butyrate switches the patte rn of chemokine secretion by intestinal epithelial cells through histone acetylation. Mol. Med. 1999. 5: 631-640. 9. Saegusa S, Totsuka M, Kaminogawa S and Hosoi T. Candida albicans and Saccharomyces cerevisiae induce interleukin -8 production from intestinal epithelial-like Caco-2 cells in the presence of butyric acid. FEMS Immunol. Med. Microbiol. 2004. 41: 227-235. 10. Weng M, Walker WA and Sanderson IR. Butyrate regulates the expression of pathogen-triggered IL-8 in intestinal epithelia. Pediatr. Res. 2007. 62: 542-546. 11. Malago JJ, Koninkx JF, Tooten PC, van Liere EA and van Dijk JE. Anti-inflamma tory properties of heat shock protein 70 and butyrate on Salmonella-induced interleukin-8 secretion in enterocyte-like Caco-2 cells. Clin. Exp. Immunol. 2005. 141: 62-71. 12. Dalmasso G, Nguyen HT, Yan Y, Charrier-Hisamuddin L, Sitaraman SV and Merlin D. Butyrate transcriptionall y enhances peptide transporter PepT1 expression and activity. PLoS ONE 2008. 3:,e2476. 13. Leung CH, Lam W, Ma DL, Gullen EA and Cheng YC. Butyrate mediates NOD2-dependent mucosal immune responses against peptidoglycan. Eur. J. Immunol. 2009 (In Press). 14. Tan HT, Zubaidah RM, Tan S, Hooi SC and Chung MC. 2-D DIGE analysis of butyrate-treated HCT-116 cells after enrichment with heparin affinity chromatography. J. Proteome Res. 2006. 5: 1098–106. 15. Tan S, Seow TK, Liang RC, Koh S, Lee CP, Chung MC and Hooi SC. Proteome analysis of butyrate-treated human colon cancer cells (HT-29). Int. J. Cancer 2002. 98: 523–531. 16. Fung KY, Lewanowitsch T, Henderson ST, Priebe I, Hoffmann P, McColl SR, Lockett T, Head R and Cosgrove LJ. Proteomic analysis of buty rate effects and loss of butyrate sensitivity in HT29 colorectal cancer cells. J Proteome Res. 2009. 8: 1220-1227. 17. Mayor A, Martinon F, De Smedt T, Petrilli V and Tschopp J. A crucial function of SGT1 and HSP90 in inflammasom e activity links mammalian and plant innate immune responses. Nat. Immunol. 2007. 8: 497-503. 18. Washburn MP, Wolters D and Yates JR 3rd. Large-scale analysis of the yeast proteome by multidimensional protein identification technology. Nat. Biotechnol. 2001. 19: 242-247. |
| List of Research Outputs |
| Chan D.S.H. , Lee H.M. , Che C.M. , Leung C.H. and Ma D.L. , A Selective Oligonoucleotide-Based Luminescent Switch-On Probe for the Detection of Nanomolar Mercury(II) ion in Aqueous Solution., Chemical Communications . 2009, 48: 7479-7481. |
| Chan D.S.H. , Lee H.M. , Yang F. , Che C.M. , Wong C.C., Abagyan R., Leung C.H. and Ma D.L. , Structure-Based Discovery of Natural-Product-like TNF-alpha Inhibitors, Angewandte Chemie International Edition . 2010, 49: 2860-2864. |
| Chan D.S.H. , Lee H.M. , Yang F. , Che C.M. , Wong C.C.L., Abagyan R., Leung C.H. and Ma D.L. , Structure-Based Discovery of Natural-Product-like TNF- a Inhibitors, Angewandte Chemie International Edition . 2010, 49: 2860-2864. |
| Lee H.M. , Chan D.S.H. , Yang F. , Lam H.Y., Yan S.C., Che C.M. , Ma D.L. and Leung C.H. , Identification of natural product Fonsecin B as a sta bilizing ligand of c-myc G-quadruplex DNA by high-throughput virtual screening, Chemical Communications . 2010, 46: 4680-4682. |
| Leung C.H. , Discovery of Novel NF-kB inhibitors, Institute of Chinese Medical Sciences, University of Macau . 2010. |
| Leung C.H. , Lam W., Gullen E.A. and Cheng Y.C., Role of Butyrate in Peptidoglycan-mediated Mucosal Immune Response: Regulation of Nucleotide-binding and Oligomerization Domain 2 (NOD2) , 14th International Congress of Mucosal Immunology (ICMI 2009) . 2009. |
| Leung C.H. , Lam W., Ma D.L. , Gullen E.A. and Cheng Y.C., Role of butyrate in the peptidoglycan-mediated mucosal immune response: regulation of nucleotide-binding and oligomerization domain 2 (NOD2)., European Journal of Immunology . 2009, 39: 3529-3537. |
| Sun R.W.Y. , Li C.K.L. , Ma D.L. , Yan J. , Lok C.N. , Leung C.H. , Zhu N. and Che C.M. , Stable anticancer gold(III)-porphyrin complexes: effects of porphyrin structure, Chemistry - A European Journal . 2010, 16: 3097-3113. |
| Wang P. , Leung C.H. , Ma D.L. , Yan S.C. and Che C.M. , Structure-Based Design of Platinum(II) Complexes as c-myc Oncogene Down-regulators and Luminescent Probes for G-quadruplex DNA, 17th Symposium of Chemistry Postgraduate Research in Hong Kong . 2010. |
| Wang P. , Leung C.H. , Ma D.L. , Yan S.C. and Che C.M. , Structure-Based Design of Platinum(II) Complexes as c- myc Oncogene Down-Regulators and Luminescent Probes for G-Quadruplex DNA, , Chemistry - A European Journal . 2010, 16: 6900-6911. |
| Wu P. , Ma D.L. , Leung C.H. , Yan S.C., Zhu N. , Abagyan R. and Che C.M. , Stabilization of G-Quadruplex DNA with Platinum(II) Schiff-base Complexes: Luminescent Probe and Down Regulation of c-myc Oncogene Expression., Chemistry - A European Journal . 2009, 15: 13008-13021. |
| Yan J. , Chow L.F. , Leung C.H. , Sun R.W.Y. , Ma D.L. and Che C.M. , Cyclometalated gold(III) complexes with N-heterocyclic carbene ligands as topoisomerase I poisons , Chemical Communications . Britain, Royal Chemical Society, 2010, 46: 3893 - 3895. |
| Researcher : Leung HC |
| List of Research Outputs |
| Leung H.C. , Syntheses, Reactivities and Biological Activities of Ruthenium Azido, Nitrido and Nitrosyl Complexes Supported by Tetradentate Tertiary Amine Ligands (PhD Thesis) . 2010. |
| Researcher : Leung LT |
| Project Title: | Ring opening of oxabicyclic compounds via a Brook rearrangement |
| Investigator(s): | Leung LT, Chiu P |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 01/2010 |
| Abstract: |
| The project aims to investigate a strategy of cleaving the oxygen bridge in oxabicyclic ketones using silylmetallic reagents to induce ring opening via Brook rearrangement. In this single operation, the oxabicyclic scaffold would be transformed to an opened skeleton, having a hydroxyl group and a silyl enol ether generated in a stereo- and regio-selective manner. To explore the feasibility and scope of this strategy, the effects of using different silylmetallic reagents on different oxapolycyclic systems will be studied. The parameters will be optimized so as to improve the yields and selectivities. Ultimately, this strategy would be developed to be applicable to the synthesis of polycyclic biologically active natural products and drugs. |
| Project Title: | Eleventh Tetrahedron Symposium (Tetrahedron 2010) Ring Opening of Oxabicyclic Compounds via the Brook Rearrangement |
| Investigator(s): | Leung LT |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 06/2010 |
| Completion Date: | 06/2010 |
| Abstract: |
| N/A |
| List of Research Outputs |
| Leung L.T. and Chiu P. , Poster Award, The 11th Tetrahedron Symposium . 2010. |
| Leung L.T. , Ko B.C.B. and Chiu P. , Pseudolaric Acids: Isolation, Bioactivity and Synthetic Studies, Natural Product Reports . Cambridge, UK, Royal Society of Chemistry Publishing, 2010, 26: 1066-1083. |
| Leung L.T. and Chiu P. , Ring Opening of Oxabicyclic Compounds via the Brook Rearrangement, Poster Presentation of Eleventh Tetrahedron Symposium – Frontiers of Organic Chemistry, Elsevier and Tetrahedron Groups of Journals, Beijing, China, June 22, 2010 . |
| Leung L.T. , The Excellent Poster Award, Eleventh Tetrahedron Symposium – Frontiers of Organic Chemistry, Beijing, China, June 25, 2010 . 2010. |
| Researcher : Leung QY |
| List of Research Outputs |
| Chan W.K. , Mak S.K. , Tam W.Y. and Leung Q.Y. , Functional Polymers For Photovoltaic Applications, The 9th International Symposium on Advanced Organic Photonics (ISAOP-9), Bunratty, Ireland . 2009. |
| Mak S.K. , Cheung W.K. , Leung Q.Y. and Chan W.K. , Conjugated Copolymers Containing Low Bandgap Rhenium (I) Complexes, Macromolecular Rapid Communications . Wiley-VCH, 2010, 31: 875-882. |
| Mak S.K. , Wong H.L. , Leung Q.Y. , Tam W.Y. , Chan W.K. and Djurisic A. , The use of sublimable chlorotricarbonyl bis(phenylimi no)acenaphthene rhenium(I) complexes as photosensitizers in bulk-heterojuncti on photovoltaic devices, Journal of Organometallic Chemistry . ELSEVIER SCIENCE SA, 2009, 694: 2770-2776. |
| Mak S.K. , Leung Q.Y. , Li C.H. and Chan W.K. , Tuning the Electronic Properties of Conjugated Polymer by Tethering Low-Bandgap Rhenium(I) Complex on the Main Chain, Journal of Polymer Science Part A: Polymer Chemistry . Wiley Periodicals, Inc., 2010, 48: 2311-2319. |
| Researcher : Leung WH |
| List of Research Outputs |
| Cheung A.S.C. , Pang H.F. , Tam W.S. and Leung W.H. , Laser Spectroscopy of Nil: New Electronic States and Hyperfine Structure, The Journal of Chemical Physics . 2009, 131: 194301-1 - 194301-7. |
| Ma T., Li L. , Leung W.H. and Cheung A.S.C. , Cavity Ring Down Laser Absorption Spectroscopy of NiI, Chinese Journal of Chemical Physics . 2009, 22: 611-614. |
| Researcher : Leung YH |
| List of Research Outputs |
| Djurisic A. , Xie M.H. and Leung Y.H. , Doping of wide band gap nanostructures: ZnO and GaN, In: W. Chen, Doped Nanomaterials and Nanodevices . American Scientific Publishers, 2010, Chapter 4: 101-133. |
| Researcher : Li CH |
| List of Research Outputs |
| Mak S.K. , Leung Q.Y. , Li C.H. and Chan W.K. , Tuning the Electronic Properties of Conjugated Polymer by Tethering Low-Bandgap Rhenium(I) Complex on the Main Chain, Journal of Polymer Science Part A: Polymer Chemistry . Wiley Periodicals, Inc., 2010, 48: 2311-2319. |
| Researcher : Li CKL |
| List of Research Outputs |
| Chow H.M. , Sun R.W.Y. , Lam J.B.B. , Li C.K.L. , Xu A. , Abagyan R., Wang Y. and Che C.M. , A Gold(III) Porphyrin Complex with Antitumor Properties Targets the Wnt/ b -catenin Pathway, Cancer Research . 2010, 70: 329-337. |
| Sun R.W.Y. , Li C.K.L. , Ma D.L. , Yan J. , Lok C.N. , Leung C.H. , Zhu N. and Che C.M. , Stable anticancer gold(III)-porphyrin complexes: effects of porphyrin structure, Chemistry - A European Journal . 2010, 16: 3097-3113. |
| Researcher : Li F |
| List of Research Outputs |
| Chan G.K.Y. , Li F. , Ting S.W. and Lam Y.L. , Mesoporous Carbons as Electrode Materials for Capacitors and Fuel Cells, 4th Asian Conference on Electrochemical Power Sourc es, Taipei, Taiwan, October 9-11, 2009 . |
| Chan G.K.Y. , van der Laak N.K. , Li F. , Lam Y.L. , Ting S.W. and Yang C. , Multi-scale Structuring of Composite Electrode Materials for Fuel Cells and Energy Applications, 2nd IWNA International Workshop on Nanotechnology and Application, Vung Tau, Vietnam, November 12-14, 2009 . 2009. |
| Li F. , van der Laak N.K. , Ting S.W. and Chan G.K.Y. , Varying Carbon Structures Templated From Kit-6 for Optimum Electrochemical Capacitance , Electrochimica Acta . 2010, 55: 2817-2823. |
| Researcher : Li H |
| List of Research Outputs |
| Cheng T. , Li H. , Xia W. and Sun H. , Structure and function study of SlyD in Helicobacter pylori , 21st IUBMB and 12th FAOBMB International Congress of Biochemistry and Molecular Biology, Shanghai, China, August 2-7 . 2009. |
| Wang X. , Du X. , Li H. , Chan D.S.B. and Sun H. , Effect of the N-terminal of the human high affinity copper transporter 1 (hCtr1) on cisplatin hydrolysis and uptake, 14th International Conference on Biological Inorganic Chemistry, Nagoya, Japan, July 25-30 (published in J. Biol. Inorg. Chem. 2009, 14, Suppl 1, P305) . 2009. |
| Xia W. , Li H. , Sze K.H. and Sun H. , Structure of a nickel chaperone, HypA from Helicobacter pylori reveals two distinct metal binding sites, Journal of American Chemical Society . 2009, 131: 10031-10040. |
| Xia W. , Li H. , Sze K.H. and Sun H. , The Bifunctional Roles of Nickel Ions in Helicobacter pylori [NiFe] - Hydrogenase Maturation Pathway, , Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic University, Hong Kong, April 24, 2010 . I-78. |
| Researcher : Li K |
| List of Research Outputs |
| Chen Y. , Li K. , Lu W. , Chui S.Y. , Ma C.W. and Che C.M. , Photoresponsive Supramolecular Organometallic Nanoshee ts Induced by Pt II -- Pt II and C---H ... p Interactions, Angewandte Chemie International Edition . 2009, 48: 9909 –9913. |
| Researcher : Li L |
| List of Research Outputs |
| Ma T., Li L. , Leung W.H. and Cheung A.S.C. , Cavity Ring Down Laser Absorption Spectroscopy of NiI, Chinese Journal of Chemical Physics . 2009, 22: 611-614. |
| Researcher : Li M |
| List of Research Outputs |
| Cao Q., Guan X. , George M.W., Phillips D.L. , Ma C. , Kwok W.M., Li M. , Du Y. , Sun X.Z. and Xue J. , Ultrafast Time-resolved Transient Infrared and Resonance Raman Spectroscopic Study of the Photo-deprotection and Rearrangement Reactions of p -Hydroxyphenacyl Caged Phosphates, Faraday Discuss . 2010, 145: 171-183. |
| Du Y. , Xue J. , Li M. , Guan X. , McCamant D.W. and Phillips D.L. , Unravelling the Reaction Mechanism for the Fast Photocyclisation of 2-Benzoylpyridine in Aqueous Solvent by Time-Resolve d Spectroscopy and Density Functional Theory Calculations, Chemistry - A European Journal . 2010, 16: 6967-6972. |
| Li M. , Wang J. , Ng S.M. , Chan C.Y., He M.L., Yu F. , Lai L., Shi C. , Chen Y.C., Yew D.T., Kung H.F. and Lin M.C. , Adenosine Diphosphate-ribosylation Factor 6 is Required for Epidermal Growth Factor-induced Glioblastoma Cell Proliferation, Cancer . 2009, 115(21): 4959-4972. |
| Li M. , Du Y. , Chuang Y.P. , Xue J. and Phillips D.L. , Water Concentration Dependent Photochemistry of Ketop rofen in Aqueous , Physical Chemistry Chemical Physics . 2010, 12: 4800-4808. |
| Song H.O., Chan T.W. , Li M. , Wong M.C. , Yam V.W.W. and Wu L.X., Synthesis, Characterization and Fluorescence Resonance Energy Transfer (FRET) Studies of Rhenium(I) Complexes With Coumarin Pendants, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P210. |
| Researcher : Li M |
| List of Research Outputs |
| Cao Q., Guan X. , George M.W., Phillips D.L. , Ma C. , Kwok W.M., Li M. , Du Y. , Sun X.Z. and Xue J. , Ultrafast Time-resolved Transient Infrared and Resonance Raman Spectroscopic Study of the Photo-deprotection and Rearrangement Reactions of p -Hydroxyphenacyl Caged Phosphates, Faraday Discuss . 2010, 145: 171-183. |
| Du Y. , Xue J. , Li M. , Guan X. , McCamant D.W. and Phillips D.L. , Unravelling the Reaction Mechanism for the Fast Photocyclisation of 2-Benzoylpyridine in Aqueous Solvent by Time-Resolved Spectroscopy and Density Functional Theory Calculatio ns, Chemistry - A European Journal . 2010, 16: 6967-6972. |
| Li M. , Wang J. , Ng S.M. , Chan C.Y., He M.L., Yu F. , Lai L., Shi C. , Chen Y.C., Yew D.T., Kung H.F. and Lin M.C. , Adenosine Diphosphate-ribosylation Factor 6 is Require d for Epidermal Growth Factor-induced Glioblastoma Cell Proliferation, Cancer . 2009, 115(21): 4959-4972. |
| Li M. , Du Y. , Chuang Y.P. , Xue J. and Phillips D.L. , Water Concentration Dependent Photochemistry of Ketoprofe n in Aqueous , Physical Chemistry Chemical Physics . 2010, 12: 4800-4808. |
| Song H.O., Chan T.W. , Li M. , Wong M.C. , Yam V.W.W. and Wu L.X., Synthesis, Characterization and Fluorescence Resonance Energy Transfer (FRET) Studies of Rhenium(I) Complexes With Coumarin Pendants, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P210. |
| Researcher : Li M |
| List of Research Outputs |
| Cao Q., Guan X. , George M.W., Phillips D.L. , Ma C. , Kwok W.M., Li M. , Du Y. , Sun X.Z. and Xue J. , Ultrafast Time-resolved Transient Infrared and Resonance Raman Spectroscopic Study of the Photo-deprotection and Rearrangement Reactions of p -Hydroxyphenacyl Caged Phosphates, Faraday Discuss . 2010, 145: 171-183. |
| Du Y. , Xue J. , Li M. , Guan X. , McCamant D.W. and Phillips D.L. , Unravelling the Reaction Mechanism for the Fast Photocyclisation of 2-Benzoylpyridine in Aqueous Solvent by Time-Resolved Spectroscopy and Density Functional Theory Calculations, Chemistry - A European Journal . 2010, 16: 6967-6972. |
| Li M. , Wang J. , Ng S.M. , Chan C.Y., He M.L., Yu F. , Lai L., Shi C. , Chen Y.C., Yew D.T., Kung H.F. and Lin M.C. , Adenosine Diphosphate-ribosylation Factor 6 is Required for Epidermal Growth Factor-induced Glioblastoma Cell Proliferation, Cancer . 2009, 115(21): 4959-4972. |
| Li M. , Du Y. , Chuang Y.P. , Xue J. and Phillips D.L. , Water Concentration Dependent Photochemistry of Ketoprofen in Aqueous , Physical Chemistry Chemical Physics . 2010, 12: 4800-4808. |
| Song H.O., Chan T.W. , Li M. , Wong M.C. , Yam V.W.W. and Wu L.X., Synthesis, Characterization and Fluorescence Resonance Energy Transfer (FRET) Studies of Rhenium(I) Complexes With Coumarin Pendants, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P210. |
| Researcher : Li N |
| List of Research Outputs |
| Li N. and Chiu P. , Copper-mediated Reductions Of Unsaturated Thioesters, The 4th International Conference on Cutting-edge Organic Chemistry in Asia . Chulaborn Res. Inst., Bangkok, Thailand, 2009. |
| Li N. , Studies on the Reduction of Unsaturated Thioesters Using Copper Hydride (MPhil Thesis) . 2010. |
| Researcher : Li W |
| List of Research Outputs |
| Bai Y., Li W. , Liu C., Yang Z.H., Feng X., Lu X.H. and Chan G.K.Y. , Stability of Pt Nanoparticles and Enhanced Photocatalytic Performance In Mesoporous Pt-(anatase/TiO 2 (B)) Nanoarchitecture, Journal of Materials Chemistry . 2009, 19: 7055-7061. |
| Li W. , Bai Y., Liu C., Yang Z.H., Feng X., Lu X.H., van der Laak N.K. and Chan G.K.Y. , Highly Thermal Stable and Highly Crystalline Anatase TiO 2 for Photocatalysis, Environmental Science Technology . 2009, 43: 5423-5428. |
| Yang D. , Liu G.J., Hao Y. , Li W. , Dong Z. , Zhang D.W. and Zhu N. , Conformational Studies on Peptides of a -Aminoxy Acids with Functionalized Side-Chains, Chemistry - An Asian Journal . 2010, 5: 1356-1363. |
| Researcher : Li X |
| List of Research Outputs |
| Li X. , Development of New Methodologies in the Chemical Synth esis of (Glyco)Peptides / (Glyco)Proteins, The 6th Sino-US Chemistry Professors Conference, Hangzhou, China, June 14 - June 17, 2010 . |
| Li X. , Chemistry and Biology of Moenomycin and Towards Chemi cal Synthesis of Follicle-Stimulating Hormone, Invited Lecture, Chinese University of Hong Kong, Hong Kong, October 22, 2009 . 2009. |
| Li X. , Chemistry and Biology of Moenomycin and Towards Chemica l Synthesis of Follicle-Stimulating Hormone, Invited Lectures, Shandong University, China,November 29, 2010. 2009 . 2009. |
| Li X. , Development of New Methodologies in Bio-macromolecules Synthesis, Invited Lecture, East China Normal University, Sh anghai, China, June 11, 2010 . 2010. |
| Li X. , Invited Lecture, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, China, June 6, 2010, Development of New Methodologies in Methodologies in Bio-Macromolecules Synthesis . 2010. |
| Li X. , Lam H.Y. , Zhang Y. and Chan C.K. , Salicylaldehyde Ester-Induced Chemoselective Peptide Ligations: Enabling Generation of Natural Peptidic Linkages at the Serine/Threonine Sites, Organic Letters . 2010, 12: 1724-1727. |
| Li X. , Shen B., Yao X.Q., Zhu N. and Yang D. , Self-assembled Synthetic Chloride Channels, The 13th Asian Chemical Congress, Shanghai, China, September 1. 2009 . |
| Li X. , Shen B., Yao X.Q. and Yang D. , Synthetic Chloride Channel Regulates Cell Membrane Potentials and Voltage-Gated Calcium Channels, Journal of the American Chemical Society . 2009, 131: 13676-13680. |
| Li X. , Shen B., Yao X.Q., Zhu N. and Yang D. , Synthetic Chloride Channels, The 25th Naito Conference on “Chemical Biology II” , Hokkaido, Japan, September 1, 2009 . |
| Researcher : Li X |
| Project Title: | Development of Anti-influenza Agents by Inhibiting Hemagglutinin Activities of Influenza A Viruses |
| Investigator(s): | Li X |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 12/2009 |
| Abstract: |
| Influenza is an upper respiratory viral infection that has plagued mankind since time immemorial and it still results in many deaths each year. With the emergence of pandemic spread of 2009 H1N1 swine flu, following the H5N1 avian flu outbreak in 1997, influenza A virus has been causing global concern as a potential pandemic threat. The global outbreak of the 2009 swine flu pandemic has killed 4,700 people worldwide so far from April 2009 to 14 October 2009 according to ECDC Daily Update (European Centre for Disease Prevention and Control). Zanamivir and oseltamivir (tamiflu) are among the most effective drugs to treat avian flu infections. However, viable mutant viruses resistant to them have been isolated. Moreover, the effect of these antiviral drugs to treat new virus subtypes becomes limited. According to the CDC, tamiflu is not very effective in currently circulating seasonal H1N1 virus. Therefo re, there is an urgent need to develop new broad-spectrum antiviral agents acting on additional targets. It is an objective of this proposal to develop a novel strategy to produce anti-influenza inhibitors. We aim to target a class of conserved enzymes of all influenza A viruses to develop a broad-spectrum inhibitor. We are attracted by the viral adhesion process mediated by the carbohydrate-protein interactions between the cell surface and influenza viruses. Influenza A viruses are characteristic of two surface glycoprote ins. HA (hemagglutinin) and NA (neuraminidase). There are 15 subtypes of HA designated H1-H15 and nine of NA, N1-N9. Accordingly, swine flu virus is H1N1 subtype, and avian flu virus belongs to H5N1 subtype. These two glycoproteins (hemagglutinin and neuraminidase) are directly involved in the attachment and detachment of viral particles to and from the host cell, respectively. All known strains of influenza A viruses require a terminal sialic acid on the oligosaccharide of the host cell for the infection. HA shows a lectin-like activity for sialylated oligosaccharides as specific receptors. It recognizes sialyl oligosaccharides expressed on the host cell surface, and attaches viral particles to the host cell through a specific carbohydrate-protein interaction. After virus replication in the infected cell, NA recognizes the sialyl oligosaccharides and catalyzes the hydrolysis of the sialic acid from the host cell surface to allow the virus to escape from the cell during the budding process. Both the entry of viruses into host cell and the release of viruses from the host cell after infection rely on carbohydrate-protein recognizing processes. Therefore, it is considered that disturbing both processes would cause effective inhibition of viral replication. Both zanamivir and oseltamivir (tamiflu) have been successfully effective in the treatment of H5N1 virus by inhibiting the NA hydrolysis of the sialic acid from the cell surface sialyl oligosaccharide. Scheme 1. Design of antiviral agents blocking viral adhesion It is conceivable that chemical agents as HA blockers for inhibiting adhesion of the virus to a host cell would be also therapeutically effective (Scheme 1). Although HA has been identified as a suitable target for therapeutic intervention to halt the progression of influenza viruses, it is fair to say that there has been only modest success in the discovery of compounds that bind tightly to this protein. Herein, we propose to develop a substrate-biased diversity oriented synthesis strategy to prepare a substrate-biased synthetic library. Screening of such chemical library would lead to the identification of potential candidates for blocking influenza viral adhesion to the host cell. |
| List of Research Outputs |
| Li X. , Development of New Methodologies in the Chemical Synthesis of (Glyco)Peptides / (Glyco)Proteins, The 6th Sino-US Chemistry Professors Conference, Hangzhou, China, June 14 - June 17, 2010 . |
| Li X. , Chemistry and Biology of Moenomycin and Towards Chemical Synthesis of Follicle-Stimulating Hormone, Invited Lecture, Chinese University of Hong Kong, Hong Kong, October 22, 2009 . 2009. |
| Li X. , Chemistry and Biology of Moenomycin and Towards Chemical Synthesis of Follicle-Stimulating Hormone, Invited Lectures, Shandong University, China,Novem ber 29, 2010. 2009 . 2009. |
| Li X. , Development of New Methodologies in Bio-macromolecules Synthesis, Invited Lecture, East China Normal University, Shanghai, China, June 11, 2010 . 2010. |
| Li X. , Invited Lecture, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, China, June 6, 2010, Development of New Methodologies in Methodologies in Bio-Macromolecules Synthesis . 2010. |
| Li X. , Lam H.Y. , Zhang Y. and Chan C.K. , Salicylaldehyde Ester-Induced Chemoselective Peptide Ligations: Enabling Generation of Natural Peptidic Linkages at the Serine/Threonine Sites, Organic Letters . 2010, 12: 1724-1727. |
| Li X. , Shen B., Yao X.Q., Zhu N. and Yang D. , Self-assembled Synthetic Chloride Channels, The 13th Asian Chemical Congress, Shanghai, China, September 1. 2009 . |
| Li X. , Shen B., Yao X.Q. and Yang D. , Synthetic Chloride Channel Regulates Cell Membrane Potentials and Voltage-Gated Calcium Channels, Journal of the American Chemical Society . 2009, 131: 13676-13680. |
| Li X. , Shen B., Yao X.Q., Zhu N. and Yang D. , Synthetic Chloride Channels, The 25th Naito Conference on “Chemical Biology II” , Hokkaido, Japan, September 1, 2009 . |
| Researcher : Li X |
| List of Research Outputs |
| Li X. , Development of New Methodologies in the Chemical Synthesis of (Glyco)Peptides / (Glyco)Proteins, The 6th Sino-US Chemistry Professors Conference, Hangzhou, China, June 14 - June 17, 2010 . |
| Li X. , Chemistry and Biology of Moenomycin and Towards Chemical Synthesis of Follicle-Stimulating Hormone, Invited Lecture, Chinese University of Hong Kong, Hong Kong, October 22, 2009 . 2009. |
| Li X. , Chemistry and Biology of Moenomycin and Towards Chemical Synthesis of Follicle-Stimulating Hormone, Invited Lectures, Shandong University, China,November 29, 2010. 2009 . 2009. |
| Li X. , Development of New Methodologies in Bio-macromolecules Synthesis, Invited Lecture, East China Normal University, Shanghai, China, June 11, 2010 . 2010. |
| Li X. , Invited Lecture, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, China, June 6, 2010, Development of New Methodologies in Methodologies in Bio-Macromolecules Synthesis . 2010. |
| Li X. , Lam H.Y. , Zhang Y. and Chan C.K. , Salicylaldehyde Ester-Induced Chemoselective Peptide Ligations: Enabling Generation of Natural Peptidic Linkages at the Serine/Threonine Sites, Organic Letters . 2010, 12: 1724-1727. |
| Li X. , Shen B., Yao X.Q., Zhu N. and Yang D. , Self-assembled Synthetic Chloride Channels, The 13th Asian Chemical Congress, Shanghai, China, September 1. 2009 . |
| Li X. , Shen B., Yao X.Q. and Yang D. , Synthetic Chloride Channel Regulates Cell Membrane Potentials and Voltage-Gated Calcium Channels, Journal of the American Chemical Society . 2009, 131: 13676-13680. |
| Li X. , Shen B., Yao X.Q., Zhu N. and Yang D. , Synthetic Chloride Channels, The 25th Naito Conference on “Chemical Biology II” , Hokkaido, Japan, September 1, 2009 . |
| Researcher : Lin MC |
| Project Title: | Characterizing the antiviral effects and mechanisms of SUPPER INTERFERONS against severe acute respiratory syndrome-coronavirus |
| Investigator(s): | Lin MC, Zheng B |
| Department: | Chemistry |
| Source(s) of Funding: | Research Fund for the Control of Infectious Diseases - Full Grants |
| Start Date: | 09/2007 |
| Completion Date: | 08/2009 |
| Abstract: |
| To identify and characterize the molecular mechan isms and pathways by which these two SUPPER IFNs utilized against SARS-CoV. |
| Project Title: | Molecular mechanisms and signal transduction network of a novel anti-angiogenesis molecule, the kringle 1 domain of Human Hepatocyte Growth Factor (HGFK1) |
| Investigator(s): | Lin MC, Ng SM, Yiu SM |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 09/2007 |
| Completion Date: | 07/2010 |
| Abstract: |
| To determine and validate the molecular mechanisms and down-stream targets underlying the potent anti-a ngiogenesis activity of HGFK1 in tumor-derived microvascular endothelial cells by cDNA microarray studies; to predict and valida te the signal transduction networks by bioinfomatic analysis and molecular biology approaches; to achieve maximal therapeutic effect by combining rAAV-HGFK1 with rAAV-endostatin, and with chemotherapy, for the treatment of HCC and cancer metastasis. |
| Project Title: | The functional role of cell cycl e-related kinase in embryonic development |
| Investigator(s): | Lin MC, Ng SM |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 05/2008 |
| Abstract: |
| Most eukaryotic cell cycle transitions are controlled by various cyclin-dependent kinase (CDK) complexes formed between a CDK and a regulatory cyclin subunit. For full activation, CDK requires dephosphorylation at the inhibitory sites (e.g. Tyr-15 in human CDK2) by CDC25 phosphatases and phosphorylation at a conserved threonine residue (e.g. Thr 160 in human CDK2) by another kinase known as CDK-activating kinase (CAK). In mammalian cells, CAK is a trimeric complex consisting of a cat alytic subunit CDK7 (a regulatory subunit), cyclin H and an assembly factor, MAT1 (ménage a trios) (Poon et al., 1993; Solomon et al., 1993; Fisher and Morgan, 1994). Cell cycle related kinase (CCRK), also known as p42 or CDK-related kinase PNQALRE, is a newly identified 42 kDa protein which contains all 11 conserved subdomain s characteristic of serine/threonine protein kinase. It shares the highest amino acid sequence identity with CDK1, CDK2, and CDK7. Previously, Liu et al. showed in human cervical carinoma HeLa cells that CCRK acted as a CAK by phosphorylating and activating Cdk2 (Liu et al., 2004). Moreover, they found that CCRK was indispensable for HeLa cell growth and was expressed in various cancer cell lines including including cervical adenocarcinoma (HeLa), osteogenic sarcoma (U2OS), and breast adenocarcinoma (MCF-7). However, Wohlbold et al. later demonstrated that although depletion of CCRK in human colorectal carcinoma (HCT116) and osteosarcoma (U2OS) cells impai red cell proliferation, the intrinsic kinase activity of CCRK appeared to be weak and the modest CAK activity detected may due to its apparent association with Cdk 7 (Wohlbold et al., 2006). Therefore, the question of whether CCRK is a second CAK on top of CDK 7 is still controversial. Recently, we have identified that CCRK is an oncogene in human glioblastoma (Ng et al., 2007). We found that CCRK is upregulated in both GBM patient samples and cell lines. Importantly, down-regulation of CCRK by specific siRNA (siCCRK) reduces GBM cell growth and tumorigenicity, whereas overexpression of CCRK triggers the malignant conver sion of a non-tumorigenic GBM cell line. The oncogenic activitity of CCRK is mediated at least in part through CDK2 activation because transfection of siCCRK dramatically reduces the level phosphorylated CDK2 in GBM cells. Collectively, our data support the notion that CCRK is a CAK and is involved in glioblastoma carcinogenesis. CDK7 has been shown to play an important role in embryonic development in the chicken brain (Scholz et al., 2006), Drosophila (Leclerc et al., 2000; Merino et al., 2002), Xenopus (Fesquet et al, Oncogene 1997) and C. elegans (Wallenfang et al, 2002). Nevertheless, the role of the CCRK in embryonic development has not been deter mined. Our Northern blot analysis indicated that CCRK is predominant expressed in the brain and kidney, suggesting that it may involve in CNS or kidney formation. In this project, we propose to use the African clawed frog (Xenopus laevis) and zebrafish as our animal models to study the role of CCRK in embryogenesis. We choose Xenopus and Zebrafish as our animal models because: 1. They are structurally simple vertebrates which have well-defined developmental stages and easily identifiable blastomeres. 2. They have relatively short life cycles in which a fertilized egg takes only a couple of days to become a fully mature adult. 3. Their embryos can be cultured in vitro and hence the experimental condi tions can be easily controlled and precise genetic manipulations are possible. Compared to Xenopus, zebrafish offers several additional advantages: 1. It has an even shorter life cycle as compared to Xenopus. 2. It has a transparent body and therefore direct and continuou s inspection of diverse developmental processes like onconogenesis and angiogenesis is possible. 3. It can be easily maintained at large quantities in the laboratory environment. 4. Hundreds of fertilized eggs can be produced per mating pair per week, and the embryos are less sensitive to environmental changes. 5. Many zebrafish organs are similar to their human counterparts at anatomical, physiological and molecular levels. This is consistent with the fact that most human genes have orthologues in zebrafish (Gates et al., 1999). The objectives of this project are: 1. To clone the zebrafish ortholog of human CCRK. 2. To determine the spatial and temporal expression profiles of CCRK in Xenopus and zebrafish embryos. 3. To examine the phenotypes and investigate the function of CCRK by knocking down CCRK expression in Xenopus and zebrafish embryos. References: Fesquet D, Morin N, Doree M, Devault A. Oncogene. 1997;15:1303-7. Fisher RP, Morgan DO. Cell 1994;78:713–724. Gates MA, Kim L, Egan ES, Cardozo T, et al. Genome Res. 1999;9:334-47. Leclerc V, Raisin S, Léopold P. EMBO J. 2000;19:1567-75. Liu Y, Wu C, Galaktionov K. J Biol Chem 2004;279:4507–14. Merino C, Reynaud E, Vázquez M, Zurita M. Mol Biol Cell. 2002;13:3246 -56. Ng SS, Cheung YT, An XM, Chen YC, et al. J Natl Cancer Inst. 2007;99:936-48. Peng Y, Kwok KH, Yang PH, Ng SS, et al. Neuropharmacology. 2005;48:426-34. Peng Y, Jiang BH, Yang PH, Cao Z, et al. J Biol Chem. 2004a;279 :28509-14. Peng Y, Yang PH, Guo Y, Ng SS, et al. Invest Ophthalmol Vis Sci. 2004b;45:23-9. Peng Y, Yang PH, Ng SS, Lum CT et al. J Mol Biol. 2004c;340:819-27. Peng Y, Yang PH, Ng SS, Wong OG, et al.. Neurobiol Dis. 2004d;16:370-6. Poon RY, Yamashita K, Adamczewski JP, Hunt T et al. EMBO J 1993;12:3123–32. Scholz B, Kultima K, Mattsson A, Axelsson J, et al. BMC Neur osci. 2006;7:12. Solomon MJ, Harper JW, Shuttleworth J. EMBO J 1993;12:3133–42. Wallenfang MR, Seydoux G. Proc Natl Acad Sci U S A. 2002;99:5527-32. Wohlbold L, Larochelle S, Liao JC, Livshits G, et al. Cell Cycle 2006;5:546–54. |
| Project Title: | Development of Novel Second Generation Broad-spectrum hTERTC27-based Therapeutic Tumor Vaccine |
| Investigator(s): | Lin MC, Ng SM |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Support Programme (Tier 3) |
| Start Date: | 10/2008 |
| Completion Date: | 03/2010 |
| Abstract: |
| 1. To design novel hTERTC27-based tumor-specific super antigens (C27-SAgs) with both NK-cell activation and T-cell activation activities. 2. To construct recombinant adenovirus vectors encoding these C27-SAgs (Adv-C27-SAg) as tumor vaccines. 3. To screen by in vitro cell-based assays for the most efficient Ad v-C27-SAg that can activate the NK cells and T cells. 4. To demonstrate the superior anti-tumor effects of Adv-C27-SAg in vivo in immune-competent mouse xenograft models of hepatocellular carcinoma (HCC) and melanoma. 5. To apply for patent and to commercialize our Adv-C27-S Ag for cancer treatment. 6. To boost Hong Kong's reputation in biotechnology advancement through the development of our project and publications in high impact peer reviewed scientific journals. |
| Project Title: | Functional characterization of miR-200 family of microRNA in nasopharyngeal carcinom a |
| Investigator(s): | Lin MC, Ng SM |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 06/2009 |
| Abstract: |
| Nasopharyngeal carcinoma (NPC) is a malignancy arising from the epithelial cells lining the nasopharynx, which is mainly endemic in southern China and Southeast Asia including Guangdong and Hong Kong. Environmental factors, genetic susceptibility as well as Epstein-Barr virus (EBV) infection have been reported to be associ ated with the etiology of NPC [1]. However, the molecular basis of NPC pathogenesis has not been well defined. Although conventional therapies like surgery, radiotherapy, and chemotherapy can improve survival rates, NPC is still a highly fatal tumor as it can easily invade local tissues and metastasize to distant organs. Once metastasis occurs, the prognosis of patients is poor [2]. Therefore, it is important to develop new effect ive treatment approaches. MiRNAs are a novel class of endogenous, small non-protein coding RNA molecules, which are now recognized as crucial post-transcriptional regulators of gene expression. MiRNAs regulate their mRNA targets directly by cleavage or by repressing their translation, depending on the degree of complementariet y between the miRNAs and their target mRNAs. To date, more than 851 human miRNAs have been described in miRBase database (http://microrna.sanger.ac.uk) and it is predicted that the human genome encodes about 1000 miRNAs. Computati onal predictions of miRNA targets suggest that up to 30% of human protein coding genes may be regulated by miRNAs [3]. There is emerging evidence that miRNAs participate in a wide range of biological functions such as cellular proliferation, differentiation, cell cycle regulation and apoptosis. Therefore, miRNAs may also play an important role in various human diseases, including cancer [4]. Infection by EBV is common in NPC and EBV-encoded LMP1 is believed to be a key factor in NPC development. Our group has previously demonstrated that suppression of Epstein–Barr virus-encoded latent membrane protein -1 by RNA interference inhibits metastasis of nasopharyngeal cancer cells in vivo and in vitro [5, 6]. Recently, there have been several studies on EBV-encoded miRNAs [7-9], but not all NPC are EBV-positive. Therefore, the role of human miRNAs in NPC carcinogenesis urgently needs to be investigated. Recently, we have characterized the differentially expressed miRNA in glioma tissues from Chinese patients by miRNA microarray (unpublished data). We investigated the functions of several miRNAs (including miR-200a, miR-15b, miR-146b) which were significantly down-regulated in glioma samples. In particular, we discovered that miR-200a was significantly down-regulated in NPC C666-1 cells (Fig. 1). By loss of function and gain of function studies, we also sho wed that over-expression of miR-200a inhibited C666-1 cells growth, migration and invasion, while over-expression of miR-200a produced opposite results (Fig. 2). In this application, we will characterize the functions of miR-200a in NPC cells. As miRNAs are expressed in clusters, the functions of miRNAs belonging to this family (including miR-200-a, -b, -c, miR-429, and miR-141) will also be examined. The main objectives of the research proposal are: 1. To investigate the expression of miR-200 family in different NPC cell lines and tissues. 2. To predict the targets for miR-200 family by computation al approach. 3. To validate the potential miRNA targets by dual luciferase assays. References: 1. Hildesheim, A. and P.H. Levine, Etiology of Nasopharyngeal Carcinoma: A Review. Epidemiol Rev, 1993. 15(2): p. 466-485. 2. Li, X.-P., et al., Inhibition of human nasopharyngea l carcinoma growth and metastasis in mice by adenovirus-associated virus-mediated expression of human endostatin. Mol Cancer Ther, 2006. 5(5): p. 1290-1298. 3. Sassen, S., E.A. Miska, and C. Caldas, MicroRNA—implications for cancer. Virchows Archiv, 2008. 452(1): p. 1-10. 4. Esquela-Kerscher, A. and F.J. Slack, Oncomirs—microRNA s with a role in cancer. Nat Rev Cancer, 2006. 6(4): p. 259-69. 5. LI, X., et al., Recombinant adeno-associated virus mediated RNA interference inhibits metastasis of nasopharyngeal cancer cells in vivo and in vitro by suppression of Epstein-Barr virus encoded LMP-1. International journal of oncology, 2006. 29(3): p. 595-603. 6. Li, X., et al., Suppression of Epstein–Barr virus-encoded latent membrane protein-1 by RNA interferen ce inhibits the metastatic potential of nasopharyngeal carcinoma cells. Biochemical and Biophysical Research Communications, 2004. 315(1): p. 212-218. 7. Lo, A.K.F., et al., Modulation of LMP1 protein expression by EBV-encoded microRNAs. Proceedings of the National Academy of Sci ences, 2007. 104(41): p. 16164-16169. 8. Choy, E.Y.-W., et al., An Epstein-Barr virus-encoded microRNA targets PUMA to promote host cell survival. J. Exp. Med., 2008: p. jem.20072581. 9. Sengupta, S., et al., MicroRNA 29c is down-regulated in nasopharyngeal carcinomas, up-regulating mRNAs encoding extracellular matrix proteins. Proceedings of the National Academy of Sciences, 2008. 105(15): p. 5874-5878. |
| Project Title: | Development of Novel Nanopolymers for Cancer Gene Therapy |
| Investigator(s): | Lin MC, Sun H, Ng SM |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Support Programme (Tier 3) |
| Start Date: | 12/2009 |
| Abstract: |
| Efficiency and safety of gene delivery vectors are prime concerns for gene therapy. Compared with recombinant viruses, non-viral vectors like nanopolymers are generally safer and more amenable to chemical modifications. Our laboratory has recently synthesized a new nanopoly mer, which consists of low molecular weight polyethyleneimine, beta-cyclodextrin, and folic acid (PEI600-CyD-FA) (H1). Our preliminary data showed that H1 exhibits high transfecti on efficiency comparable to that of adenovirus and the leading transfection reagents available in the market. The purpose of this research is to further characterize the efficiency and biosafety of H1 in vitro and in an established tumor model in mice. The specific objectives of this project are: 1. To optimize and standardize the synthesis procedure of H1. 2. To evaluate the therapeutic efficacy of H1 / plasmid expressing interleukin 2 (pIL2) for the treament of melanoma in vivo in mice. 3. To evaluate the efficacy of H1 / plasmid expressing an anti-angiogenesis peptide, Kringle 1 domain of Hepa tocyte Growth Factor (HGFK1), for the treatment of hepatocellular carcinoma (HCC). 4. To develop a platform technology to generate other new nanopolymers formed by the conjugat ion of PEI600-CyD with betaine or HIV-TAT peptides. |
| List of Research Outputs |
| An X. , Ng S.M. , Xie D., Zeng Y.X., Sze J. , Wang J. , Chen Y.C., Chow B.K.C. , Lu G., Poon W.S., Kung H.F., Wong B.C.Y. and Lin M.C. , Functional characterisation of cell cycle-related kinas e (CCRK) in colorectal cancer carcinogenesis. , European Journal of Cancer . 2010, 46: 1752-1761. |
| Cheung K.C. , Yang P. , Huang Q.H., Chen Z., Chen S.J., Lin M.C. and Kung H.F., Identification of Protein Domains Required for Makorin-2-me diated Neurogenesis Inhibition in Xenopus Embryos, Biochemical and Biophysical Research Communicatio ns . 2010, 394(1): 18-23. |
| Deng R., Yue Y., Jin F., Chen Y.C., Kung H.F., Lin M.C. and Wu C., Revisit the Complexation of PEI And DNA - How to Make Low Cytotoxic and High Efficient PEI Gene Transfecti on Non-viral Vectors with a Controllable Chain Length and Structure?, Journal of Controlled Release . 2009, 140(1): 40-46. |
| Dong Q., Liu Z., Chen Y., Chan C.Y., Lin M.C. , Kung H.F., Chan H.L., Sung J.J. and He M.L., High Level Virion Production and Surface Antigen Expressi on with 1.5 Copies of Hepatitis B Viral Genome, Journal of Virological Methods . 2009, 159(2): 135-140. |
| Li G., Zhang X.A., Zhang J.F., Chan C.Y., Yew D.T., He M.L., Lin M.C. , Leung P.C. and Kung H.F., Ethanol Extract of Fructus Ligustri Lucidi Promotes Osteogenesis of Mesenchymal Stem Cells, Phytotherapy Research . 2009, 24(4): 571-576. |
| Li M. , Wang J. , Ng S.M. , Chan C.Y., He M.L., Yu F. , Lai L., Shi C. , Chen Y.C., Yew D.T., Kung H.F. and Lin M.C. , Adenosine Diphosphate-ribosylation Factor 6 is Required for Epidermal Growth Factor-induced Glioblastoma Cell Proliferation, Cancer . 2009, 115(21): 4959-4972. |
| Liang B., He M.L., Chan C.Y., Chen Y.C., Li X.P., Li Y., Zheng D., Lin M.C. , Kung H.F., Shuai X.T. and Peng Y., The Use of Folate-PEG-grafted-hybranched-PEI Nonviral Vector for the Inhibition of Glioma Growth in the Rat, Biomaterials . 2009, 23-24: 4014-4020. |
| Lin M.C. , Yu F. , Ng S.M. and Kung H.F., Knocking Down Interferon Induced Transmembrane Protein 1 (IFITM1) Inhibited Cell Proliferation and Invasion in Glioma Cells, Experimental Biology 2010; April 24-28, 2010; Anaheim, California, USA . 2010. |
| Tu S.P., Sun R.W.Y. , Lin M.C. , Cui J.T., Zou B. , Gu Q. , Kung H.F., Che C.M. and Wong B.C.Y. , Gold (III) Porphyrin Complexes Induce Apoptosis and Cell Cycle Arrest and Inhibit Tumor Growth in Colon Cancer, Cancer . 2009, 115(19): 4459-4469. |
| Tu S.P., Sun Y.W., Cui J.T., Zou B. , Lin M.C. , Gu Q. , Jiang S.H., Kung H.F., Korneluk R.G. and Wong B.C.Y. , Tumor Suppressor XIAP-associated Factor 1 (XAF1) Cooperates with Tumor Necrosis Factor-related Apoptosis-inducing Ligand to Suppress Colon Cancer Growth and Trigger Tumor Regression, Cancer . 2010, 116(5): 1252-1263. |
| Wu G.Q., Xie D., Yang G.F., Liao Y.J., Mai S.J., Deng H.X., Sze J. , Guan X.Y., Zeng Y.X., Lin M.C. and Kung H.F., Cell Cycle-Related Kinase Supports Ovarian Carcinoma Cell Proliferation via Regulation of Cyclin D1 and is a Predictor of Outcome in Ovarian Carcinoma Patients, International Journal of Cancer . 2009, 125(11): 2631-42. |
| Xia H. , Ng S.M. , Kung H.F. and Lin M.C. , Inhibitory Effects of miR-200a on Nasopharyngeal Carcinoma Cell Growth, Migration and Invasion are Mediated by Different Targets, ASCB 49th Annual Meeting - December 5-9, 2009, San Diego, CA, USA. . 2009, 421. |
| Xia H. , Ng S.M. , Jiang S.S., Cheung K.C. , Sze J. , Bian X.W., Kung H.F. and Lin M.C. , miR-200a-mediated Downregulation of ZEB2 and CTNNB1 Differentially Inhibits Nasopharyngeal Carcinoma Cell Growth, Migration and Invasion, Biochemical and Biophysical Research Communications . 2009, 391(1): 535-541. |
| Xu Z. , Ng S.M. and Lin M.C. , Cell Cycle-Related Kinase Phosphorylates Casein Kinase Beta in Glioblasoma Cells, ASCB 49th Annual Meeting; December 5-9, 2009, San Diego, CA, USA. . 2009, 1017. |
| Yao H. , Ng S.M. , Li M. and Lin M.C. , An Effective Interleukin-2 Cancer Immunotherapy Deliver ed by a Novel Polymeric nanoparticle in Melanoma, Annual Meeting of the International Society for Biological Therapy of Cancer; 28-31 October, 2009; Washington, USA . 2009. |
| Yao H. , Ng S.M. , Tang G. , Kung H.F. and Lin M.C. , Development of a Low-toxicity and High-efficiency Polymeric Nanoparticle for Gene Delivery, 2009 International Society for Cell & Gene Therapy of Cancer; Cork, Ireland; 2-4 September, 2009. . 2009. |
| Yao H. , Ng S.M. , Tucker W.O. , Tsang Y.K.T. , Man K. , Wang X.M., Chow B.K.C. , Kung H.F., Tang G. and Lin M.C. , The gene transfection efficiency of a folate-PEI600-cyclodextrin nanopolymer, Biomaterials . 2009, 30(29): 5793-5803. |
| Yu F. , Ng S.M. , Lum C.T. , Cheung K.C. , An X.M. and Lin M.C. , Functional Characterization of Interferon Induced Transmembrane Protein 1 (IFITM1) in Colorectal Carcinogenesis, 34th FEBS Congress: Life's Molecular Interactions; Prague, Czech Republic, 4-9, July, 2009. (P4-140, Published in the FEBS Journal) . 2009, 276 (s1): 134. |
| Zhang J.F., Li G., Chan C.Y., Meng C.L., Lin M.C. , Chen Y.C., He M.L., Leung P.C. and Kung H.F., Flavonoids of Herba Epimedii Regulate Osteogenesis of Human Mesenchymal Stem Cells Through BMP and Wnt/β-catenin Signaling Pathway, Molecular and Cellular Endocrinology . 2009, 314(1): 70-74. |
| Zheng B. , Sze J. , Cheung K.C. , Lin M.C. and Kung H.F., Super Interferons for the Treatment of Bird Flu, Tri-Society Annual Conference 2009 of the Society for Leukocyte Biology, International Cytokine Society, & International Society for Interferon and Cytokine Research; Portugal; 17-21 October, 2009. . 2009. |
| Zhu X., Li D.P., Fan W.G., Lin M.C. , Wang J.L., Lin S.Q., Huang J.Q. and Kung H.F., Lack of association between the GRP78 polymorphisms in the promoter and 3' UTR and susceptibility to chronic HBV infection in a Chinese Han population, BMC Medical Genetics . 2010, 11: 83. |
| Zhu X., Chen M., Tian L., Li D., Xu P., Lin M.C. , Xie D. and Kung H.F., Single Nucleotide Polymorphism of Rrs430397 in the Fifth Intron of GRP78 gene and Clinical Relevance of Primary Hepatocellular Carcinoma in Han Chinese: Risk and Prognosis., International Journal of Cancer . 2009, 125(6): 1352-1357. |
| Researcher : Liu LL |
| List of Research Outputs |
| Shi B., Merten S., Wong D.K.Y., Chu C.K. , Liu L.L. , Lam S.K. , J ä ger A., Wong W.T. , Chiu P. and Metz P., The Rhodium-Catalyzed Carbene Cyclization Cycloaddition Cascade Reaction of Vinylsulfonates, Advanced Synthesis and Catalysis . 2009, 351: 3128-3132. |
| Researcher : Liu P |
| List of Research Outputs |
| Liu P. , Zhou C. , Xiang S. and Che C.M. , Highly Efficient Oxidative Carbon-carbon Coupling with SBA-15-support Iron Terpyridine Catalyst, Chemical Communications . 2010, 46: 2739-2741. |
| Liu P. , Oxidation and Nitrene Transfer Reactions Catalyzed by Iron-Oligopyridine Complexes (PhD Thesis) . 2009. |
| Researcher : Liu X |
| List of Research Outputs |
| Liu X. , Gold(I) and Platinum(II)-Catalyzed Hydroamination of Alkenes and Alkynes and Related Tandem Reactions for Synthesis of Nitrogen-Containing Multi-Cyclic Ring Compounds and Chiral Amines (PhD Thesis) . 2010. |
| Liu X. , Li C.Y. and Yang D. , Total Synthesis of Fumagillol, The 239th American Chemical Society National Meeting, San Francisco, U.S.A., March 1, 2010 . |
| Liu X. and Che C.M. , Highly Enantioselective Synthesis of Chiral Secondary Amines by Gold(I)/ Chiral Brønsted Acid Catalyzed Tandem Intermolecular Hydroamination and Transfer Hydrogenation Reactions , Organic Letters . 2009, 11: 4204-4207. |
| Researcher : Liu X |
| List of Research Outputs |
| Liu X. , Gold(I) and Platinum(II)-Catalyzed Hydroamination of Alkenes and Alkynes and Related Tandem Reactions for Synthesis of Nitrogen-Containing Multi-Cyclic Ring Compounds and Chiral Amines (PhD Thesis) . 2010. |
| Liu X. , Li C.Y. and Yang D. , Total Synthesis of Fumagillol, The 239th American Chemical Society National Meeting, San Francisco, U.S.A., March 1, 2010 . |
| Liu X. and Che C.M. , Highly Enantioselective Synthesis of Chiral Secondary Amines by Gold(I)/ Chiral Brønsted Acid Catalyzed Tandem Intermolecular Hydroamination and Transfer Hydrogenation Reactions , Organic Letters . 2009, 11: 4204-4207. |
| Researcher : Liu Y |
| List of Research Outputs |
| Liu Y. , Lok C.N. , Ko C.B. , Shum Y.T. , Wong M.K. and Che C.M. , Subcellular Localization of a Fluorescent Artemisinin Derivative to Endoplasmic Reticulum, Organic Letters . 2010, 12: 1420-1423. |
| So M.H. , Ho C.M. , Liu Y. and Che C.M. , Aerobic oxidation of benzylic amines to imines catalyzed by graphite-supported gold nanoparticles, Eleventh tetrahedron symopsium . 2010. |
| So M.H. , Liu Y. , Ho C.M. and Che C.M. , Graphite-Supported Gold Nanoparticles as Efficient Catalyst for Aerobic Oxidation of Benzylic Amines to Imines and N-Substituted 1,2,3,4-Tetrahydroisoquinolin es to Amides: Synthetic Applications and Mechanistic Study, Chemistry - An Asian Journal . 2009, 4: 1551-1561. |
| Researcher : Lo KC |
| List of Research Outputs |
| Lo K.C. , Zhu G. and Sze K.H. , Study on the Interaction between DNA-binding Domain (DBD) of Human Androgen Receptor (AR) and SWIRM Domain of Lysine-specific Demethylase 1 (LSD1), Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic Universit y, Hong Kong, April 24, 2010. . 2010, O-97. |
| Researcher : Lo KY |
| List of Research Outputs |
| Lo K.Y. , Zhou C. , Wong M.K. and Che C.M. , Silver(I)-mediated Highly Enantioselective Synthesis of Axially Chiral Allenes Under Thermal and Microwave-assisted Conditions; The Best Poster Presentation for Organic Chemistry, The 15th Symposium on Chemistry Postgraduate Research in Hong Kong . 2010. |
| Lo K.Y. , Zhou C. , Wong M.K. and Che C.M. , Silver(I)-mediated Highly Enantioselective Synthesis of Axially Chiral Allenes Under Thermal and Microwave-assisted Conditions, Chemical Communications . 2010, 46: 213-215. |
| Yang D. , Yip P.K.T. , Yang M., He W. , Chen H. , Song K. and Lo K.Y. , Stereoselective Cyclization Reactions through Palladium and Silver Catalysis, The 6th Asian-European Symposium on Metal Mediated Efficient Reactions, Singapore, June 1, 2010 . 2010. |
| Researcher : Lo KY |
| List of Research Outputs |
| Lo K.Y. , Zhou C. , Wong M.K. and Che C.M. , Silver(I)-mediated Highly Enantioselective Synthesis of Axially Chiral Allenes Under Thermal and Microwave-assisted Conditions; The Best Poster Presentation for Organic Chemistry, The 15th Symposium on Chemistry Postgraduate Research in Hong Kong . 2010. |
| Lo K.Y. , Zhou C. , Wong M.K. and Che C.M. , Silver(I)-mediated Highly Enantioselective Synthesis of Axially Chiral Allenes Under Thermal and Microwave-assisted Conditions, Chemical Communications . 2010, 46: 213-215. |
| Yang D. , Yip P.K.T. , Yang M., He W. , Chen H. , Song K. and Lo K.Y. , Stereoselective Cyclization Reactions through Palladium and Silver Catalysis, The 6th Asian-European Symposium on Metal Mediated Efficient Reactions, Singapore, June 1, 2010 . 2010. |
| Researcher : Lok CN |
| Project Title: | Subcellular and redox targets of some synthetic and natural anticancer compounds |
| Investigator(s): | Lok CN, Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 10/2008 |
| Completion Date: | 03/2010 |
| Abstract: |
| The purpose of the proposed project: To determine the mechanisms of action of novel synthetic anticancer compounds in terms of several compelling subcellular (nuclear, mitochondrial and lysosomal) and redox (thiol) targets. Key issues and problems being addressed: Drug discovery and synthetic chemistry endeavors in our research group have yielded a number of bioactive compounds (reviewed in reference 1). The further development of these agents toward successful application in biotechnolog y and medicine requires determination of the mechanisms of action of the compounds with the ultimate goal to identify the molecular targets with which the compounds interact. Establishment of experimental systems to facilitate the determination of direct drug actions is essential. We will develop a panel of assays to investigate the subcellular and redox targets of several synthetic metal based compounds (gold and platinum) and pure chinese herbal medicinal compounds (saponins). Reference: 1. Sun, R. W.; Ma, D. L.; Wong, E. L.; Che, C. M., Some uses of transition metal complexes as anti-cancer and anti-HIV agents. Dalton Trans 2007, (43), 4884-92. |
| List of Research Outputs |
| Ho C.M. , Yau K.W. , Lok C.N. , So M.H. and Che C.M. , Oxidative Dissolution of Silver Nanoparticles by Biologically Relevant Oxidants. A kinetic and Mechanistic Study, 17th Symposium of Chemistry Postgraduate Research in Hong Kong . 2010. |
| Ho C.M. , Yau K.W. , Lok C.N. , So M.H. and Che C.M. , Oxidative Dissolution of Silver Nanoparticles by Biologically Relevant Oxidants: A Kinetic and Mechanistic Study, Chemistry - An Asian Journal . 2010, 5: 285-293. |
| Lai S.W. , Liu Y., Zhang D., Wang B. , Lok C.N. , Che C.M. and Selke M., Photoluminescent Properties and Singlet Oxygen Production of Cyclometalated Platinum(II) Complexes bearing Upper-rim Phosphinated Calix[4]arenes, The Fifth International Symposium on Macrocyclic and Supramolecular Chemistry, Nara Prefecture, Japan, 6-10 June . 2010. |
| Liu Y. , Lok C.N. , Ko C.B. , Shum Y.T. , Wong M.K. and Che C.M. , Subcellular Localization of a Fluorescent Artemisinin Derivative to Endoplasmic Reticulum, Organic Letters . 2010, 12: 1420-1423. |
| Sun R.W.Y. , Li C.K.L. , Ma D.L. , Yan J. , Lok C.N. , Leung C.H. , Zhu N. and Che C.M. , Stable anticancer gold(III)-porphyrin complexes: effects of porphyrin structure, Chemistry - A European Journal . 2010, 16: 3097-3113. |
| Researcher : Low KH |
| List of Research Outputs |
| Chui S.Y. , Low K.H. , Roy V.A.L. and Che C.M. , Homoleptic Metal Organothiolate and Organoacetylide Coordination Polymers: Structural Determination using Powder X-ray diffraction and Their Materials Properties, AsCA'09 Beijing Joint Conference of the Asian Crystallographic Association and Chinese Crystallographic Society . 2009. |
| Low K.H. , Li C.H., Roy V.A.L., Chui S.Y. , Chan L.F. and Che C.M. , Homoleptic copper(I) phenylselenolate polymer as a single-source precursor for Cu2Se nanocrystals. Structu re, photoluminescence and application in field-effect transistor, In: David MacMillan , Chemical Science . The Royal Society of Chemistry, 2010, 1: 515-518. |
| Low K.H. , Synthesis, Structural Characterization and Application s of Homoleptic Organosulfur and Organoselenium Metal Polymers (PhD Thesis) . 2010. |
| Researcher : Low KH |
| List of Research Outputs |
| Chui S.Y. , Low K.H. , Roy V.A.L. and Che C.M. , Homoleptic Metal Organothiolate and Organoacetylide Coordination Polymers: Structural Determination usin g Powder X-ray diffraction and Their Materials Properties, AsCA'09 Beijing Joint Conference of the Asian Crystallographic Association and Chinese Crystallographic Society . 2009. |
| Low K.H. , Li C.H., Roy V.A.L., Chui S.Y. , Chan L.F. and Che C.M. , Homoleptic copper(I) phenylselenolate polymer as a single-source precursor for Cu2Se nanocrystals. Structure, photoluminescence and application in field-effect tr ansistor, In: David MacMillan , Chemical Science . The Royal Society of Chemistry, 2010, 1: 515-518. |
| Low K.H. , Synthesis, Structural Characterization and Applications of Homoleptic Organosulfur and Organoselenium Metal Polymers (PhD Thesis) . 2010. |
| Researcher : Lu J |
| List of Research Outputs |
| But Y.S. , Lu J. and Toy P.H. , Organocatalytic Mitsunobu Reactions Using 3,5-Dinitrobenzoic Acid, Synlett . 2010, 21: 1115-1117. |
| Researcher : Lu W |
| Project Title: | Nanostructures and Mesophases Self- Assembled from Ionic Transition Metal Complexes with Oleophilic Counterions |
| Investigator(s): | Lu W, Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 01/2010 |
| Abstract: |
| The objective of the present project is to develop novel nanostructured materials and mesophases from ionic transition metal complexes through a counterion-controlling approach. While nanostructured materials and mesophases based on organic small molecules have been rich in the literature and stepped into large-scale production and found numerous applications in high-tech industries, the functional materials derived from organometallic and coordination complexes are in their infancy. Nanomaterials self-assembled from transition metal complexes combi ne the merits of both organic and inorganic materials. The salient advantage of organometallic or metal organic nanomaterials over their more classical inorganic counterparts is that their constituents, the building blocks, are molecular or clusters that can be designed and ration ally synthesized, that is, we can produce nanomaterials with predetermined physical properties and these properties can be systematically tuned by harnessing the power of chemical modifications at the molecular level. Importantly, functional materials derived from organometallic and coordination complexes, due to their various metal coordination geometries, can be readily engineered with phosphorescent, magnetic and redox-active properties, which are not easily accessed with nanomaterials derived from organic molecules. However, lots of transition metal complexes with material merits are ionic in nature . The presence of small counterions, in one hand, confer the complexes intrinsic ion-conductivities, and in the other hand, prevent them from standard processing usually used for neutral organic compounds. We now aim to develop a novel approach for processing nanomaterials and mesophases based on ionic transition metal complexes using highly oleophilic counterions. The introductio n of highly oleophilic counterions into organometallic and coordination complexes have three major advantages. First, the coordination environment around the transition metal complexes will not be altered, and therefore the functional properties of the complexes are kept. Second, the highly oleophilic counterions will render these ionic transition metal complexes soluble in nonpol ar solvents, such as alkanes, cycloalkanes and benzene. Nano-sized aggregates are anticipated to be formed by the ionic part of the transition metal complexes, which allows the study of the properties of these nano-aggregates in inert solvents. Note that this is an unprecedented target for coordination chemistry. Third, mesophases (both thermotropic and lyotropic liquid crystals) can be anticipated for these transition metal complexes with highly oleophilic counterions. This is a so-called ionic self-assembly (ISA) approach leading to liquid crystals. The current project aims to establish a general method to introduce highly oleophilic counterions to ionic organometallic and coordination complexes and to study their photophysical, liquid-crystalline and nanostructure-forming properties. We also aim to develop solution-processible devices with these nano structures or mesophases as optoelectronically active materials The current project is a new direction for researches in transition metal complexes, hence the present project is to add further credits to the leading position of HKU in the field of inorganic chemistry. Specifically, it is the goal of the project to develop: 1) Synthetic methodology for ionic transition metal complexes with oleophilic counterions The project aims to explore which types of oleophilic counterions can be introduced into ionic transition metal complexes and render them soluble in nonpolar solvents. The project also aims to develop, from above-mentioned ionic transition metal complexes with oleophilic counterions, self-assembled morphology (superstructures with possible wire-, tube- or sheet-like shapes) in the nanometer or submicron ( <1 μm) scales. The long-range order of these nano- and submicron-structures will be a key issue in the morphological studies for identifying them from other soft-matters of organic polymers and crystallized inorga nic nanostructures. 2) Dynamics and kinetics of the self-assembly of ionic transition metal complexes with oleophilic counterions The project aims to probe how these nanostructures and mesophases are formed from molecular-level ionic transition metal complexes. The dynamics and kinetics of the aggregation nucleus in self-assembly will be addressed, and thus provide a hint for further development of this type of aggregation processes. The role of metal-metal, ligand-ligand, counterion-counterion interactions as the driving force for anisotropic growth of nanostructures will be evaluated. 3) Potential applications of these nanostructures and mesophases Ionic transition metal complexes are well known functional materials with phosphorescent, magnetic, redox-active or semiconducting properties and these properties are anticipated to be kept in the nanostructures and mesophases derived from the ionic transition metal complexes with oleophilic counterions. Solution-processable protocols will be developed to fabricate optoelectronic devices using these nanostructures and mesophases as active materials. |
| Project Title: | 5th International Symposium on Macrocyclic & Supramolecular Chemistry Supramolecular Polyelectrolytes and Chromonic Mesophases Self-Organized from Phosphorescent Cationic Organoplatinum(II) Complex es in Water |
| Investigator(s): | Lu W |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 06/2010 |
| Completion Date: | 06/2010 |
| Abstract: |
| N/A |
| List of Research Outputs |
| Chen Y. , Li K. , Lu W. , Chui S.Y. , Ma C.W. and Che C.M. , Photoresponsive Supramolecular Organometallic Nanosheets Induced by Pt II -- Pt II and C---H ... p Interactions, Angewandte Chemie Internationa l Edition . 2009, 48: 9909 –9913. |
| Lu W. , Chen Y. , Roy V.A.L., Chui S.Y. and Che C.M. , Supramolecular Polymers and Chromonic Mesophases Self -Organized from Phosphorescent Cationic Organoplatinum(II) Complexes in Water , Angewandte Chemie International Edition . 2009, 48: 7621-7625. |
| Tang H.W. , Lu W. , Che C.M. and Ng K.M. , Double Imaging of Latent Fingerprints by Gold Nanopart icles-Assisted Imaging Mass Spectrometry , The 1st Asian & Oceanic Mass Spectrometry Conference, at Tsukuba International Congress Center, Tsukuba, Japan . 2010. |
| Tang H.W. , Lu W. , Che C.M. and Ng K.M. , Gold Nanoparticles and Imaging Mass Spectrometry: Double Imaging of Latent Fingerprints, Analytical Chemistry . 2010, 82: 1589–1593. |
| Researcher : Lui KO |
| List of Research Outputs |
| Lui K.O. and Chan W.T. , Single Particle Analysis using Time-resolved ICP-MS, Colloquium Spectroscopicum Internationale XXXVI, Budapest, Hungary, August 30 - September 3, 2009 (Oral presentation) . 2009. |
| Yeung S.L. , Cheng C.W., Lui K.O. , Tsang J.S.H. , Chan W.T. and Lim B.L. , Purple acid phosphatase-like sequences in prokaryotic genomes and the characterization of an atypical purple alkaline phosphatase from Burkholderia cenocepacia J2315, Gene . 2009, 440: 1-8. |
| Researcher : Lum CT |
| Project Title: | Identification of chemotherapeutic drugs targeting cancer stem cells and the micro RNAs regulated by the drugs |
| Investigator(s): | Lum CT, Lin MC, Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 12/2009 |
| Abstract: |
| Cancer stem cells (CSCs) are a subset of cancer cells that pose the ability to self-renew and differ entiate, and can give rise to all cell types found in cancer. They are responsible for tumor maintenance as well as spreading, and are thus targets for cancer therapy. However, evidence suggested that CSCs are resistant to chemotherapy and radiotherapy [1], as most conventional chemotherapies kill only differentiating and differen tiated cells which comprise the bulk of tumors [2], leaving behind CSCs which can give rise to new tumors. It is thus of vital importance to develop therapeutic agents capable of killing CSCs. A series of gold(III) compounds which posed anti-tumor activities were synthesized by the research group led by Prof. Chi-Ming Che, Dep artment of Chemistry, the University of Hong Kong [3]. One of them, gold(III) meso-tetraphenylporphyrin 1a (gold-1a), has been shown to be effective in prolonging the survival of hepatocellular carcinoma-bearing rats [4] and melan oma-bearing mice (unpublished data), inhibited tumor growth in nasopharyngeal carcinoma-bearing mice [5] and colon cancer-bearing mice [6], induced apoptosis [4] and inhibited angiogenesis (unpublished data). We therefore hypothesize that gold-1a may exhibit its anti-tumor activity by targeting CSCs. CD133 is currently the most widely proposed CSC marker. In a large variety of malignancies, including melanoma [7], colorectal cancer [8], hepatocellular carcinoma [9] and brain tumor [10,11], the expression of CD133 was upregulated. Moreover, CD133+ cells in a tumor cell population were more tumorigenic than the CD133- cells [9]. Our preliminary data showed that gold-1a didn’t enrich the percentage of CD133+ cells after having treated B16-F1 mouse melanoma cells, indicating that the compound was equally effec tive in killing tumor cells as well as CSCs. In contrast, our data indicated that cisplatin, a conventional chemotherapeutic drug used in various human cancers, enriched CD133+ cells in B16-F1. Micro RNAs (miRNAs) are non-coding single-stranded RNAs of 21-23 nucleotides long. Their main function is to negatively regulate gene expression. Several miRNAs have been linked to CSCs, including miR-200 and let-7 families [12]. In this study, we aim to identify the miRNAs involved in stem cell self renewal which are regulated by the chemotherapeutic drugs used in this study. It is of vital importance to fully understand the mechanisms through which gold-1a and other chemotherapeutic drugs exert their anti-cance r effects and the miRNAs they regulate. In fact, our preliminary data showed that gold-1a upregulated miR-122, which inhibited tube formation in vitro, in a time-dependent manner. The objectives of this project are, first, to evaluate the cytotoxic effects of gold-1a and oth er chemotherapeutic drugs on CSCs. We will use B16-F1 mouse melanoma cell line as a model as we have already demonstrated that gold-1a prolonged the survival and inhibited tumor growth of B16-F1-induced melanoma bearing mice. Second, to investigate the stem cell-related miRNA expression profile in B16-F1 melanoma cells in response to gold-1a and other chemotherapeutic drugs. The specific aims are: 1. To determine the cytotoxic effects of gold-1a and other chemotherapeutic drugs on CSCs. 2. To identify the miRNAs known to be involved in stem cell self-renewal which are differentially expressed in response to gold-1a and other chemotherapeutic drugs. Reference 1. Bednar F, Simeone DM. Pancreatic cancer stem cells and relevance to cancer treatments. J Cell Biochem 2009;107(1):40-5. 2. Gangemi R, Paleari L, Orengo AM, Cesario A, Chessa L, Ferrini S, Russo P. Cancer stem cells: a new paradigm for understanding tumor growth and progression and drug resistance. Curr Med Chem. 2009;16(14):1688-703. 3. Che CM, Sun RW, Yu WY, Ko CB, Zhu N, Sun H. Gold(III) porphyrins as a new class of anticancer drugs: cytotoxicity, DNA binding and induction of apoptosis in human cervix epitheloid cancer cells. Chem Commun (Camb). 2003;14:1718-9. 4. Lum CT, Yang ZF, Li HY, Sun RW, Fan ST, Poon RT, Lin MC, Che CM, Kung HF. Gold(III) compound is a novel chemo-cytotoxic agent for hepatocellular carcinoma (HCC). Int J Cancer 2006;118(6):1527-38. 5. To YF, Sun RW, Chen Y, Chan VS, Yu WY, Tam PK, Che CM, Lin CL. Gold(III) porphyrin complex is more potent than cisplatin in inhibiting growth of nasopharyngeal carcinoma in vitro and in vivo. Int J Cancer 2009;124(8):1971-9. 6. Tu S, Sun RW, Lin MC, Cui JT, Zou B, Gu Q, Kung HF, Che CM, Wong BC. Gold(III) porphyrin complexes induce apoptosis and cell cycle arrest and inhibit tumor growth in colon cancer. Cancer. 2009. In press. 7. Rappa G, Fodstad O, Lorico A. The stem cell-associated antigen CD133 (Prominin-1) is a molecular therapeutic target for metastatic melanoma. Stem Cells 2008;26(12):3008-17. 8. Dallas NA, Xia L, Fan F, Gray MJ, Gaur P, van Buren G 2nd, Samuel S, Kim MP, Lim SJ, Ellis LM. Chemoresistant colorectal cancer cells, the cancer stem cell phenotype, and increased sensitivity to insulin-like growth factor-I receptor inhibition. Cancer Res 2009;69(5):1951-7. 9. Ma S, Chan KW, Hu L, Lee TK, Wo JY, Ng IO, Zheng BJ, Guan XY. Identification and characterization of tumorigenic liver cancer stem/progenitor cells. Gastroenterology 2007;132(7):2542-56. 10. Chiou SH, Kao CL, Chen YW, Chien CS, Hung SC, Lo JF, Chen YJ, Ku HH, Hsu MT, Wong TT. Identification of CD133-positive radioresistant cells in atypical teratoid/rhabdoid tumor. PLos ONE 2008;3(5):e2090. 11. Liu G, Yuan X, Zeng Z, Tunici P, Ng H, Abdulkadir IR, Lu L, Irvin D, Black KL, Yu JS. Analysis of gene expression and chemoresistance of CD133+ cancer stem cells in glioblastoma. Mol Cancer 2006;5:67. 12. Peter ME. Let-7 and miR-200 microRNAs: guardians against pluripotency and cancer progression. Cell Cycle. 2009;8(6):843-52. |
| List of Research Outputs |
| Yu F. , Ng S.M. , Lum C.T. , Cheung K.C. , An X.M. and Lin M.C. , Functional Characterization of Interferon Induced Transme mbrane Protein 1 (IFITM1) in Colorectal Carcinogenesis, 34th FEBS Congress: Life's Molecular Interactions; Prague, Czech Republic, 4-9, July, 2009. (P4-140, Published in the FEBS Journal) . 2009, 276 (s1): 134. |
| Researcher : Ma C |
| List of Research Outputs |
| Cao Q., Guan X. , George M.W., Phillips D.L. , Ma C. , Kwok W.M., Li M. , Du Y. , Sun X.Z. and Xue J. , Ultrafast Time-resolved Transient Infrared and Resonance Raman Spectroscopic Study of the Photo-deprotection and Rearrangement Reactions of p -Hydroxyphenacyl Caged Phosphates, Faraday Discuss . 2010, 145: 171-183. |
| El-Khoury P.Z., Kwok W.M., Guan X. , Ma C. , Phillips D.L. and Tarnovsky A.N., Photochemistry of Iodoform in Methanol: Formation and Fate of the Iso -CHl 2 -I Photoproduct , ChemPhysChem . 2009, 10: 1895-1900. |
| Kwok W.M., Ma C. and Phillips D.L. , Bright” and “Dark” Excited States of an Alternating AT Oligomer Characterized by Femtosecond Broadband Spectroscopy, Journal of Physical Chemistry B . 2009, 113: 11527-11534. |
| Ma C. , Kwok W.M., An H. , Guan X. , Fu Y. , Toy P.H. and Phillips D.L. , A Time-Resolved Spectroscopic Study of the Bichromophoric Phototrigger 3', 5'-Dimethoxybenzoin Diethyl Phosphate: Interaction Between the Two Chromophores Determines the Reaction Pathway, Chemistry - A European Journal . 2010, 16: 5102-5118. |
| Ma C. , Kwok W.M., An H. , Du Y. , Toy P.H. and Phillips D.L. , Femtosecond Transient Absorption and Nanosecond Time-resolved Resonance Raman Study of Photo-deprotection Reactions of Benzoin Caged Phototriggers , Femtochemistry IX: Femtochemistry, Femtobiology, and Femtophysics -- Frontries in Ultrafast Science and Technology, Beijing, China, August 8-13, 2009 . P-43: 111. |
| Ma C. , Kwok W.M. , Chan W.S. , Du Y. , Zuo P. , Kan T.W. , Toy P.H. and Phillips D.L. , Time-Resolved Spectroscopy Studies of the Photodeprotection Reactions of p -Hydroxyphenacyl Ester Phototrigger Compounds, Current Science . 2009, 97: 202-209. |
| Ma C. , Kwok W.M., An H. , Fu Y. , Toy P.H. and Phillips D.L. , Time-resolved Spectroscopy Studies of the Bichromophoric Phototrigger 3', 5'-dimethoxybenzoin Diethyl Phospate, The 2nd Asian Spectroscopy Conference, Seoul, Korea, November 30 - December 3, 2009 (Poster Presentation) . 2009. |
| Ma C. , Kwok W.M. and Phillips D.L. , Ultrfast Broadband Spectroscopic Study of the Excited States of DNA Oligomers Composed A and / or T, Femtochemistry IX: Femtochemistry, Femtobiology, and Femtophysics -- Frontries in Ultrafast Science and Technology, Beijing, China, August 8-13, 2009 . P-98: 166. |
| Researcher : Ma CW |
| List of Research Outputs |
| Chen Y. , Li K. , Lu W. , Chui S.Y. , Ma C.W. and Che C.M. , Photoresponsive Supramolecular Organometallic Nanosheets Induced by Pt II -- Pt II and C---H ... p Interactions, Angewandte Chemie Internationa l Edition . 2009, 48: 9909 –9913. |
| Researcher : Ma DL |
| Project Title: | Discovery of New Classes of Modulators for P-Glycoproteins based Multi-Drug Resistance by High-Throughput Virtual Screening |
| Investigator(s): | Ma DL, Leung CH, Lok CN |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 01/2009 |
| Completion Date: | 02/2010 |
| Abstract: |
| The problem of multidrug resistance (MDR) in cancer chemotherapy has drawn attention from both the academia and industry. A major cause of MDR in cancer is the overexpression of a membrane drug efflux transporter ABCB1, also known as permeability glycoprotein (P-gp) which reduces intracellular accumulation of drugs. Since the relationship between P-gp and MDR has been demonstrated, many have tried to develop P-gp inhibitors with the ultimate goal of reversing MDR. The first P-gp inhibitor was verapamil developed by Tsuruo et al.1 Subsequently, a range of compounds including calcium channel blockers,2,3 calmodulin inhibitors,4,5 indole alkaloids,6,7 cyclosporine,8–11 quinolines12 and steroid 13–15 have also been demonstrated to have P-gp inhibiting activity to different extents. Most of these so called first generation P-gp modulators suffered from their unacceptable toxicity. Searches for the congeners of these first generation MDR modulators resulted in the less toxic and more potent agents such as dexverapamil,16 dexniguldipine,17 PSC 833 (valspodar)18 and VX-710 (biricodar).19–21 Although these second generation MDR modulators showed some encouraging results, thei r uses are limited by their unpredictable pharmacokinetic interactions with the anticancer drugs.22 Thus, it is highly desirable to develop new scaffolds of P-glycoprotein modulators from natural occurring compounds with improved potency and less side-effect. With the aid of computer-aided drug design, we have successfully made use of the in silico homology model of P-glycoprotein for virtual drug screening to identify modulators from natural product database. Our preliminary in vitro studies have shown that these compounds can enhance cytotoxicity of known anti-cancer drugs. The research described in this proposal requires multi-disciplinary approach comprises synthesis of natural product lead derivatives designed in silico that stabilize closed form of P-glycoprotein plus an evaluation of their interaction using biophysics, biochemistry and cell biology. This collaborative resear ch would sustain the international reputation of academia in Hong Kong for drug discovery and have significant impact on organic synthesis, medicinal chemistry and cancer research. The objectives of this project are to (i) identify P-glycoprotein modulator hits by high-throughput virtual screening from natural products database, (ii) synthesize new analogues of natural product leads designed in silico as P-glycoprotein modulators through increase the drug accumulation and resulting in enhanced cytotoxicity of known anti-canc er drugs, (iii) investigate the modulating effect of the natural product leads on the stabilization of closed form of P-glycoprotein. (a) Discovery of new P-Glycoprotein Inhibitors by High-Throughput Ligand Docking Natural products are a valuable source of lead compounds and drug candidates for drug discovery. It is generally believed that natural products may possess the advantages of low toxicity and high molecular diversity compared to synthetic compounds. In order to search for P-glycoprotein modulators from a variety of natural products, we have employed a crystal structure of the homology of P-gl ycoprotein for in silico drug screening. In this approach, ligand docking is performed, followed by scoring to sort out promising drug candidates (i.e. with favourable protein-lig and binding). This virtual screening process can improve the rate of hitting the right compounds and reduce the number of drug candidates to be synthesized and tested, thus significantly shortening the drug discovery period. The in silico P-glycoprotein model can screen more than 20,000 compounds in the natural product library in a high-throughput manner. The experimental details for this study are presented as Supporting Information in Research Plan and Methodology. In this project, we have found that cytisine (1) is the best-scored compound, a natural product commonly found in the plant, Laburnum, using the in silico drug screening approach (Fig. 1). To the best of our knowledge, this compound has never been used as P-glycoprotein modulator. Our preliminary study of the anti-proliferation activity has shown that 1 can enhance cytotoxicity of known anti-cancer drugs, albeit less efficient; the IC50 value lies at the micromolar level only. Nevertheless, this natural compound is an important lead compound for developing new cytisine derivatives with improved modulating activities. (b) Rational Design of Natural Product Derivatives As P-Glycoprotein Modulators In order to explore new natural product derivatives with improved modulating activities, we have adopted structure-guide d in parallel synthesis. In this approach, the ligand functionality can be explored on the basis of receptor structural information, and the structure of the compound in complex with the protein model serves as the template for further drug design and synthesis. This approach can rapidly explore new derivatives from the lead compo und. |
| Project Title: | A Highly Selective and Rapid Switch-On Luminescent Probe for Mercury in Aqueous Media and Living Cells |
| Investigator(s): | Ma DL, Leung CH |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Applied Research |
| Start Date: | 06/2009 |
| Completion Date: | 05/2010 |
| Abstract: |
| Mercury pollution pervades the globe and remains a danger to human health and the environment.[1] Mercury(II) is one of the most potently toxic metal ions; it affects many different areas of the brain and their associated functions, resulting in symptoms such as tremors, vision problems, deafness, and losses of muscle coordination, sensation, and memory.[2] In addition to the brain, inorganic mercury can damage the heart, kidney, stomach, and intestines.[3] The US Environmental Protection Agency (EPA)’s estimates of annual total global mercury emissions from all sources–both natural and human-generated reach nearly 7500 tons per year.[4] Concerns over toxic exposure to mercury provide motivation to explore new methods for monitoring aqueous Hg2+ from biological and environmental samples. Current techniques for merc ury screening, including atomic absorption/emission spectroscopy[5a] and inductively coupled plasma mass spectrometry (ICP-MS),[ 5b] often require expensive and sophisticated instrumentation and/or sample preparation and their complexity makes them unsuitable for routine detection in a biochemistry laboratory. Fluorescence detection with Hg2+-responsive small molecule chemosensors offers a promising approac h for simple and rapid tracking of mercury ions for biological, toxicological, and environmental monitoring. An important practical challenge to achieving this goal is devising water-soluble fluorescent dyes that report Hg2+ selec tively over competing metal ion contaminants. However, the aforementioned methods are generally limited by nonspecific interference from Cu2+, Pb2+, and other competing metal ions, incompatibility with aqueous media, and/or delaye d or irreversible Hg2+ response. In particular, many mercury detection methods work in switch-off mode because heavy metal ions such as Hg2+ usually serve as fluorescence quenchers. The sensor schemes working in switch-off mode usually have limited sensitivity.[6] Alternative techniques based on other fluorescent probes using DNAzymes, polymer-protein complexes, and nanoparticl es have been demonstrated for the detection of Hg2+.[7] Nevertheless, each of these approaches exhibits some feature that limits its practical use, be it poor aqueous solubility, cross-sensitivity toward other metal ions, short emission wavelengths, and/or weak fluorescence intensities. We were inspired by the concept reported by Ono and co-workers that selective binding of Hg2+ ions to thymine–thymine (T–T) base pairs in DNA duplexes (Scheme 1).[8] Since the binding of mercury by T–T pairs is strong and highly selective, duplexes that contain a T–T pair are thermally stabilized in the presence of Hg2+ ions. In contrast, other heavy-metal ions, such as Cu2+, Ni2+, Pd2+, Co2+, Mn2+, Zn2+, Pb2+, Cd2+, Mg2+, Ca2+, Fe2+, and Ru2+, do not show any notable effects on duplex stability. Thus, a highly selective sensor for Hg2+ ions that relies on the selective binding of Hg2+ ions with a T–T pair could be envisaged. Photoluminescent iridium(III) complexes have emerged as a topical area of interest in inorganic photochemistry and phosphorescent materials for optoelectronic and luminescence signaling applications. Significant changes in the photophysical behavior and emission properties of iridium(III) complexe s may be induced by the presence of metal ion. In this context, the luminescent metallointercalator iridium(III) complex has received particular attention for the following reasons: (i) 3MLCT emission in the visible spectral region (the long emission lifetime of phosphorescence can enhance image signal stability and reduce the bac kground noise arising from fluorescence), (ii) an intriguing media dependence of the emission properties of iridium(III) complex has been observed; (iii) the iridium(III) complex can be synthesized conveniently and rapidly; and (iv) solubility and stability in aqueous staining solutions at room temperature (thus the use of organic solvents is not required for the optimal sensing of metal ions). In this work, we attempt to develop a simple and rapid luminescence approach using the polythymine oligonucleo tide T33 and a metallointercalator iridium(III) complex for the sensitive and selective detection of Hg2+ in aqueous media and living cells. The objectives of this project are to (i) identify a new class of metallointercalator as luminescent probe for mercury; (ii) synthesis new analogues of metal-based luminescent probe designed in silico with improved sensitivity and specificity; and (iii) systematic study of this new class of metal-based luminescent probe for selective detection of mercury in aqueous media and living cells. References 1) (a) Zahir, F.; Rizwi, S. J.; Haq, S. K.; Khan, R. H. Environ. Toxicol. Pharmacol. 2005, 20, 351–360. (b) Hylander, L. D.; Goodsite, M. E. Sci. Total Environ. 2006, 368, 352–370. (c) Zheng, N.; Wang, Q.; Zhang, X.; Zheng, D.; Zhang, Z.; Zhang, S. Sci. Total Environ. 2007, 387, 96–104. (d) Hemdan, N. Y. A.; Emmrich, F.; Faber, S.; Lehmann, J.; Sack, U. Ann. N.Y. Acad. Sci. 2007, 1109, 129–137. 2) (a) Zheng, W.; Aschner, M.; Ghersi-Egea, J.-F. Toxicol. Appl. Pharmacol. 2003, 192, 1–11. (b) Wojcik, D. P.; Godfrey, M. E.; Christie, D.; Haley, B. E. Neuroendocrinol. Lett. 2006, 27, 415–423. (c) Mutter, J.; Naumann, J.; Schneider, R.; Walach, H.; Haley, B. Neuroendocrinol. Lett. 2005, 26, 439–446. 3) (a) Baughman, T. A. Environ. Health Perspect. 2006, 114, 147–152. (b) Virtanen, J. K.; Rissanen, T. H.; Voutilaine n, S.; Tuomainen, T.-P. J. Nutr. Biochem. 2007, 18, 75–85. (c) Järup, L. Br. Med. Bull. 2003, 68, 167–182. (d) Vupputuri, S.; Longnecker, M. P.; Daniels, J. L.; Guo, X.; Sandler, D. P. Environ. Res. 2005, 97, 195–200. (e) Hoyle, I.; Handy, R. D. Aquat. Toxicol. 2005, 72, 147–159. 4) (a) Wilson, S. J.; Steenhuisen, F.; Pacyna, J. M.; Pacyna, E. G. Atmos. Environ. 2006, 40, 4621–46 32. (b) Pacyna, E. G.; Pacyna, J. M.; Steenhuisen, F.; Wilson, S. Atmos. Environ. 2006, 40, 4048–4063. (c) Pacyna, E. G.; Pacyna, J. M.; Pirrone, N. Atmos. Environ. 2001, 35, 2987–2996. 5) (a) Bloom, N.; Fitzgerald, W. F. Anal. Chim. Acta 1988, 208, 151–161. (b) Moreton, J. A.; Delves, H. T. J. Anal. Atom. Spectrosc. 1998, 13, 659–665. 6) (a) Zhu, X. J.; Fu, S. T.; Wong, W. K.; Guo, H. P.; Wong, W. Y. Angew. Chem., Int. Ed. 2006, 45, 3150–3154. (b) Che, Y. K.; Yang, X. M.; Zang, L. Chem. Commun. 2008, 1413–1415. (c) Descalzo, A. B.; Martinez-Manez, R.; Radeglia, R.; Rurack, K.; Soto, J. J. Am. Chem. Soc. 2003, 125, 3418–3419. (d) Miyake, Y.; Togashi, H.; Tashiro, M.; Yamaguchi, H.; Oda, S.; Kudo, M.; Tanaka, Y.; Kondo, Y.; Sawa, R.; Fujimoto, T.; Machinami, T.; Ono, A. J. Am. Chem. Soc. 2006, 128, 2172–2173. (e) Tang, Y. L.; He, F.; Yu, M. H.; Feng, F. D.; An, L. L.; Sun, H.; Wang, S.; Li, Y. L.; Zhu, D. B. Macromol. Rapid Commun. 2006, 27, 389–392. 7) (a) Thomas, J. M.; Ting, R.; Perrin, D. M. Org. Biomol. Chem. 2004, 2, 307–312. (b) Kim, I.-B.; Bunz, U. H. F. J. Am. Chem. Soc. 2006, 128, 2818–2819. (c) Lee, J.-S.; Han, M. S.; Mirkin, C. A. Angew. Chem., Int. Ed. 2007, 46, 4093–4096. (d) Huang, C.-C.; Chang, H.-T. Anal. Chem. 2006, 78, 8332–8338. (e) Huang, C.-C.; Chang, H.-T. Chem. Commun. 2007, 1215–1217. (f) Huang, C.-C.; Yang, Z.; Lee, K.-H.; Chang, H.-T. Angew. Chem., Int. Ed. 2007, 46, 6824–6828. 8) Ono, A.; Togashi, H. Angew. Chem., Int. Ed. 2004, 43, 4300–4302. |
| Project Title: | eCheminfo 2009 Drug Discovery Work shop Discovery of Drug-Like Hit of G-quadruplex Binding Ligand by High-Throughput Docking |
| Investigator(s): | Ma DL |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 07/2009 |
| Completion Date: | 07/2009 |
| Abstract: |
| N/A |
| List of Research Outputs |
| Chan D.S.H. , Lee H.M. , Che C.M. , Leung C.H. and Ma D.L. , A Selective Oligonoucleotide-Based Luminescent Switch-On Probe for the Detection of Nanomolar Mercury(II) ion in Aqueous Solution., Chemical Communications . 2009, 48: 7479-7481. |
| Chan D.S.H. , Lee H.M. , Yang F. , Che C.M. , Wong C.C., Abagyan R., Leung C.H. and Ma D.L. , Structure-Based Discovery of Natural-Product-like TNF-alpha Inhibitors, Angewandte Chemie International Edition . 2010, 49: 2860-2864. |
| Chan D.S.H. , Lee H.M. , Yang F. , Che C.M. , Wong C.C.L., Abagyan R., Leung C.H. and Ma D.L. , Structure-Based Discovery of Natural-Product-like TNF - a Inhibitors, Angewandte Chemie International Edition . 2010, 49: 2860-2864. |
| Law Y.K. , Wang M. , Ma D.L. , Al-Mousa F., Michelangeli F., Cheng S.H., Ng M., To K.F., Mok O.Y.F., Ko Y.Y. , Lam S.K. , Chen S.F. , Che C.M. , Chiu P. and Ko B.C.B., Alisol B, a novel inhibitor of the SERCA pump, induces autophagy, ER-stress and apoptosis, Molecular Cancer Therapeutics . 2010, 9: 718-730. |
| Lee H.M. , Chan D.S.H. , Yang F. , Lam H.Y., Yan S.C., Che C.M. , Ma D.L. and Leung C.H. , Identification of natural product Fonsecin B as a stabilizing ligand of c-myc G-quadruplex DNA by high-throughput virtual screening, Chemical Communications . 2010, 46: 4680-4682. |
| Leung C.H. , Lam W., Ma D.L. , Gullen E.A. and Cheng Y.C., Role of butyrate in the peptidoglycan-mediated mucosal immune response: regulation of nucleotide-binding and oligomerization domain 2 (NOD2)., European Journal of Immunology . 2009, 39: 3529-3537. |
| Sun R.W.Y. , Li C.K.L. , Ma D.L. , Yan J. , Lok C.N. , Leung C.H. , Zhu N. and Che C.M. , Stable anticancer gold(III)-porphyrin complexes: effects of porphyrin structure, Chemistry - A European Journal . 2010, 16: 3097-3113. |
| Wang P. , Leung C.H. , Ma D.L. , Yan S.C. and Che C.M. , Structure-Based Design of Platinum(II) Complexes as c-myc Oncogene Down-regulators and Luminescent Probes for G-quadruplex DNA, 17th Symposium of Chemistry Postgraduate Research in Hong Kong . 2010. |
| Wang P. , Leung C.H. , Ma D.L. , Yan S.C. and Che C.M. , Structure-Based Design of Platinum(II) Complexes as c- myc Oncogene Down-Regulators and Luminescent Probes for G-Quadruplex DNA, , Chemistry - A European Journal . 2010, 16: 6900-6911. |
| Wu P. , Ma D.L. , Leung C.H. , Yan S.C., Zhu N. , Abagyan R. and Che C.M. , Stabilization of G-Quadruplex DNA with Platinum(II) Schiff-base Complexes: Luminescent Probe and Down Regulation of c-myc Oncogene Expression., Chemistry - A European Journal . 2009, 15: 13008-13021. |
| Yan J. , Chow L.F. , Leung C.H. , Sun R.W.Y. , Ma D.L. and Che C.M. , Cyclometalated gold(III) complexes with N-heterocyclic carbene ligands as topoisomerase I poisons , Chemical Communications . Britain, Royal Chemical Society, 2010, 46: 3893 - 3895. |
| Researcher : Mak SK |
| Project Title: | Novel oligomeric and polymeric materials based on strongly interacting Pt(II) complexes for optoelectronic applications |
| Investigator(s): | Mak SK, Chan WK |
| Department: | Chemistry |
| Source(s) of Funding: | Germany/Hong Kong Joint Research Scheme |
| Start Date: | 01/2009 |
| Abstract: |
| (1) Develop new oligomers and polymers containing platinum(II) complexes which exhibit metal-metal int eractions; (2) study the tunability of emission and absorption by varying the intermolecular Pt-Pt separation and the chain length of oligomers and to elucidate the photophysical properties of the materials by spectroscopic investigations at different temperatures, pressures, and magnetic fields; (3) test the new materials for optoelectronic applications in external laboratories. |
| Project Title: | Design and Synthesis of Molecular Functional Materials for Dye Sensitized Solar Cells |
| Investigator(s): | Mak SK |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 12/2009 |
| Abstract: |
| Diminishing supply of fossil fuels from our Earth’s reserve and the global warming arises from the burning of fossil fuel are the global crises to human race. We are at the edge of the cliff and we need a cheap, pollution-free energy alternative. Solar energy, which can provide us a renewable, clean, environmental ben ign and unlimited energy source, is one of the options. Solar cell is the energy conversion device which changes sunlight into electricity. High purity silicon is used as the light absorbing material and conductor in the conventional solar cells. The problem with silicon cells is that the fabrication cost is expensive due to their manufacturing process involves high pressure and temperature, and highly pure silicon is difficult to obtain. Dye-sensitized solar cells (DSSCs) have been received lots of attention not only for academic curiosity but also for application reality. The dye-sensitized nanostructured solar cell was first developed by Grätzel’s group in 1991. The cell is on the verge of commercia lization offering a potential alternative for the currently used silicon based photovoltaic devices. An unprecedented conversion efficiency of 11% and could be manufactured from relatively cheap materials. The most efficient DSSCs up-to-date are based on ruthenium complexes. Some of the ruthenium complexes have been studied extens ively as model compounds for the understanding of the photochemical process in DSSC. The major part of the solar photon flux is located at red and infrared region. However, the study of using other metal complexes as photosensitiz er in DSSC is still sparse. For example, we have successfully demonstrated using rhenium (I) diimine complexes as photosensitizer in sublimable bulk-heterojunction solar cells. Encouraging power conversion efficiency (~ 2 %) was achieved with these materials. Therefore, the analogues of these rhenium (I) complexes would also be the suitable candidates for DSSC due to good stabilit y and intense absorption. Besides, the coordination chemistry of rhenium compounds is much simpler than the ruthenium complexes. The energy of the metal-to-ligand charge transfer transition can be easily fine tuned by modifying the diimine ligand by facile synthesis. The ligand will be functionalized with pi-conjugated hole transp ort moiety or donar-acceptor relay. The optical and electron transport properties are expected to be varied with different pi-conjugated systems. In addition, other transition metal complexes will also be explored for the use in DSSC. The photovoltaic devices based on this type of materials can be simply prepared by solution processing without involving expensive vacuum deposition techniques. The objectives of the proposed research are to: i) extend the absorption region of the organic ligands and organometallic compounds by chemical synthetic tailoring the structure of the molecules and different chromophores ii) fabrication of nanostructures of different inorganic semiconductors for DSSC iii) study the photovoltaic performances of the DSSC based on the new materials developed in this proposal |
| List of Research Outputs |
| Chan W.K. , Mak S.K. , Tam W.Y. and Leung Q.Y. , Functional Polymers For Photovoltaic Applications, The 9th International Symposium on Advanced Organic Photonics (ISAOP-9), Bunratty, Ireland . 2009. |
| Mak K... .Y..., Wong C.M. , Leung C... .W..., Huang H... .T..., Chan S... .B..., Shi J..., Mak S.K. , Chan M... .M... and Pong P.W.T. , Study of cellular behaviour on micro- and nano- structures, The Institution of Engineering and Technology Hong Kong Younger Members Exhibition/ Conference 2009 . |
| Mak S.K. and Chan W.K. , Applications of Metal Containing Polymers in Organic Solar Cells, In: A. S. Abd-El-Aziz, C. E. Carraher, C. U. Pittman, M. Zeldin, Macromolecules Containing Metal and Metal-like Elem ents, Volume 10: Photophysics and Photochemistry of Metal-Containing Polymers . Hoboken, John Wiley and Sons Inc., 2010, 159-185. |
| Mak S.K. , Cheung W.K. , Leung Q.Y. and Chan W.K. , Conjugated Copolymers Containing Low Bandgap Rhenium(I) Complexes, Macromolecular Rapid Communications . Wiley-VCH, 2010, 31: 875-882. |
| Mak S.K. , Wong H.L. , Leung Q.Y. , Tam W.Y. , Chan W.K. and Djurisic A. , The use of sublimable chlorotricarbonyl bis(phenylimino)acenaphthen e rhenium(I) complexes as photosensitizers in bulk-heterojunction photovoltaic devices, Journal of Organometallic Chemistry . ELSEVIER SCIENCE SA, 2009, 694: 2770-2776. |
| Mak S.K. , Leung Q.Y. , Li C.H. and Chan W.K. , Tuning the Electronic Properties of Conjugated Polymer by Tethering Low-Bandgap Rhenium(I) Complex on the Main Chain, Journal of Polymer Science Part A: Polymer Chemistry . Wiley Periodicals, Inc., 2010, 48: 2311-2319. |
| Researcher : Mo S |
| List of Research Outputs |
| Mo S. and Fung Y.S. , Solving The Problem of Interference From Hemolysis on The Determination of Free Bilirubin in Human Serum by Capillary Eletrophoresis - Frontal Analysis, Abstract of the 9th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2009) an d 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P4-08: pp236. |
| Researcher : Mo Y |
| List of Research Outputs |
| Mo Y. , Zheng X., Chen G. and Yan Y.J., Transient Electronic Dynamics Of Noninteracting Open Systems Beyond Linear Response, Journal of Physics: Condensed Matter . 2009, 21: 355301-1 to 355301-11. |
| Researcher : Ng CMD |
| List of Research Outputs |
| Laskin J., Yang Z.B., Ng C.M.D. and Chu I.K. , Fragmentation of α-Radical Cations of Arginine-Containing Peptides , Journal of the American Society for Mass Spectrometry . 2010, 21: 511-521. |
| Ng C.M.D. , Song T. , Siu S.O. , Siu C.K., Laskin J.U.L.I.A. and Chu I.K. , Formation, Isomerization, and Dissociation of alpha-Carbon-Centered and pi-Centered Glycylglycyltryptophan Radical Cations, J. Phys. Chem. B, . 2010, 114(6): 2270-2280. |
| Researcher : Ng FY |
| List of Research Outputs |
| Sun R.W.Y. , Ng F.Y. , Wong E.L.M. , Zhang J. , Chui S.Y. , Shek L. , Lau T.C. and Che C.M. , Dual anti-angiogenic and cytotoxic properties of ruthenium(III) complexes containing pyrazolato and/or pyrazole ligands , Dalton Transactions . 2009, 10712-10716. |
| Researcher : Ng KM |
| List of Research Outputs |
| Ng K.M. , Analysis of Melamine Cyanurate in Urine Using MALDI-MS, Separation Science . 2009, 1: 42. |
| Ng K.M. , How Practical is Surface-Assisted Laser Desorption/ Ionization Mass Spectrometry for Direct Herbal Tissue Analysis in Quality Control of Chinese Materia Medica?, Quality Control (Methodology), 8th Meeting of the Consortium for Globalization of Chinese Medicine, University of Nottingham, United Kingdom . 2009. |
| Ng K.M. , Mass Spectrometry and Its Application in Herbal Medici ne Analysis, Chinese Medicines Seminar, School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong . 2010. |
| Tang H.W. , Lu W. , Che C.M. and Ng K.M. , Double Imaging of Latent Fingerprints by Gold Nanoparticles-Assisted Imaging Mass Spectrometry , The 1st Asian & Oceanic Mass Spectrometry Conference, at Tsukuba International Congress Center, Tsukuba, Japan . 2010. |
| Tang H.W. , Lu W. , Che C.M. and Ng K.M. , Gold Nanoparticles and Imaging Mass Spectrometry: Double Imaging of Latent Fingerprints, Analytical Chemistry . 2010, 82: 1589–1593. |
| Researcher : Ng SM |
| Project Title: | Molecular cloning and functional characterization of the human cell cycle related kinase-i nteracting proteins |
| Investigator(s): | Ng SM, Lin MC |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 12/2005 |
| Abstract: |
| 1. To clone the genes encoding the proteins that specifically interact with CCRK in a yeast two-hybrid screening. 2. To elucidate the functional roles of the CCRK-interacting proteins in glioblastoma carcinogenesis. |
| Project Title: | The role of chemokine CC-motif receptor-like 2 (CCRL2) in colon cancer carcinogenesis |
| Investigator(s): | Ng SM, Lin MC |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 06/2008 |
| Abstract: |
| Colorectal cancer or colon cancer is the third most common cancer worldwide and it ranks only after breast and lung cancers in females, and prostate and lung cancers in males (Jemal et al., 2004). In Hong Kong, the incidence of CRC is increasing rapidly and it has become the second most common cancer with more than 3,500 new patients diagnosed every year (Hong Kong Cancer Registry, 2004). Compared with other par ts of the world, Hong Kong has more colon cancer patients under 40 years old (Yuen et al., 1997). Therefore, understanding the pathogenesis of colon cancer and identifying new molecular targets are critical for establishing novel therapeutic and diagnostic strategies against this potentially fatal disease. It has been estimated up to 20% of colon cancer cases are resulting from chronic intestinal inflammation. This is supported by the findings that inflammatory bowel diseases (IBD) like ulcerative colitis and Crohn’s disease, markedly increase the risk of colon cancer (Klamfer, 2008). Recently, it has been demonstrated that signals which promote inflammation like, nitric oxide (Ying et al., 2007), interleukin 22 (Ziesche et al., 2007), and STAT3 (Klampfer, 2008) are upregulated in colon cancer cells. Moreover, Kim et al. showed that expression of CXCR4, a well-characterized chemokine receptor for T cells, is associated with reduced overall survival and increased risk for recurrence and liver metastasis in colon cancer patients (Kim et al., 2005). Therefore, there is increasing evidence that chemokine receptors, which transduce signals for inflammation or the recruitment of immun e effector cells, may initiate the carcinogenesis of colon cancer. Chemokines are small proteins (~ 8-10 kD) that regulate cell migration. Cells that are attracted by chemokines follow a signal of increasing chemokine concentration towards the source. Currently, there are more than 50 known chemokines and 18 chemokine receptors which play crucial roles in many important cellular functions including leukocyte recruitment, angiogenesis, and inflammation (Proudfoot et al., 2002 ). Chemokine CC-motif receptor-like 2 (CCRL2) (also known as human chemokine receptor (HCR), CRAM, or CKRX) is a putative 7-transmembrane G protein-coupled chemokine receptor (Neote et al., 1993; Fan et al., 1998). The CCRL2 gene is located on chromosome 3p21, a locus within the main cluster of CC-chemokine receptor genes (Maho et al., 1999). The CCRL2 receptor was first isolated in a polymorphonuclear neutrophil (PMN) cDNA library (Fan et al., 1998) and is expressed on virtually all hemopoietic cells such as monocytes, T cells, dentritic cells, natural killer cells, and CD34+ progenitor cells (Patel et al., 2001; Migeotte et al., 2002), suggesting that this receptor is instrumental for cell-mediated immune responses and local inflammation. However, the role of CCRL2 in human cancers has never been elucidated. The objective of this project is to explore the potential role of CCRL2 in colon cancer carcinogenesis. We have obtained 12 local colon cancer tissue samples and their adjacent normal tissues and analyzed the expression profiles of CCRL2 using semi-quantitative RT-PCR. We found that CCRL2 mRNA expression was elevate d in 6 out of 12 (50%) of colon cancer tissues by more than 1.5-fold (Fig. 1A, B). Moreover, expression of CCRL2 was also detected in both LoVo and DLD1 human colon cancer cell lines (Fig. 1C). Therefore, we hypothesized that overexpression of CCRL2 may induce chronic intestinal inflammation and subsequently initiate carcinogenesi s in colon cancer patients. Results obtained from this study will provide new insights on the role of this chemokine receptor in colon cancer carcinogenesis. |
| Project Title: | Identification and characterization of chemotherapeutic drugs targeting cancer stem cells |
| Investigator(s): | Ng SM, Lin MC |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 03/2009 |
| Abstract: |
| Cancer cells within a tumor population often exhibit distinct proliferative and differentiation capacitie s, a phenomenon known as tumor heterogeneity. Early studies of spontaneous mouse leukaemias and lymphomas showed that the frequency of tumor-propagating cells ranged from 1% to 80-90% of the cells (Hewitt, 1958; Hamburger and Salmon, 1977). The mechanisms underlying tumor heterogeneity remain elusive, but at least two models have been put forward to explain the differences in the growing and regenerating capacities observed in cancer, namely the clonal evolution model (Nowell, 1976) and cancer stem cell model (Campbell, 2007). In the clonal evolution model, all undifferentiated cells have similar tumorigenicity and a dominant popu lation of proliferating cells drives tumorigenesis. By contrast, the cancer stem cell model proposes that a subset of cancer cells, referred to as cancer stem cells, is responsible for sustaining tumor growth. Cancer stem cells are considered as a distinct group of stem cells because they share important characteristics with normal stem cells. They have the abilities of self-renewal, generating additional cancer stem cells, and differentiating into phenotypically diverse cancer cells with lower proliferative potential. Cancer stem cells have been characterized in human acute myeloid leukaemia, breast cancer and brain cancer and surface markers have been identified in these cancer types. For example, in human breast cancer, cancer stem cells were found to express CD44 but little or no CD24 (CD44+CD24-/lo w) and have enriched tumor-initiating capacity; as few as 200 CD44+ CD24-/low cells were able consistently form tumors (Al-Hajj et al., 2003). In brain cancer, cancer stem cells were found to be those which express the human neural stem cell marker CD133 (CD133+), and they were accounted for almost all in vitro proliferative capacity (Singh et al., 2003). Collectively, these findings suggest that cancer stem cells play a crucial role in tumorigenesis and elimination of cancer stem cells is important for providing long-term disease-free survival in cancer patients. Eradication of cancer stem cells is still a major challenge for scientists mainly because they have stronger resistance to radiotherapy and chemotherapy than ordinary cancer cells. This resist ance may be attributed to better initiation of DNA damage response and overexpression of drug-resistance associated proteins within cancer stem cells (Pardal and Morrison, 2003). Because cancer stem cells lead to high tumorigenic potential and develop strong resistance to radio- and chemo-therapy, they may play a pivotal role in initiating the tumor recurrence. Thus, discovery of novel chemotherapeutic drugs which effectively or specifically target cancer stem cells are urgently needed. Gold-containing compounds have been shown to possess strong anti-tumor activities (Cagnoli et al., 1998; Marcon et al., 2002). However, compound containing gold in the +III oxidation state tend to be reduced in vivo to gold(I) and metallic gold as the intracellular environment is generally reducing (Tiekink, 2002). In collaboration with Prof. C. M. Che at the Department of Chemistry, we have rec ently synthesized a series of gold(III) meso-tetraporphyrins that are stable at physiological conditions (Che et al., 2003). The porphyrins ligands in these compounds stabilize the gold(III) center and carry it to their cellular targets. Their cytotoxicity is approximately 100-fold higher than that of cisplatin, a commonly used chemotherapeutic drug, in several human cancer cell lines (Che et al., 2003). Among these gold-containing compounds, we have previously demonstrated that gold (III) meso-tetraarylporphyrin 1a (gold-1a) exhibits strong anti-tumor activity in hepatocellular carcinoma (HCC) (Lum et al., 2006). We also tested the anti-tumor effect of gold-1a in other cancer types including nasophar yngeal carcinoma (NPC) and melanoma. In agreement with the findings in HCC, gold-1a also exhibits potent cancer-killing, anti-metastatic, and antiangiogenic actions in mice bearing NPC (Fig. 1). Therefore, we hypothesize that gold-1a may mediate its anti-cancer effects by targetin g cancer stem cells and thereby significantly inhibiting tumor growth, angiogenesis, and metastasis. The primary goal of this project is to evaluate the chemocytotoxic effects of gold-1a, the second-generation gold(III) meso-tetraarylporphyrins (synthesized based on the structure of gold-1a), and other chemotherapeutic drugs (e.g. cisplatin and dacarbazine) on cancer stem cell s. We will use the human NPC C666-1 cell line and human melanoma B16 cell line as our cell models because we have already shown previously that gold-1a potently inhibits the growth and/or metastasis of C666-1 cells and B16 cells in vivo (Fig. 1). The specific aims of this project are: 1. To examine the effects of gold-1a, the second generation gold-1a, and other chemotherapeut ic drugs on the expression of common stem cell markers in human NPC C666-1 and human melanoma B16 cell lines. 2. To determine the cytotoxic effects of gold-1a, the second-generation gold-1a, and other chemotherapeutic drugs on the cancer stem cells in vitro. References: Please refer to Section VII. |
| Project Title: | Development of novel nanopolymers for cancer gene therapy |
| Investigator(s): | Ng SM, Lin MC |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Applied Research |
| Start Date: | 03/2009 |
| Abstract: |
| Gene therapy is being developed as an alternative means of medical intervention for cancer and a variety of disorders (reviewed in 1, and references therein). Viral and non-viral vectors are the two principal gene delivery methods for gene therapy. Although a number of viral vectors such as adenovirus (Adv), adeno-associated virus (AAV), and lentivirus have been proposed, there are still concerns about their safety, immunogencity, and efficacy for therapeutic applications in humans (reviewed in 2). Therefore, non-viral gene delivery systems, which are based upon polymer/DNA complexes, are attracting increasing attention owing to their ease of structural modifications and potential in avoidin g the problems associated with viral vectors (reviewed in 3). An ideal polymer-based gene delivery vehicle should be bio-absorbable, non-toxic, non-immunogenic, stable, and able to access target cells after administration. Among several non-viral vectors that are currently in use, polyethylenimine (PEI), a polycationic copolymer, has shown good transfection efficiency both in vitro and in vivo (reviewed in 4). PEI has been used in a diversity of processes for many years. The basic unit of PEI consists of a backbone of two carbons followed by one nitrogen atom. PEI comes in two forms: linear and branched. The branched form is produced by cationic copolymerization from ethylenimine (aziridine) monomers via a chain-growth mechanism, with the branched site s arising from specific interactions between two growing copolymer molecules. Depending on its molecular weight, structure and dosages, PEI can be toxic to certain cells (reviewed in 5-7). It has been reported that branched PEIs with a molecular weight (MW) of 25,000 or greater display relatively high cytotoxicity, possibly because of the formation of large aggregates on the cell surface. Low molecular weight PEIs ( <1,800) show much less toxicity, but have very low transfection efficiency. Cyclodextrins (CyDs) are cyclic (alpha-1,4)-linked oligosaccharides of alpha-D-glucopyra nose containing a hydrophobic central cavity and hydrophilic outer surface. The most common CyDs are alpha-, beta- and gamma-CyDs, which are composed of six, seven, and eight D-glucopyranose units, respectively. It has been well documented that CyDs lack toxicity and immunogencity , and they are able to form inclusion complexes with a variety of guest molecules both in solution and in solid states. Although CyDs themselves are not effective gene carriers, they can act as a viral dispersant by enhancing both viral binding and internalization, resulting in an increase in adenoviral transduction in human colon adenocarcinoma Caco-2 cells. CyDs can disrupt biological membranes by forming complexes with phosphol ipids and cholesterols, which can assist the cellular uptake of polyamidoamine dendrimer/DNA particles and intracellular trafficking of DNA molecules. The major limitations of viral vectors as tools for gene therapy are the biosafety concerns and difficulties in preparing suff icient quantities of the viruses for clinical trials and future clinical use. In order to overcome these drawbacks, our team is focusing on developing nanoplymer for gene delivery. We have already formed a collaboration with Prof. Guping Tang at Zhejiang University on the developm ent of novel nanopolymers as gene delivery system for the treatment of glioblastoma and melanoma (selected refs. 8-14). Recently, we have jointly characterized one of the most promising nanopolymers which has high efficiency and low toxicity (patent and manuscript in preparation ). This nanopolymer consists of beta-cyclodextrin (beta-CyD) as the cross-linker for connecting low molecular weight polyethylenimine (PEI). We have further improved the gene targeting efficiency of beta-CyD-PEI by conjugating it with folic acid (CyD-PEI-FA) (Fig. 1). The result ing polymer has no detectable toxicity and exhibits high transduction efficiency comparable to that of leading commercial transfection reagents (Figs. 2 and 3). These findings have laid down a solid foundation for the further developing CyD-PEI-FA and other novel nano-biopolymers . The purpose of this research is to develop novel and highly efficient nanopolymers as gene delivery systems for cancer gene therapy. The specific aims of this project are: 1. To characterize the 3-dimensional structure, toxicity and the DNA binding affinity of CyD-PEI-FA / plasmid DNA complex in vitro in cell culture system s. 2. To determine the tumor targeting ability, tissue distribution, gene expression level, and toxicity of CyD-PEI-FA / plasmid DNA complex in vivo in mice. 3. To determine the therapeutic efficacy of CyD-PEI-FA / plasmid expre ssing interleukin 2 (pIL2) for the treament of melanoma in vivo in mice. References: 1. Curiel, DT.; Gerritsen, Winald R.; Krul, Mark R. L. Progress in cancer gene therapy. Cancer Gene Therapy (2000), 7(8), 1197-1199. 2. El-Aneed, Anas. An overview of current delivery systems in cancer gene therapy. Journal of Controlled Release (2004), 94(1), 1-14. 3. Vasir, Jaspreet K.; Labhasetwar, Vinod. Polymeric nanoparticles for gene delivery. Expert Opinion on Drug Delivery (2006), 3(3), 325-344. 4. Lungwitz, U.; Breunig, M.; Blunk, T.; Goepferich, A. Polyethylenimine-based non-viral gene delivery systems. European Journal of Pharmaceutics and Biopharmaceutics (2005), 60(2), 247-266. 5. Pietersz, Geoffrey A.; Tang, Choon-Kit; Apostolopoulos, Vasso. Structure and design of polycationic carriers for gene delivery. Mini-Reviews in Medicinal Chemistry (2006), 6(12), 1285-1298. 6. Hunter, A. Christy. Molecular hurdles in polyfectin design and mechanistic background to polycation induced cytotoxicity. Advanced Drug Delivery Reviews (2006), 58(14), 1523-1531. 7. Pack, Daniel W.; Hoffman, Allan S.; Pun, Suzie; Stayton, Patrick S. Design and development of polymers for gene delivery. Nature Reviews Drug Discovery (2005), 4(7), 581-593. 8. Shilei, Tang Guping, Gao Shujun, Ma Yuexia, Liu Beihui, Li Ying, Zhen Jieming, Ng Yee Kong, Kam Leong and Shu Wang. Repeared intrathecal administration of plasmid DNA complexed with polyethylene glycol-grafted polyethlenimine for prolonged transgene expression in the spinal cord. Gene Therapy. 2003;10:1179-1188. 9. Tang GP, Zeng JM, Gao SJ, Ma YX, Shi L, Li Y, Too H-P and Wang S. Polyethyene glycol-grafted polyetylenimine for improved CNS gene transfer: Effects of PEGylation extent. Biomaterials. 2003;24:2351-236218. 10. Y Li, J Wang, C Lee, C Y Wang, S J Gao, G.P.Tang, Y X Ma, Boon Soon, C T Lim, H Yu, H Q Mao, KW Leong and S Wang CNS gene transfer facilitated by a novel controlled release system based on DNA complexes of degradable polycation PPE-EA: a comparison with polyethylenimine/DNA complexes. Gene Therapy. 2004;11:109-114 11. G.P.Tang, Z.Yang and J.Yan A. A new biodegradable poly-amino acid: α,β-poly[(N-hydroxypropyl/a minoethyl)-DL-asppartami A potential non-viral vector for gene delivery. Drug Delivery. 2005;12:89-9. 12. Huanghong liang, Guping Tang, Qingqing Wang, Da Li, Two novel non-viral gene delivery vectors: low molecular weight polytheylenimine cross-linked by (2-hydroxypropyl)-b-cyclodextrin or (2-hydroxypropyl)-r-cyclodextrin. ChemComm. 2006:2382-2384 13. GP Tang, HY Guo, F.Alexis, X Wang, S.Zeng, T.M.Lim, J.Ding, Y.Y.Yang, S Wang Low molecular weight polyethylenimine linked by b-cyclodextrin for gene transfer into the nervous system. The Journal of Gene Medicine. 2006;8(6):736 -744 14. Da Li, Jingzhong Li, Qingqing Wang, Guping Tang, Hai Yu, Xuetao Cao. Combined targeting of polyethylenimine to FGF receptors and integrins on cells surface improves gene transfer efficiency. J. Biomater. Sci. Polymer Edn. 2007;18:545 |
| Project Title: | The role of CCRK as a novel CDK-act ivating kinase in human glioblastoma |
| Investigator(s): | Ng SM, Lin MC |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 07/2009 |
| Abstract: |
| 1) To identify proteins that associate with CCRK-cyclin H complex by co-immunoprecipitation and Tandem Affinity Purification (TAP); 2) To determine whether cyclin H and/or the interacting protein subunits are essential for the CAK activity of CCRK; 3) To examine if the CCRK-cyclin H holoenzyme complex is a bona fide cancer target. |
| List of Research Outputs |
| Li M. , Wang J. , Ng S.M. , Chan C.Y., He M.L., Yu F. , Lai L., Shi C. , Chen Y.C., Yew D.T., Kung H.F. and Lin M.C. , Adenosine Diphosphate-ribosylation Factor 6 is Required for Epidermal Growth Factor-induced Glioblastoma Cell Proliferation, Cancer . 2009, 115(21): 4959-4972. |
| Lin M.C. , Yu F. , Ng S.M. and Kung H.F., Knocking Down Interferon Induced Transmembrane Protein 1 (IFITM1) Inhibited Cell Proliferation and Invasion in Glioma Cells, Experimental Biology 2010; April 24-28, 2010; Anaheim, California, USA . 2010. |
| Xia H. , Ng S.M. , Kung H.F. and Lin M.C. , Inhibitory Effects of miR-200a on Nasopharyngeal Carcinoma Cell Growth, Migration and Invasion are Mediated by Different Targets, ASCB 49th Annual Meeting - December 5-9, 2009, San Diego, CA, USA. . 2009, 421. |
| Xia H. , Ng S.M. , Jiang S.S., Cheung K.C. , Sze J. , Bian X.W., Kung H.F. and Lin M.C. , miR-200a-mediated Downregulation of ZEB2 and CTNNB1 Differentially Inhibits Nasopharyngeal Carcinoma Cell Growth, Migration and Invasion, Biochemical and Biophysical Research Communications . 2009, 391(1): 535-541. |
| Xu Z. , Ng S.M. and Lin M.C. , Cell Cycle-Related Kinase Phosphorylates Casein Kinase Beta in Glioblasoma Cells, ASCB 49th Annual Meeting; December 5-9, 2009, San Diego, CA, USA. . 2009, 1017. |
| Yao H. , Ng S.M. , Li M. and Lin M.C. , An Effective Interleukin-2 Cancer Immunotherapy Delivere d by a Novel Polymeric nanoparticle in Melanoma, Annual Meeting of the International Society for Biological Therapy of Cancer; 28-31 October, 2009; Washington, USA . 2009. |
| Yao H. , Ng S.M. , Tang G. , Kung H.F. and Lin M.C. , Development of a Low-toxicity and High-efficiency Polymeric Nanoparticle for Gene Delivery, 2009 International Society for Cell & Gene Therapy of Cancer; Cork, Ireland; 2-4 September, 2009. . 2009. |
| Yao H. , Ng S.M. , Tucker W.O. , Tsang Y.K.T. , Man K. , Wang X.M., Chow B.K.C. , Kung H.F., Tang G. and Lin M.C. , The gene transfection efficiency of a folate-PEI600-cyclodextrin nanopolymer, Biomaterials . 2009, 30(29): 5793-5803. |
| Yu F. , Ng S.M. , Lum C.T. , Cheung K.C. , An X.M. and Lin M.C. , Functional Characterization of Interferon Induced Transmembrane Protein 1 (IFITM1) in Colorectal Carcinogenesis, 34th FEBS Congress: Life's Molecular Interactions; Prague, Czech Republic, 4-9, July, 2009. (P4-140, Published in the FEBS Journal) . 2009, 276 (s1): 134. |
| Researcher : Ng YW |
| List of Research Outputs |
| Cheung A.S.C. , Pang H.F. , Ng Y.W. and Chen G. , Electronic Transitions of Iridium Monoboride, The 65th OSU International Symposium on Molecular Spectroscopy, Columbus, Ohio, U.S.A., June 21-25, 2010 . WF02. |
| Researcher : Nie Z |
| List of Research Outputs |
| Nie Z. and Fung Y.S. , Determination of Binding Capacity of Albumin for Bilirubin by Microfluidic Chip-capillary Electrophoresis Based on Insitu Titration At a Circular Ferrofluid Driven Micromixer, Abstract of the 9th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P2-02: pp155. |
| Sun H. , Nie Z. and Fung Y.S. , Determination of binding capacity of albumin for bilirub in by Microfluidic chip-Capillary Electrophoresis based on insitu titration at a circular ferrofluid driven micromixer, Electrophoresis . 2010. |
| Researcher : Ou J |
| List of Research Outputs |
| Cividino P., Dheu-Andries M.-.L., Ou J. , Milet A., Py S. and Toy P.H. , Mechanistic Investigations of the Tributylphospine-Med iated Nitrone Reduction Reaction and Its Application in Cyclic Imine Synthesis, Tetrahedron Letters . 2009, 50: 7038-7042. |
| Researcher : Pang HF |
| List of Research Outputs |
| Cheung A.S.C. , Pang H.F. , Ng Y.W. and Chen G. , Electronic Transitions of Iridium Monoboride, The 65th OSU International Symposium on Molecular Spectroscopy, Columbus, Ohio, U.S.A., June 21-25, 2010 . WF02. |
| Cheung A.S.C. , Pang H.F. , Tam W.S. and Leung W.H. , Laser Spectroscopy of Nil: New Electronic States and Hyperfine Structure, The Journal of Chemical Physics . 2009, 131: 194301-1 - 194301-7. |
| Researcher : Pang HF |
| List of Research Outputs |
| Cheung A.S.C. , Pang H.F. , Ng Y.W. and Chen G. , Electronic Transitions of Iridium Monoboride, The 65th OSU International Symposium on Molecular Spectroscopy, Columbus, Ohio, U.S.A., June 21-25, 2010 . WF02. |
| Cheung A.S.C. , Pang H.F. , Tam W.S. and Leung W.H. , Laser Spectroscopy of Nil: New Electronic States and Hyperfine Structure, The Journal of Chemical Physics . 2009, 131: 194301-1 - 194301-7. |
| Researcher : Peng T |
| List of Research Outputs |
| Peng T. and Yang D. , Construction of a Library of Rhodol Fluorophores for Developing New Fluorescent Probes, Organic Letters . 2010, 12: 496-499. |
| Yang D. , Sun Z. , Peng T. , Wang L.H., Shen J. , Chen Y. and Tam P.K.H. , Synthetic fluorescent probes for imaging of peroxynitrite and hypochlorous acid in living cells, Methods Mol Biol. . 2010, 591: 93-103. |
| Yang D. , Sun Z. , Peng T. , Wang H.L., Shen J.G., Chen Y. and Tam P.K.H. , Synthetic fluorescent probes for imaging of peroxynitrite and hypochlorous acid in living cells, Methods in Molecular Biology . 2010, 591: 93-103. |
| Researcher : Phillips DL |
| Project Title: | Development of novel formulations for coatings and paints employing nanotechnology |
| Investigator(s): | Phillips DL, Chan WK |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Applied Research |
| Start Date: | 10/2004 |
| Abstract: |
| To collaborate with Manfield Coatings Co. Ltd., develop new coating and paint products especially those that employ nanotechnology additives that will meet the specifications of their customers who needs it for manufacturing new advanced electronic products. |
| Project Title: | Time-resolved resonance raman spect roscopic investigation of selected reactions of arylnitrenium ions with guanine derivatives |
| Investigator(s): | Phillips DL |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 08/2006 |
| Completion Date: | 07/2009 |
| Abstract: |
| (1) Carcinogenic aromatic amines are found in automobile exhaust, tobacco smoke, broiled meat and trace produces from some industrial processes. When metabolized, these types of aromatic amines cause damage to guanine bases in DNA and increase the probability for tumors or can cers. Arylnitrenium ions are the key intermediates in the metabolism of aromatic amines that selectively react with guanine in DNA. It is important to characterize these arylnitrenium ions and their reactions with guanine derivatives in as much detail as possible. There is not much vibrational spectropscopic level structural informationavailable for many arylnitrenium ions and their reactions. The broad objective of this proposal is to use time-resolved resonance Raman spectroscopy to obtain this missing structural information for selected arylnitrenium ions and thier reactions with guanine derivatives. The more specific objectives and issues are detailed in objectives 2-6.(2) Reactions of several para-phenyl subtituted phenylnitrenium ions like 2-fluoreny lnitrenium and 4-biphenylnitrenium ions predominantly form C8 adduct species after reaction with guanaine derivatives. Metabolism of 2-aminofluorene and 4-aminobiphenyl also form these same C8-adducts after in vivo and in vitro reaction with DNA. The reaction mechanism for how the se C8 adducts are formed is not clear and three different mechanisms have been proposed. We propose to use time-resolved resonance Raman spectroscopy to directly observe the formation of the reaction of the arylnitrenium ions with different guanine derivatives in order to better understand the reaction mechanism for formation of the C8 adducts. This work should elucidate what mech anism(s) are responsible for C8 adduct formation.(3) The degree of quinoidal character of some arylnitrenium ions has been found to vary significantly and it is not clear how this influences their chemical reactivity towards guanine derivatives. It is now known that the 4-biphenyl nitrenium ion has noticeably less quinoidal character than the 2-fluorenylnitrenium ion. We propose to use time-resolved resonance Raman spectroscopy to for both the 2-fluorenylni trenium and 4-biphenylnitrenium ions reactions with guanine derivatives to form intermediate species. This work should elucidate how the degree of quinoidal character affects the chemical reactivity of these arylnitrenium ions. (4) In vitro reaction of the carcinogen, N-hydroxy-2- aminonaphthalene with DNA forms adducts attached to the C8 and N2 positions of guanine while the reaction of N-hydroxy-1-aminona thylene with DNA in vivo and in vitro forms adducts attached to the O6 position of guanine. The reason for this substantial difference in the adducts formed from the reaction with DNA of these two closely related carcinogenic aminonapthalene derivatives is not known. We propose to use time-resolved resonance Raman spectroscopy to directly examine the structure and properties of the highly reactive 1-naphthylnitenium and 2-naphthylnitrenium ions and their reactions with selected guanine derivatives. This research will provide an improved understanding of the structure and chemical reactivity of naphthylnitr enium ions. (5) Nitroimidazoles are a kind of antibiotics that are effective against anaerobic bacterial and protozoal infections. The imidazolylnitrenium ion intermediates are thought to play an important role in the reductive metabolism of nitroimidazoles. We propose to use tim e-resolved resonance Raman spectroscopy to directly investigate the structure, properties and chemical reactivity of this interesting class of imidazolylnitrenium ions. Experiments will be done for the 1-methyl-2-imidazolylnitreni um ion and its reactions with GSH, phosphate and some guanine derivatives. This proposed research will help explain why imidazolylnitrenium ions are very selective towards GSH. This work may also help elucidate why nitroimidazoles are effective antibiotics while some para-phenyl substituted phenylnitrenium ions and naphthylnitreni um ions appear to be associated with the metabolism of potent carcinogens. (6) The proposed research associated with the objectives 1-5 above is for arylnitrenium ions and their reactions with mainly free nucleosides and substrate molecules. At present it is not understood how similar or different the chemical reactivity of arylnitrenium ion reactions with free nucleosides are from the corresponding reactions with larger systems like oligomers of guanine or genomic DNA. We would like to begin preliminary research to start to exami ne this issue. We propose to use time-resolved resonance Raman spectroscopy to study the reactions of the 2-fluorenylnitrenium ion with some oligomers containing guanine and perha ps calf thymus DNA. These results will be directly compared to those obtained for reactions with the free nucleosides and their reaction products so as to explore the influence of the oligomer or DNA environments on these arylnitr enium ion reactions. |
| Project Title: | Time-resolved studies of reactions related to chemical carcinogenesis and DNA photorepair |
| Investigator(s): | Phillips DL |
| Department: | Chemistry |
| Source(s) of Funding: | Croucher Senior Research Fellowships in Natural Sciences, Technology and Medicine |
| Start Date: | 01/2007 |
| Abstract: |
| Refer to hard copy |
| Project Title: | Time-Resolved Spectroscopy Studi es of Selected Coumarin and Benzoin Phototrigger Compounds |
| Investigator(s): | Phillips DL, Ma C |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 07/2007 |
| Abstract: |
| Time-resolved spectroscopy experiments will be done to characterize selected meta methoxy substituted benzoin phototriggers. This work is aimed at studying the structure and properties of the intermediates involved in the deprotection and formation of the side product reactions. This work is also aimed to help clearly identify these intermediates. The results from objective 1 will be used to develop an overall reaction mechanism(s) for the deprotection and formation of side product reactions for meta methoxy substituted benzoin class of compounds. The results from objective 1 will also be compared to previous results for an unsubstituted benzoin phototrigger (benzoin diethylphosphate) in order to better understand the similarities and differences in the reaction intermediates and reaction mechanisms of unsubstituted and meta methoxy substituted benzoin phototrigger compounds. Time-resolved spectroscopy experiments will be done to characterize selected (6,7-dimethoxycoumari n-4-yl)methyl and [7-(dimethyl-amino)coumarin-4-yl]methyl esters recently developed as proton phototriggers. This work is aimed at studying the structure and properties of the intermediates involved in the deprotection and formation of the side product reactions for these new proton phototriggers. This work is also aimed to help clearly identify these intermediates. The results from objective 3 will be used to develop an overall reaction mechanism(s) for the deprotection and formation of side product reactions for (6,7-dimethoxycoumarin-4-yl)methyl and [7-(dimethyl-amino)coumarin-4-yl]methyl esters. Time-resolved spectroscopy experiments will be done to characterize selected [7-[bis(carboxymethyl)-amin o]coumarin-4-yl]methyl esters of cyclic nucleoside monophosphates recently developed as phototriggers for studying cyclic nucleo tide dependent processes in biology. This work is aimed at studying the structure and properties of the intermediates involved in the deprotection and formation of the side product reactions for these new cyclic nucleoside monopho sphate phototriggers. This work is also aimed to help clearly identify these intermediates. The results from objective 5 will be used to develop an overall reaction mechanism(s ) for the deprotection and formation of side product reactions for [7-[bis(carboxymethyl)-amino]coumarin-4-yl]methyl esters of cyclic nucleoside monophosphates. |
| Project Title: | Time-Resolved Resonance Raman Spectroscopic Investigation of Selected Benzophenone-Derived Photo sensitizing Drugs and Related Compounds |
| Investigator(s): | Phillips DL |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 07/2008 |
| Abstract: |
| 1) TR3 experiments for benzophenone will be done in aqueous solution to provide a benchmark for comparison to other benzophenone derived compounds. These experiments will provide a detailed investigation for how the benzophen one triplet may be formed in aqueous environments and their reactivity toward water compared to other solvents like 2-propanol. 2) TR3 experiments will be done for ketoprofen (KP) in aqueous environments with varying pH. These experiments will be aimed at better understanding the significant pH dependent behavior of KP and to explicitly identify and structurally characterize the reaction intermediates involved in the reactions. Comparison of these results to those found in Objective 1 above for the BP system will be used to examine the effect of the substituent of KP on the benzophenone photochemistry. 3) Fenofibric acid (FA) was found to have significan tly lower phototoxicity compared to KP even though both appear to produce similar n-pi* triplets in organic solvents. TR3 experiments will be done to study the triplet state of FA and its subsequent reactions in both organic and aqueous solvents. Comparison of these TR3 results for FA to those from the experiments and calculations proposed in Objective 2 for KP will lead to a more in depth understanding for why FA has lower phototoxicity than KP. 4) Ketoprofen glycine (KPGly) was observed to have a long lived triplet state in aqueous solution while KP under these conditions und ergoes an efficient decarboxylation process. A TR3 and DFT investigation of the photochemistry of KPGly in both organic and aqueous solvents will be done. Comparison of these results for KPGly to those in Objective 2 for KP will provide additional insight into the significant substituent effect the Gly moiety has on the KP propert ies and its subsequent reactions. 5) The photophysical and photochemical properties of KPGly make it attractive to use to study KP-like triplet state interactions with amino acids and nucleosides that are the building blocks of proteins and DNA respectively. TR3 experiments will be done to directly probe the KPGly triplet state interactions with selected amino acids and nucleosid es. This work is aimed at providing a deeper understanding how benzophenone derived drugs cause damage to proteins and DNA. 6) The proposed TR3 experiments in Objective 5 present an interesting opportunity to cleanly produce a number of radicals from amino acids and nucleobases that can then be structurally characterized by TR3 spectroscopy under different environmental condition s. This work will be aimed at better understanding the structure, properties and chemical reactivity of selected amino acid radicals or nucleobase radicals that may be observed in the TR3 experiments. |
| Project Title: | Integrated Time-Resolved Spectroscopy Facility |
| Investigator(s): | Phillips DL, Yam VWW, Che CM, Wong WT, Yang D, Chan WK, Xu SJ, Djurisic A |
| Department: | Chemistry |
| Source(s) of Funding: | UGC One-off Special Equipment Grant Scheme |
| Start Date: | 12/2008 |
| Abstract: |
| The goal of this project is to set up and utilize a state-of-the-art “Integrated Time-Resolved Spectroscopy Facility” to investigate and characterize electronic excited states, photo-physical/chemical processes, and chemical reaction intermediates of interest in projects relevant to the development and discovery of novel chemical species and materials for applications as luminescent materials, photochromic materials, photo catalysts, molecular wires, molecular imaging, phototrigger materials, optoelectronic, biosensors, solar energy, photovoltaic materials and others. |
| Project Title: | Time-Resolved Resonance Raman an d Density Functional Theory Study of the Photochemistry of Selected TricyclicAntidepressant Drugs and Related Compounds |
| Investigator(s): | Phillips DL |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 02/2009 |
| Completion Date: | 01/2010 |
| Abstract: |
| Sunlight can make drugs or their products in biological systems undergo undesired reactions that damage proteins, DNA and/or RNA. Many of these reactionsthat harm humans are phototoxic in character and can result in medical conditionslike itching, rashes, angioneurotic edema, erythema, allergic purpura, exfoliative drmatitis, hypertrophic papillae of the tongue and pigmentation of the lenses and cornea of the eyes. A number of tricyclic antidepressants (TCA) drugs suffer from undesir able reactions that give rise to phototoxic effects. However, these TCA drugs have useful applications in the treatment of a number of medical conditions such as mental illnesses like depression, attention-deficit hyper-activity disorder, psychosis and others. Because of the usefulness of a number of TCA drugs there have been some studies of the photophysics and photochemistry associated with these drugs and related comopounds so as to better understand how the phototoxicity arising from the use of TCA drugs takes place. To best use these TCA drugs for medical purposes and to design and develop better TCA drugs for particular medical conditions and with lower phototoxicity, it is important to clearly identify the reaction intermediates and understand the reaction mechanisms that give rise to phototoxicity. Presently, the unambiguous and clear identification of the reaction intermediates and reaction mechanisms are still not well understood and this is particularly the case for structure/reactivity relationships and environmental effects on the photophysics and photochemical processes that result in the harmful phototoxic effects. Therre is limited structural information available at present for a number of important kinds of reaction intermediates at the vibrational spectroscopic level and limited quantum mechanical calculations of the reaction pathways associated with the photochemistry of TCA drugs. We propose to develop a project for a RGC grant application that employs a combination of time-resolved resonance Raman spectroscopy (TR3) experiments and quantum mechanical calculations of the intermediates and reaction pathways to investigate the reactions of selected TCA drugs and related compounds to acquire missing structural information for these systems. This proposed research should give rise to a deeper understanding of the properties, chemical reactivity and reaction mechanisms of the photophysical and photochem ical processes and their key reaction intermediates at the vibrational spectroscopic level of detail. This new information will be valuable in improving the employment and application of TCA drugs and in helping to design and develop improved TCA drugs with lower phototoxicity. This seed proposal will be used to explore the feasibility of synthesisng suitable amounts of precursor compounds for the proposed time-resolved spectroscopy experiments, to do preliminary time-resolved spectroscopy experiments and quantum mechanical calculations of selected TCA drugs to demonstrate the utility of the preceding methods to study the reaction intermediates and mechanisms. This work will allow us to clearly demonstrate the feasibility of ouor proposed GRF pro ject and to strengthen the proposal to be submitted to RGC. First, we will purchase and/or synthesize and purify gram quantities of a couple of TCA drugs and related compounds for use as a precursor in some time-resolved spectroscopy experiments. Second, we will attempt some preliminary time-resolved resonacne Raman spectr oscopy experiments to see if we can observe the reaction intermediates and acquire good quality spectra of these intermediates. We will also perform preliminary quantum mechanical calculations for probable reaction intermediates and reaction pathways to help with a preliminary interpretation of the data and write up preliminary results and submit them for publication in a top refereed intermational journal. The details of the proposed preliminary experim ents and calculations to achive the objectives and address the problems being examined in this project will be presented in the research plan and methodology sections. For references, please see the reference section attached to this proposal. |
| Project Title: | Faraqday Discsussions 145 Physical Organic Chemistry Ultrafast time-resolved transient infrared and resonance Raman spectroscopic study of the photo-deprotection and rearrangement reactions of p-hydroxyphenacyl caged phosphates |
| Investigator(s): | Phillips DL |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 09/2009 |
| Completion Date: | 09/2009 |
| Abstract: |
| N/A |
| Project Title: | Time-Resolved Spectroscopy and Density Functional Theory Investigation of Radicals of Nucleobases |
| Investigator(s): | Phillips DL |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 03/2010 |
| Abstract: |
| Chemical and photochemical reactions with DNA ca n lead to modification of the DNA so that it behaves differently than unmodified DNA in cells and living organisms. [1] A number of different chemicals can be metaobolized and cause oxidative damage to DNA. Free radicals , reactive oxygen species (ROS), ultraviolet light and ionizing radiation can all induce oxidative damage of DNA. The major sites affected are nucleobases and the sugar moiety in DNA.[2] The loss of a nucleobas e is one of the most common lesions or damage induced in DNA and this has been shown to be highly mutagenic.[3] The production of abasic positions in DNA affects the spatial conformation on the double helix and interferes with the proper function of the repair enzyme machinery. [4] The abasic positions in DNA can be formed when a C1' radical species is produced that can subsequently produce a 2-deoxyribonolactone (dL). For this process, the abstraction of the H1' hydrogen at the anomeric carbon by a suitable species is the most frequent inititation step. Sugiyama and coworkers found that excitation of 5-halouracil inserted into DNA formed dL in the adjacent adenine via a mechanism that includes product ion of a C1' sugar radical.[5] Chatgilaloglu, Newcomb and coworkers determined that the 2'-deoxyuridin-1'-yl radical reacts with molecular oxygen to produce dL as the final product.[6] DNA oxidation is thought to usually take place at guanine positions but there are some examples that the adenine radical cation may also be involved in charge-migration processes.[7] Although these nucleobases and the formation of the abasic position and associated sugar radicals are very important in understanding oxidative damage of DNA, there is relatively limited infomation about their oxidation chemistry and in particular for the formation of dL by photosensitization. Recently, several benzophenone-purine dyads have been developed so as to be able to investigate the photosensitized oxidation of adenosine and guanosine that may lead to production of dL.[8] These dyads had a S-ketoprofen (KP) moiety as the photosensitizing benzophenone unit and adenosine or guanosine as the purine part of the dyad.[8] Photoex citation of some of these dyads with 308 nm or 355 nm wavelengths that selectively excite the KP part of the dyad results in formation the same 2’-deoxyribonolactone species as a final product that is similar to the dL species.[8] The KP triplet state lifetime was observed to be greatly dependent on the conformation and position of attachment to the purine part of the dyad indicating that the effective interaction of the chromophores is highly sensitive to their relative geometry in space.[8] The KP triplet lifetimes were also found to be significantly depdnent on the solvent conditions and the length of the spacer between the two chromophore parts of the dyads and these results were consistent with a proposed electron transfer mechanism that forms a purine radical cation at the C1’ position that then deprotonates to produce a C1’ purine radical that subsequently reacts with water and/or oxygen to from the 2’-deoxyribonolactone species as a final product that is similar to the dL species.[8] While these studies have provided very important information about the kinetics and behavior of some of the species involved in the photosensitized oxidation of adenosine and guanosine that may lead to production of dL [8], there is little if any time-resolved vibrational spectroscopic characterization of these reactions and this information is important to determine the structure, identity and properties of the key reactive intermediates observed in these kinds of reactions. In addition, the time-resolved vibrational characterization of these reactions combined with density functional theory reaction pathway calculations should provide greater insight into the structure-chemical reactivity relationships as well as the role of explicit hydrogen bonding by water molecules in aqueous solvents. We propose to use time-resolved resonance Raman spectroscopy experiments and density functional theory calculations to provide this missing information in order to better understand the photosensitized oxidation of adenosine and guanosine that may lead to production of dL which is a commonly found DNA lesion. We plan to develop a project for a GRF grant proposal that utilizes a combination of time-resolved resonance Raman (TR3) spectroscopy experiments and density functional theory (DFT) calculations to study the chemical reaction intermediates and reaction pathways involved in the photosensitize d oxidation of adenosine and guanosine that may lead to production of dL which is a commonly found DNA lesion. This seed proposal will be used to investigate the feasibility of synthesizing large enough amounts of selected dyad compounds for preliminary TR3 experiments and DFT calculations. The proposed work will allow us to demonstrate the feasibility of the proposed research and strengthen the GRF proposal to be submitted to RGC. The research plan and methodology will be desc ribed in a subsequent section. |
| List of Research Outputs |
| Cao Q., Guan X. , George M.W., Phillips D.L. , Ma C. , Kwok W.M., Li M. , Du Y. , Sun X.Z. and Xue J. , Ultrafast Time-resolved Transient Infrared and Resonance Raman Spectroscopic Study of the Photo-deprotection and Rearrangement Reactions of p -Hydroxyphenacyl Caged Phosphates, Faraday Discuss . 2010, 145: 171-183. |
| Du Y. , Xue J. , Li M. , Guan X. , McCamant D.W. and Phillips D.L. , Unravelling the Reaction Mechanism for the Fast Photocyclisation of 2-Benzoylpyridine in Aqueous Solvent by Time-Resolve d Spectroscopy and Density Functional Theory Calculations, Chemistry - A European Journal . 2010, 16: 6967-6972. |
| El-Khoury P.Z., Kwok W.M., Guan X. , Ma C. , Phillips D.L. and Tarnovsky A.N., Photochemistry of Iodoform in Methanol: Formation and Fate of the Iso -CHl 2 -I Photoproduct , ChemPhysChem . 2009, 10: 1895-1900. |
| Kwok W.M., Ma C. and Phillips D.L. , Bright” and “Dark” Excited States of an Alternating AT Oligomer Characterized by Femtosecond Broadband Spectroscopy, Journal of Physical Chemistry B . 2009, 113: 11527-11534. |
| Li M. , Du Y. , Chuang Y.P. , Xue J. and Phillips D.L. , Water Concentration Dependent Photochemistry of Ketoprofen in Aqueous , Physical Chemistry Chemical Physics . 2010, 12: 4800-4808. |
| Ma C. , Kwok W.M., An H. , Guan X. , Fu Y. , Toy P.H. and Phillips D.L. , A Time-Resolved Spectroscopic Study of the Bichromophoric Phototrigger 3', 5'-Dimethoxybenzoin Diethyl Phosphate: Interaction Between the Two Chromophores Determines the Reaction Pathway, Chemistry - A European Journal . 2010, 16: 5102-5118. |
| Ma C. , Kwok W.M., An H. , Du Y. , Toy P.H. and Phillips D.L. , Femtosecond Transient Absorption and Nanosecond Time-resolved Resonance Raman Study of Photo-deprotection Reactions of Benzoin Caged Phototriggers , Femtochemistry IX: Femtochemistry, Femtobiology, and Femtophysics -- Frontries in Ultrafast Science and Technology, Beijing, China, August 8-13, 2009 . P-43: 111. |
| Ma C. , Kwok W.M. , Chan W.S. , Du Y. , Zuo P. , Kan T.W. , Toy P.H. and Phillips D.L. , Time-Resolved Spectroscopy Studies of the Photodeprotection Reactions of p -Hydroxyphenacyl Ester Phototrigger Compounds, Current Science . 2009, 97: 202-209. |
| Ma C. , Kwok W.M., An H. , Fu Y. , Toy P.H. and Phillips D.L. , Time-resolved Spectroscopy Studies of the Bichromophoric Phototrigger 3', 5'-dimethoxybenzoin Diethyl Phospate, The 2nd Asian Spectroscopy Conference, Seoul, Korea, November 30 - December 3, 2009 (Poster Presentation) . 2009. |
| Ma C. , Kwok W.M. and Phillips D.L. , Ultrfast Broadband Spectroscopic Study of the Excited States of DNA Oligomers Composed A and / or T, Femtochemistry IX: Femtochemistry, Femtobiology, and Femtophysics -- Frontries in Ultrafast Science and Technology, Beijing, China, August 8-13, 2009 . P-98: 166. |
| Phillips D.L. , Time-resolved Spectroscopy Studies of r -hydroxyphenacylester Phototrigger Compounds , Femtochemistry, Femtobiology and Femtophysics - Frontiers in Ultrafast Science and Technology (FEMTO IX), Peking University, Beijing, China, August 8-13, 2009 (Invited Lecture) . 2009. |
| Phillips D.L. , Water Assisted Dehalogenation Reactions Following Photoly sis of Selected Halogenated Compounds in Aqueous Solutions, International Conference on Green and Sustainable Chemistry, Singapore, August 3 - 5, 2009 (Invited Lecture) . 2009. |
| Tong S.M. , Law Y.C. , Kui C.F. , Zhu N. , Leung K.H., Phillips D.L. and Che C.M. , Ligand-to-Ligand Charge-Transfer Transitions of Platinum(II) Complexes with Arylacetylide Ligands with Different Chain Lengths: Spectroscopic Characterization, Effect of Molecular Conformations, and Density Functional Theory Calculations, Chemistry - A European Journal . 2010, 16: 6540-6554. |
| Researcher : Ren X |
| List of Research Outputs |
| Ren X. , Modeling Pattern Formation of Swimming E.coli (PhD Thesis) . 2010. |
| Researcher : Sham IHT |
| Project Title: | Magnitized dendrimers and hyperb ranched polymers for controlled delivery of targeted drugs |
| Investigator(s): | Sham IHT, Che CM, Kung H |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 11/2004 |
| Abstract: |
| To achieve controlled delivery of drugs to target sites using magnetized dendrimers and hyperbranched polymers as vehicles. |
| Researcher : Shek L |
| List of Research Outputs |
| Sun R.W.Y. , Ng F.Y. , Wong E.L.M. , Zhang J. , Chui S.Y. , Shek L. , Lau T.C. and Che C.M. , Dual anti-angiogenic and cytotoxic properties of ruthenium (III) complexes containing pyrazolato and/or pyrazole ligands , Dalton Transactions . 2009, 10712-10716. |
| Researcher : Shi C |
| List of Research Outputs |
| Li M. , Wang J. , Ng S.M. , Chan C.Y., He M.L., Yu F. , Lai L., Shi C. , Chen Y.C., Yew D.T., Kung H.F. and Lin M.C. , Adenosine Diphosphate-ribosylation Factor 6 is Required for Epidermal Growth Factor-induced Glioblastoma Cell Proliferation, Cancer . 2009, 115(21): 4959-4972. |
| Researcher : Shiu HYF |
| List of Research Outputs |
| Shiu H.Y.F. , Chong H.C., Leung Y.C., Wong M.K. and Che C.M. , A Highly Selective FRET-Based Fluorescent Probe for Detection of Cysteine and Homocysteine, Chemistry - A European Journal . 2010, 16: 3308-3313. |
| Researcher : Shum YT |
| List of Research Outputs |
| Liu Y. , Lok C.N. , Ko C.B. , Shum Y.T. , Wong M.K. and Che C.M. , Subcellular Localization of a Fluorescent Artemisinin Derivative to Endoplasmic Reticulum, Organic Letters . 2010, 12: 1420-1423. |
| Researcher : Siu AFM |
| Project Title: | Determinants of Efficacy of Human Topoisomerase I Inhibitors. A Molecular Dynamics and Bioinformatics Study |
| Investigator(s): | Siu AFM, Che CM, Leung CH, Wang Y |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 10/2009 |
| Abstract: |
| Topoisomerase I is of significant medicinal inte rest being the only target of the antitumor drug camptothecin. The discovery and development of camptothecin and its analogs (CPTs, Chart 1) as potent topoisomerase I (top1) inhibitors has been one of the greatest achievements of cancer chemotherapy in the past several decades. Topotecan (TPT) and irinotecan (CPT–11) are U.S. Fo od and Drug Administration–approved CPTs for the treatment of ovarian and colon cancers, respectively. CPTs bind at the interface of the top1–DNA cleavage complexes by intercalating at the cleavage site of DNA and by forming a network of hydrogen bonds with top1 residues. Collision between the CPTs–stabilized top1–DNA complexes and replication fork results in double–strand breaks and triggers a cascade of event leading to cancer cell death. However, CPTs have pharmacologic and clinical limitations. (i) CPTs rapidly convert to the inactive carboxylate forms. (ii) CPTs rapidly dissociate from the ternary complexes, which imposes long and/or repeated infusions for cancer treatment. (iii) A number of mutations in top1 confer resistance to CPTs. (iv) CPTs are substrates of drug efflux transporters; include ABCG2/BCRP/MXR, which confer resistance to CPTs. (v) Hematoglogical toxicity is a common side effect of CPTs due to the destruction of bone marrow progenitors. Considerable efforts are making by academia and pharmaceutical industry for the discovery of novel top1 inhibitors. Since then various classes of non–camptothecins (non–CPTs) compounds, includes indenoisoquinolines and indolocarbazoles (Chart 1), have been developed for clinical trials [Nature Reviews, 2006, 6, 789–802]. The present proposal aims to study the determinants of efficacy of top1 inhibitors using molecular dynamics and bioinfo rmatics approaches. The objectives of the project include the followings: Resistance to chemotherapy is the main reason for treatment failure in cancer patients. Top1 mutation is one of the reasons why the cancer cells confer resistance to CPT and/or non–CPTs in different extend. We will study the dynamic properties of drug– top1–DNA complexes with native (wild–type) and mutated top1 using molecular dynamics (MD) approaches, to address the question why top1 mutations confer resistance to CPTs and/or non¬–CPTs. Top1 inhibitors mediate their cytotoxicities by binding reversibly to transient top1–DNA covalent complexes. Cell killing occurs when the drug–top1–DNA ternary complex collide with replicat ion fork, which converts a single DNA strand break into a double DNA strand break. Top1 inhibitors dissociate from the ternary complexes with a significant variation in the drug dissociation rate. The principal investigator (PI) has established a molecular dynamics (MD) protocol to estimate the drug dissociation rates of CPTs [Journal of the American Chemical Society, 2008, 130, 17928–17937]. Using a similar protocol, we will gain mechanistic insight into dissociation rates of non–CPTs, compare to that of CPTs. National Cancer Institute (NCI) has explored the expression levels of proteins and genes in the 60 cancer cell lines (NCI–60) that has been used for establishing drug cytotoxicity patterns. Based on the data mining from the NCI databases, we will establish relationships between basal genes/proteins expression profiles in the NCI–60 cancer cells and cytotoxicities of top1 inhibitors against these cell lines using bioinformatics approaches [Molecular Cancer Therapy, 2007, 6, 820–832]. The molecular determinants (genes or proteins or pathways) associated with sensiti vity or resistance of top1 inhibitors will be identified and verified experimentally. |
| Project Title: | American Association for Cancer Research 101st Annual Meeting 2010 Molecular determinants of the anticancer efficacy of indenoisoquinolines |
| Investigator(s): | Siu AFM |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 04/2010 |
| Completion Date: | 04/2010 |
| Abstract: |
| N/A |
| List of Research Outputs |
| Che C.M. and Siu A.F.M. , Metal Complexes in Medicine with a Focus on Enzyme Inhibition , Current Opinion in Chemical Biology . 2010, 14: 255-261. |
| Researcher : Siu KS |
| List of Research Outputs |
| Siu K.S. , Development of Crosslinked Poly(Ethylenimine) as a Potential Nucleic Acid Delivery Agent (MPhil Thesis) . 2010. |
| Researcher : Siu SO |
| List of Research Outputs |
| Ng C.M.D. , Song T. , Siu S.O. , Siu C.K., Laskin J.U.L.I.A. and Chu I.K. , Formation, Isomerization, and Dissociation of alpha-Carbon-Centered and pi-Centered Glycylglycyltryptophan Radical Cations, J. Phys. Chem. B, . 2010, 114(6): 2270-2280. |
| Qi H. , Siu S.O. , Chen Y. , Han Y.F., Chu I.K. , Tong Y. , Lau A.S.Y. and Rong J. , Senkyunolide isomers H and I from Rhizoma Chuanxiong attenuate hydrogen peroxide-induced oxidative stress in human liver HepG2 cells via induction of heme oxygenase-1, 8th Meeting of Consortium for Globalization of Chinese Medicine (CGCM) . Nottingham, UK, 2009. |
| Qi H. , Siu S.O. , Chen Y. , Han Y.F., Chu I.K. , Tong Y. , Lau A.S.Y. and Rong J. , Senkyunolides reduce hydrogen peroxide-induced oxidative damage in human liver HepG2 cells via induction of heme oxygenase-1, Chemico-Biological Interactions . 2010, 183(3): 380-389. |
| Siu S.O. , Lam P.Y. , Lau E. , Yeung W.S.B., Cox D.M. and Chu I.K. , Chapter 9: N-Linked Glycoprotein Analysis Using Dual-Extractio n Ultrahigh-Preformance Liquid Chromatography and Electrospray Tandem Mass Spectrometry, In: Jianjun Li , Functional Glycomics -- Methods and Products . 2010. |
| Siu S.O. , Lam P.Y. , Lau E. , Yeung W.S.B. , Cox D.M. and Chu I.K. , N-Linked Glycoprotein Analysis Using Dual-Extraction Ultrahigh-Performance Liquid Chromatography and Elec trospray Tandem Mass Spectrometry , Functional Glycomics: Methods and Protocols . 2009, 5: 133-143. |
| Researcher : Siu SO |
| List of Research Outputs |
| Ng C.M.D. , Song T. , Siu S.O. , Siu C.K., Laskin J.U.L.I.A. and Chu I.K. , Formation, Isomerization, and Dissociation of alpha-Car bon-Centered and pi-Centered Glycylglycyltryptophan Radical Cations, J. Phys. Chem. B, . 2010, 114(6): 2270-2280. |
| Qi H. , Siu S.O. , Chen Y. , Han Y.F., Chu I.K. , Tong Y. , Lau A.S.Y. and Rong J. , Senkyunolide isomers H and I from Rhizoma Chuanxiong attenuate hydrogen peroxide-induced oxidative stress in human liver HepG2 cells via induction of heme oxyg enase-1, 8th Meeting of Consortium for Globalization of Chinese Medicine (CGCM) . Nottingham, UK, 2009. |
| Qi H. , Siu S.O. , Chen Y. , Han Y.F., Chu I.K. , Tong Y. , Lau A.S.Y. and Rong J. , Senkyunolides reduce hydrogen peroxide-induced oxidative damage in human liver HepG2 cells via induction of heme oxygenase-1, Chemico-Biological Interactions . 2010, 183(3): 380-389. |
| Siu S.O. , Lam P.Y. , Lau E. , Yeung W.S.B., Cox D.M. and Chu I.K. , Chapter 9: N-Linked Glycoprotein Analysis Using Dual-Extraction Ultrahigh-Preformance Liquid Chromatography and Electro spray Tandem Mass Spectrometry, In: Jianjun Li , Functional Glycomics -- Methods and Products . 2010. |
| Siu S.O. , Lam P.Y. , Lau E. , Yeung W.S.B. , Cox D.M. and Chu I.K. , N-Linked Glycoprotein Analysis Using Dual-Extraction Ultrahigh-Performance Liquid Chromatography and Electrospr ay Tandem Mass Spectrometry , Functional Glycomics: Methods and Protocols . 2009, 5: 133-143. |
| Researcher : So MH |
| List of Research Outputs |
| Chen R. , Cheng G. , So M.H. , Wu J., Lu Z., Che C.M. and Sun H. , Bismuth Subcarbonate Nanoparticles Fabricated By Water-in-oil Microemulsion-assisted Hydrothermal Process Exhibit Anti-helicobacter Pylori Properties, Materials Research Bulletin . 2010, 45: 654-658. |
| Ho C.M. , Yau K.W. , Lok C.N. , So M.H. and Che C.M. , Oxidative Dissolution of Silver Nanoparticles by Biol ogically Relevant Oxidants. A kinetic and Mechanistic Study, 17th Symposium of Chemistry Postgraduate Research in Hong Kong . 2010. |
| Ho C.M. , Yau K.W. , Lok C.N. , So M.H. and Che C.M. , Oxidative Dissolution of Silver Nanoparticles by Biolo gically Relevant Oxidants: A Kinetic and Mechanistic Study, Chemistry - An Asian Journal . 2010, 5: 285-293. |
| So M.H. , Ho C.M. , Liu Y. and Che C.M. , Aerobic oxidation of benzylic amines to imines catalyz ed by graphite-supported gold nanoparticles, Eleventh tetrahedron symopsium . 2010. |
| So M.H. , Liu Y. , Ho C.M. and Che C.M. , Graphite-Supported Gold Nanoparticles as Efficient Catalyst for Aerobic Oxidation of Benzylic Amines to Imines and N-Substituted 1,2,3,4-Tetrahydroisoquinolines to Amides: Synthetic Applications and Mechanistic Study, Chemistry - An Asian Journal . 2009, 4: 1551-1561. |
| So M.H. , Ho C.M. , Chen R. and Che C.M. , Hydrothermal Synthesis of Platinum-Group-Metal Nanoparticles by Using HEPES as a Reductant and Stabilizer, Chemistry - A Asian Journal . 2010, 5: 1322-1331. |
| So M.H. , Nanochemistry, Synthesis, Characterization and Application Studies of Metal Nanoparticles and Metalloporphyrin Nanowires (PhD Thesis) . 2010. |
| Researcher : So MH |
| List of Research Outputs |
| Chen R. , Cheng G. , So M.H. , Wu J., Lu Z., Che C.M. and Sun H. , Bismuth Subcarbonate Nanoparticles Fabricated By Water-in-oil Microemulsion-assisted Hydrothermal Process Exhibit Anti-helicobacter Pylori Properties, Materials Research Bulletin . 2010, 45: 654-658. |
| Ho C.M. , Yau K.W. , Lok C.N. , So M.H. and Che C.M. , Oxidative Dissolution of Silver Nanoparticles by Biologically Relevant Oxidants. A kinetic and Mechanistic Study, 17th Symposium of Chemistry Postgraduate Research in Hong Kong . 2010. |
| Ho C.M. , Yau K.W. , Lok C.N. , So M.H. and Che C.M. , Oxidative Dissolution of Silver Nanoparticles by Biologically Relevant Oxidants: A Kinetic and Mechanistic Study, Chemistry - An Asian Journal . 2010, 5: 285-293. |
| So M.H. , Ho C.M. , Liu Y. and Che C.M. , Aerobic oxidation of benzylic amines to imines catalyzed by graphite-supported gold nanoparticles, Eleventh tetrahedron symopsium . 2010. |
| So M.H. , Liu Y. , Ho C.M. and Che C.M. , Graphite-Supported Gold Nanoparticles as Efficient Catalyst for Aerobic Oxidation of Benzylic Amines to Imines and N-Substituted 1,2,3,4-Tetrahydroisoquinolines to Amides: Synthetic Applications and Mechanistic Stud y, Chemistry - An Asian Journal . 2009, 4: 1551-1561. |
| So M.H. , Ho C.M. , Chen R. and Che C.M. , Hydrothermal Synthesis of Platinum-Group-Metal Nanopartic les by Using HEPES as a Reductant and Stabilizer, Chemistry - A Asian Journal . 2010, 5: 1322-1331. |
| So M.H. , Nanochemistry, Synthesis, Characterization and Applica tion Studies of Metal Nanoparticles and Metalloporphyrin Nanowires (PhD Thesis) . 2010. |
| Researcher : Song H |
| List of Research Outputs |
| Yam V.W.W. , Song H. , Chan T.W. , Zhu N. , Tao C.H. , Wong M.C. and Wu L.X., Synthesis, Characterization, Ion-Binding Properties, and Fluorescence Resonance Energy Transfer Behavior of Rhenium(I) Complexes Containing a Coumarin-Appended 2,2′-Bipyridine, Journal of Physical Chemistry C . 2009, 113: 11674-11682. |
| Researcher : Song K |
| List of Research Outputs |
| Yang D. , Yip P.K.T. , Yang M., He W. , Chen H. , Song K. and Lo K.Y. , Stereoselective Cyclization Reactions through Palladium and Silver Catalysis, The 6th Asian-European Symposium on Metal Mediated Efficient Reactions, Singapore, June 1, 2010 . 2010. |
| Yu J.D., Ding W., Lian G.Y., Song K. , Zhang D. and Gao X., Selective Approach toward Multifunctionalized Lactams by Lewis Acid Promoted PhSe Group Transfer Radical Cyclization, Journal of Organic Chemistry . 2010, 75: 3232-3239. |
| Zhang Y.H., Song K. , Zhu N. and Yang D. , The Effect of Backbone Stereochemistry on the Folding of Acyclic b 2,3 -Aminoxy Peptides, Chemistry - A European Journal . 2010, 16: 577-587. |
| Researcher : Song T |
| List of Research Outputs |
| Ng C.M.D. , Song T. , Siu S.O. , Siu C.K., Laskin J.U.L.I.A. and Chu I.K. , Formation, Isomerization, and Dissociation of alpha- Carbon-Centered and pi-Centered Glycylglycyltryptophan Radical Cations, J. Phys. Chem. B, . 2010, 114(6): 2270-2280. |
| Researcher : Sun H |
| Project Title: | The role of metal ions on protein structural and conformational changes and folding - potential relevance to diseases |
| Investigator(s): | Sun H |
| Department: | Chemistry |
| Source(s) of Funding: | Matching Fund for NSFC Young Researcher Award |
| Start Date: | 02/2006 |
| Abstract: |
| To investigate the role of metal ions on protein structural and conformational changes and folding - potential relevance to diseases. |
| Project Title: | Biocoordination chemistry of bismuth and antimony: a metalloproteomic study |
| Investigator(s): | Sun H, He Q |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 10/2006 |
| Abstract: |
| 1. To investigate the transient effect of metallodrugs on microorganisms (e.g. Helicobacter pylori and Leishmaniasi s) by comparative proteomics using 2D-polyacrylamide gel electrophoresis (2-DE). 2. To identify the metal-binding proteins and peptides by the combination of IMAC and biological mass spectrometry. 3. To determine the metal-binding motifs by IMAC and other biophysical techniques. 4. To summarize the biocoordination chemistry of antimony and bismuth in microorganisms and study the mechanism of action of metallodrugs. |
| Project Title: | Chemical and Biochemical Characterizati on of the Histidine- and Glutamine-rich Protein, Hpn-like: Implications for the Role of Histidine-rich Proteins in Microorganisms |
| Investigator(s): | Sun H, Huang J |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 10/2007 |
| Abstract: |
| To examine the nickel binding properties of Hpn-like. The protein will be overexpressed in E. coli and the expression conditions will be further optimized. The thermodynamics and kinetics of nickel binding will be determined under a variety of conditions. To evaluate the effects of nickel (and other metals) on Hpn-like structure and stability. The potential changes in the secondary structure of the protein in the presence of Ni2+ and other metals will be determined and compared. The stability of the apo- and Ni2+-bound forms of the protein will also be investigated. To investigate the metal specificity of the protein in vivo. The influence of Ni2+ (and other metals) on the growth of E. coli with and without hpn-like gene will be examined. Similarly, the accumulation of metals in cells will also be studied via the measurement of intracellular Ni2+. To identify Hpn-like's binding-proteins and examine the role of Hpn-like in Ni2+ homeostasis. Both affinity column (together with MALDI/MS) and chemical cross-linking will be used for this purpose. |
| Project Title: | Structure-function of metal-binding proteins in Helicobacter pylori |
| Investigator(s): | Sun H, Chu IK, Huang J, Wong KB, Wong WT |
| Department: | Chemistry |
| Source(s) of Funding: | Collaborative Research Fund (CRF) - Group Research Project |
| Start Date: | 03/2008 |
| Abstract: |
| To identify key metal-binding proteins that are crucial for the survival and virulence of Helicobacter pylori by comparative genomics and proteomics; to validate and functionally characterize the promising proteins, and to over-express and structurally characterize selected metal-binding proteins (e.g. nickel transport/storage proteins). The objective of this group project includes using molecular genetic and comparative genomics/proteomics approaches, to elucidate the roles played by MBPs in cell growth regulation, stress response, biofilm formation, and virulence. Structural biology will provide hints for drug development. Our anticipated discoveries will provide a more comprehensive scenario of H. pylori on a molecular basis and may offer novel approaches for combating pathogenic bacteria and stomach cancer. |
| Project Title: | The Putative N-terminal Metal-binding Domain of Copper Transporter (hCtr1) and its Role in Copper(I) and Platinum Anticancer Drug Transport |
| Investigator(s): | Sun H |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 12/2008 |
| Abstract: |
| 1) The Met-rich (and His-rich) putative metal-binding domain of the N-terminus of hCtr1 will be expressed by recombinant DNA technology and the experimental condition will be optimized in order to obtain a high yield. 2) Thermodynamic and kinetic aspects of metal binding suh as Cu(I) and cisplatin will be illustrated. The potential effect of the protein on the hydrolysis of cisplatin and other Pt-drugs will also be followe d by fast protein liquid chromatography (FPLC) and NMR with the 15N-labeled cisplatin (cis-[Pt(NH3)2Cl2]. Kinetics of different anticancer agents will be compared. 3) The structures of the apo-, Cu(I)- and Pt-based anticancer agent-bound forms of the hCtr1_N in solution will be determined by circular dichrism (CD), multidimension al/multinuclear NMR techniques, and their structures will be compared. The metal binding site(s) will also be identified based on the changes of chemical shifts or coupling betwee n the metal (Pt(II)) and the binding residues (e.g. 1J(Pt, N) and 2J(Pt, C)). 4) The migration of the cisplatin and carboplatin from its hCtr1-bound to other nitrogen-containing bio-molecules such as 5’-GMP, dGpG and single- and double-stranded DNA fragments will be investigated by 2D [1H, 15N] HSQC NMR with the aid of 15N-labeled cisplatin (and other Pt-drugs) and doubly labeled protein. 5) The PI will carry out cutting edge research to explore the mechanism of copper and Pt-anticancer drug uptake and the relation to the mechanism of action of cisplatin. This project is expected to be completed in 24 months with singificant reduction of the proposed budget. |
| Project Title: | A metallomic approach to analyze bismuth- and nickel-binding proteins in cells |
| Investigator(s): | Sun H |
| Department: | Chemistry |
| Source(s) of Funding: | France/Hong Kong Joint Research Scheme - Travel Grants |
| Start Date: | 01/2009 |
| Abstract: |
| Refer to hard copy |
| Project Title: | Structrual study of SlyD, a metallochape rone with PPIase activity |
| Investigator(s): | Sun H |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 04/2009 |
| Completion Date: | 04/2010 |
| Abstract: |
| (1) To overexpress and purify H pylori SlyD and its mutants. The proteins will be overexpressed in E. coli and the expression conditions will be further optimized. (2) To examine the nickel (and other metal) binding properties of the proteins. The thermodynamics and kinetics of nickel binding will be determined under a variety of conditions. (3) To evaluate the effects of nickel (and other metals) on protein structures and stabilities. The potential changes in the secondary structure of the protein in the presence of Ni2+ and other metals will be determined and compared. (4) To determine the three dimensional structure of the protein by NMR spectroscopy. (5) To investigate the roles of key residues play on the function of SlyD, especially on its interaction with other metallchaperones. |
| Project Title: | HKU Overseas Fellowship Awards 2009-10 |
| Investigator(s): | Sun H |
| Department: | Chemistry |
| Source(s) of Funding: | HKU Overseas Fellowship Awards |
| Start Date: | 09/2009 |
| Abstract: |
| To visit the UCLA and Celtech, USA to establish a platform for metals in life processes using the state-of-the-art metallomic and metalloproteomic techniques in combination with inorganic structural biology and bioinformatics , and to do preparation work for the book "Biological Chemistry of Arsenic, Antimony and Bismuth". |
| Project Title: | Nickel (Ni2+) Trafficking between Metallochaperone Proteins |
| Investigator(s): | Sun H, Hao Q |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 10/2009 |
| Abstract: |
| To examine nickel binding properties of these proteins and their complexes; to evaluate the effects of nickel (and other metals) on structures and stabilities of these chaperones and on the formation of protein complexes (e.g. HypA•HypB and HypA•UreE); to determine the structures of the apo-, and metal-bound forms of Hp HypA, HypB and UreE, and identify the interfaces of the protein complexes, HypA•HypB and HypA•UreE; to determine th e structures of the protein complexes, HypA•HypB and HypA•UreE, and ultimately to understand the biocoordination chemistry of nickel and the molecular basis of nickel trafficking in cells. |
| Project Title: | Tracking metals in cells by metallomics: insights into the metal-associated pathophysiologica l processes |
| Investigator(s): | Sun H, Watt RM |
| Department: | Chemistry |
| Source(s) of Funding: | NSFC/RGC Joint Research Scheme |
| Start Date: | 02/2010 |
| Abstract: |
| To track key metals (Fe, Zn and Ni) within the proteome of H. pylori (and related oral bacterial pathogens) using both gel electrophoresis (2DE) coupled with advanced nuclear analytical techniques such as synchrotron radi ation microbeam scanning X-ray fluorescence (SRXRF); to identify metal-binding proteins and subsequently elucidate metal-binding motifs, using a combination of metallomics and metalloproteomics such as immobilized metal affinity chromatography and various biological mass spectrometry. Metal binding motifs will be identified and examined by spectroscopy and bioinformatic methods; to determine the structure and function of key metalloproteins involved in metal-associated pathophysiological processes (e.g. metal chaperones and metal storage proteins) by NMR, X-ray crystallography and XAS; to visualize the localization and concentratio n of key metal-binding proteins or/and motifs in 2-DE gels and cells by fluorescence spectroscopy. A fluorescence imaging agent, a conjugate of a fluorophore with a metal chelation moiety, will be prepared. |
| Project Title: | Biocoordination of iron in human transferrin: insights into the iron transport in blood plasma |
| Investigator(s): | Sun H, Yang N |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 03/2010 |
| Abstract: |
| Transferrin, a major source of iron for all cells and the only physiological source of iron for most, involves the specific recognition of Fe3+ with an obligatory synergistic anion [1]. Human serum transferrin (hTF) is an 80 kDa glycoprotein with a concentration of 35 μM (2.5 mg/ml) in blood plasma, and can be recognized by transferrin receptor (TfR) on the cell surface when hTF is fully loaded with two ferric ions. Moreover, the affinity of metal-loaded transferrin for the TfR is much higher than that of apo-transferrin. The Fe2 -hTF is internalized by clathrincoated vesicles into endosomes, where the pH is lower than extracellular environment, and then the Fe3+ is released [2,6] (Fig. 1). Since hTF is only 30% saturated with Fe3+, the protein therefore has potential to bind other metal ions and has been regarded as a “carrier” for metallodrugs [1]. Metal ions such as Bi3+, Ga3+, Gd3+, Ti4+ and Pu4+ have been found binding to transferrin under biologically relevant conditions [1]. The strength of metal binding to human serum transferrin was rationalized and found to be simply correlated with metal acidity (pKa), and it was subsequently confirmed by the discovery of Ti4+ coordinated to hTF [3]. Crystal structures of apo- and iron-bound lactoferrin and ovotransferrin, members of transferrin family, were reported [4]. Surprisingly, only the apo-form of human serum transferrin was determined by X-ray but not the iron-bound form (except Zuccola’s unpublished preliminary structure). The apo-hTF consists two lobes (N- and C-lobe) which are connected by a short peptide linker (residues 332-338), and each lobe can be separated into two subdomains, namely N1 and N2 for the N-lobe; C1 and C2 for the C-lobe [4]. N1- (residues 1-92 and 247-331) and C1-subdomain (residues 339-425 and 573-679) consist of two discontinuous sections, whereas N2- (residues 93-246) and C2-subdomain (residues 426-572) are composed of a single region of continuous polypeptide [4]. The subdomains in each lobe can rotat e around a “hinge” to form the “open” and “close” conformations, corresponding to the iron free and bound forms of hTF, respectively [1]. Although both “hinges” between subdomains are composed by two β strands in each lobe, one of the strands in the C-lobe is relatively shorter, which probable accounts for the different rates of Fe3+ binding and release in two lobes [1]. Based on lactoferrin and ovotransferrin data, each lobe of transferrin contains a distorted octahedral Fe3+ binding site consisting of two Tyr, one His, one Asp, and one bidentate carbonat e anion. Carbonate serves as the synergistic anion in vivo and has a higher affinity than most of other anions, but oxalate is also efficient in promoting metal ion binding. Moreover, a metal-oxo cluster is observed at the metal binding site in ferric-iron-binding protein (Fbp), a transferrin analogue. The PI and Co-I’s exciting preliminary data showed that the iron-bound human tr ansferring can be crystallized and the resolution can reach to ca. 3 Å at the in-house” diffractometer. Upon appropriate optimization of the crystallization condition and using synchrotron source, high resolution structure of the iron-bound structure can readily be determined. The key issues of the project: (1) Structure determination of the Fe1-hTF and Fe2-transferrin, and investigation of the biocoordination chemistry of iron as well as the potential conformational changes of the protein, which is crucial for transferrin-transferrin receptor recognition; (2) Identification of the glycans from the protein structure and investigation of the biological consequence; (3) Investigation of the effect of synergistic anions, e.g. carbonate and oxalate on iron binding and comparison their conformational differences; (4) Crystallization of platinum-bound forms of transferrin and identify binding site(s) of platinum anticancer drugs using Fe2-hTF as a template. |
| List of Research Outputs |
| Chen R. , Cheng G. , So M.H. , Wu J., Lu Z., Che C.M. and Sun H. , Bismuth Subcarbonate Nanoparticles Fabricated By Wat er-in-oil Microemulsion-assisted Hydrothermal Process Exhibit Anti-helicobacter Pylori Properties, Materials Research Bulletin . 2010, 45: 654-658. |
| Cheng T. , Li H. , Xia W. and Sun H. , Structure and function study of SlyD in Helicobacter pylori , 21st IUBMB and 12th FAOBMB International Congress of Biochemistry and Molecular Biology, Shanghai, China, August 2-7 . 2009. |
| Cun S. and Sun H. , A zinc-binding site by negative selection induces metallodrug susceptibility of an essential chaperonin, Proceedings of the National Academy of Sciences, USA . 2010, 107: 4943-4948. |
| Du X. , Wang X. , Chan D.S.B. and Sun H. , Expression, purification and characterization of the N-terminal domain of the human copper transporter (hCtr1), 14th International Conference on Biological Inorganic Chemistry, Nagoya, Japan, July 25-30 (published in J. Biol. Inorg. Chem. 2009, 14, Suppl1, P534) . 2009, 14. |
| Ge R. , Chu I.K. and Sun H. , Nuclear-based metallomics in metal-based drugs, "Advanced nuclear analytical techniques for metallomics and metalloproteomics" (Edited by C.Y. Chen, Z.F. Chai, YX Gao) . Royal Society of Chemistry, 2010, 265-298. |
| Guo W. , Lau K.M., Sun H. and Fung Y.S. , Microfluidic Chip-Capillary Electrophoresis for Emergency Onsite Biomedical Analysis, Separation Science . 2010, 2: 3-10. |
| Huang J. , Sun H. , Tanner J.A. and Watt R.M. , Determine the functions of the putative metal-binding domain of SARS-CoV helicase, Hong Kong Medical Journal . 2009, 15(5) Supplement: 6:15-16. |
| Qi S. , Sun H. and Huang J. , Expression and Purification of Mutated hpn Protein, and Studies of Function of Cystein Residues in hpn, 14th Research Postgraduate Symposium, December 2 & 3, 2009, The University of Hong Kong . 2009. |
| Qi S. , Sun H. and Huang J. , Expression and purification of mutated hpn protein and studies of cysteine residues in hpn, 14th International Conference on Biological Inorganic Chemistry, Nagoya, Japan, July 25-30, 2009 (published in J. Biol Inorg Chem. 2009, 14, Suppl1, P606) . 2009. |
| Sun H. , Lau K.M. and Fung Y.S. , A New Capillary Electrophoresis Buffer For Determining Organic and Inorganic Anions in Electroplating Bath with Surfactant Additives, Journal of Chromatography A . 2010, 1217: 3244-3250. |
| Sun H. , Croucher Senior Research Fellow (2010-2011), Croucher Foundation . 2010. |
| Sun H. , Nie Z. and Fung Y.S. , Determination of binding capacity of albumin for bilirubi n by Microfluidic chip-Capillary Electrophoresis based on insitu titration at a circular ferrofluid driven micromixer, Electrophoresis . 2010. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Development of Molecularly Imprinted Polymer Based Piezoelectric Quartz Crystal Biosensori , Extended Abstract of 12th International Symposium on Electroanalytical Chemistry (12th ISEC), Changchun, China, August 12-15, 2009 . Page 151. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Development of Molecularly Imprinted Polymer based Piezoelectric Quartz Crystal Biosensor, Conference proceeding of the The 12th International Symposium on Electroanalytical Chemistry, August 12-15, 2009, . 2009, 151. |
| Sun H. , Guest Professorship, Wuhan Institute of Technology . 2010. |
| Sun H. , Lau K.M. and Fung Y.S. , Hui Sun, Kwokman Lau and Yingsing Fung. A new capillary electrophoresis buffer for determining organic and inorganic anions in electroplating bath with surfactant additives, Journal of Chromatography A . 2010, 1217: 3244-3250. |
| Sun H. and Fung Y.S. , Nucleic Acid Based Piezoelectric Quartz Crystal Biosensor for Dectection of E. Coli , 12th International Symposium on Electroanalytical Chemistry (12th ISEC), Changchun, China, August 12-15, 2009 . 2009. |
| Sun H. and Fung Y.S. , Nucleic Acid Based Piezoelectric Quartz Crystal Biosensor for Detection of E. coli, Extended Abstracts of 12th international Symposium on Electroanalytical Chemistry (12th ISEC), Changchun, China, August 12-15, 2009 . Page 20. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Nucleic Acid Based Piezoelectric Quartz Crystal Biosensor for Detection of E.coli , Conference Proceeding of The 12th International Symposium on Electroanalytical Chemistry, Changchun, China, August 12-15, 2009 . 20. |
| Sun H. , Albano D.R.B. and Fung Y.S. , Piezoelectric Quartz Crystal Biosensor for Detection of Protein Biomarker for Infective Disease, Conference proceeding of Biosensors 2010, 20th Anniversary World Congress on Biosensors, Glasgow, United Kingdom, May 28 to May 30, 2010 . P.1.10. |
| Sun H. , Rahula A.D. and Fung Y.S. , Piezoelectric Quartz Crystal Biosensor for Detection of Protein Biomarker for Infective Disease , Abstract, The 20th World Congress on Biosensors (Biosensors 2010), May 26-28, 2010, Glasgow, United Kingdom . 2010, P.1.10. |
| Sun X. , Baker H.M., Ge R. , Sun H. , He Q. and Baker E.N., Crystal structure and metal binding properties of the lipoprotein MtsA, responsible for iron transport in Streptococcus pyogenes , Biochemistry . 2009, 48: 6168-6190. |
| Tian Y., Hou X., Wen L., Guo W., Song Y., Sun H. , Wang Y., Jiang L. and Zhu D., A biomimetic zinc activated ion channel, Chemical Communication . 2010, 46: 1682-1684. |
| Wang X. , Du X. , Li H. , Chan D.S.B. and Sun H. , Effect of the N-terminal of the human high affinity copper transporter 1 (hCtr1) on cisplatin hydrolysis and uptake, 14th International Conference on Biological Inorganic Chemistry, Nagoya, Japan, July 25-30 (published in J. Biol. Inorg. Chem. 2009, 14, Suppl 1, P305) . 2009. |
| Wu Z.Y., Liu Q., Liang X., Yang X., Wang N.Y., Wang X. , Sun H. , Lu Y. and Guo ZJ , Reactivity of platinum-based antitumor drugs towards a Met- and His-rich 20mer peptide corresponding to the N-terminal domain of human copper transporter 1, Journal of Biological Inorganic Chemistry . 2009, 14: doi: 10.1007/s00775-009-0576-7. |
| Xia W. , Li H. , Sze K.H. and Sun H. , Structure of a nickel chaperone, HypA from Helicobacter pylori reveals two distinct metal binding sites, Journal of American Chemical Society . 2009, 131: 10031-10040. |
| Xia W. , Li H. , Sze K.H. and Sun H. , The Bifunctional Roles of Nickel Ions in Helicobacter pylori [NiFe] - Hydrogenase Maturation Pathway, , Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic Univer sity, Hong Kong, April 24, 2010 . I-78. |
| Researcher : Sun H |
| Project Title: | Piezoelectric Quartz Crystal (PQC) Sensing System for Environmental, Clinical and Biomedical analysis using Molecular Imprinting and Microfluidic Technology |
| Investigator(s): | Sun H, Fung YS |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 02/2009 |
| Abstract: |
| The proposal aims to develop Piezoelectric Quartz Crystal (PQC) Sensing system for environmental and biomedical applications using Molecular Imprinting Technology to develop selective coating and Microfluidics technology to enhance sensitivity and reduce interference by manipulation of fluid flow. In this proposal, two research lines previous developed in our laboratory will be combined: firstly, the development of methodology based on microfluidic device, and secondly, the development of various PQC sensors based on molecular imprinting for biosensing of bacteria and food contaminant. Through integration of two lines of research, portable sensors can be developed to remove sample matrix interferences for field and clinical application, in particular for analyzing whole blood samples with high organic contents. Important proteins such as markers for diabetics and cancer, as well as sucrose and glucoproteins will be explored for application using PQC sensor with molecul arly imprinted sensing film in blood or beverage. Demand for on-chip biochemical analysis systems (often called Lab-on-a-Chip) is growing rapidly, since they can offer a fast, efficient and low cost assay. Various microfluidic platforms have been developed to enable the miniaturization, integration and automation of required assay. However, literature on the incorporation of piezoelectric quartz crystal (PQC) sensor with a microfluidic chip has seldom been found. Since our laboratory have capability in both areas, they can be utilized for microfluidic detection as described below. The acoustic sensing by PQC sensor depends on molecular interacting with immobilized receptors on the surface of a quartz crystal, giving rise to a concomitant modulation of the acoustic resonance of the crystal. This, in turn, results in a modulated electrical signal that can be analyzed using standard digital signal processing techniques. The signal indicates not only the presence of the analyte, but also the specificity and affinity for a surface-bound receptor. Various highly specific bio-molecules such as antibodies and nucleic acids can be used as specific sensing mat erial at the surface of PQC electrode for targeted compounds. However, the operations are expensive and require critically controlled working conditions, hence not suitable for direct environmental or biomedical monitoring. Recent ly, the molecular imprinting technology has been developed to provide an alternative method to prepare specific binding sites for given molecules in appropriate solid matrices. In this approach, the shape and functionality of a template can be transcribed onto microporous material s. The configuration of the functional groups in the template may be memorized within the matrix. Thus, the molecularly imprinted polymers (MIP) provide suitable coating material capable to mimic the recognition properties of these biomolecules while maintaining the stability and ruggedness during operation, which could increase the lifetime and durability of the sensing devices. Thus, in the present proposal, the MIP and PQC technologies are combined to fabricate suitable protein and sucrose imprinted sensing film on the surface of PQC electrode in determination of important proteins and sucrose in blood or beverage. |
| List of Research Outputs |
| Chen R. , Cheng G. , So M.H. , Wu J., Lu Z., Che C.M. and Sun H. , Bismuth Subcarbonate Nanoparticles Fabricated By Water-in-oil Microemulsion-assisted Hydrothermal Process Exhibit Anti-helicobacter Pylori Properties, Materials Research Bulletin . 2010, 45: 654-658. |
| Cheng T. , Li H. , Xia W. and Sun H. , Structure and function study of SlyD in Helicobacter pylori , 21st IUBMB and 12th FAOBMB International Congress of Biochemistry and Molecular Biology, Shanghai, Chi na, August 2-7 . 2009. |
| Cun S. and Sun H. , A zinc-binding site by negative selection induces metallodrug susceptibility of an essential chaperonin, Proceedings of the National Academy of Sciences, USA . 2010, 107: 4943-4948. |
| Du X. , Wang X. , Chan D.S.B. and Sun H. , Expression, purification and characterization of the N-terminal domain of the human copper transporter (hCtr1) , 14th International Conference on Biological Inorganic Chemistry, Nagoya, Japan, July 25-30 (published in J. Biol. Inorg. Chem. 2009, 14, Suppl1, P534) . 2009, 14. |
| Ge R. , Chu I.K. and Sun H. , Nuclear-based metallomics in metal-based drugs, "Advanced nuclear analytical techniques for metall omics and metalloproteomics" (Edited by C.Y. Chen, Z.F. Chai, YX Gao) . Royal Society of Chemistry, 2010, 265-298. |
| Guo W. , Lau K.M., Sun H. and Fung Y.S. , Microfluidic Chip-Capillary Electrophoresis for Emergency Onsite Biomedical Analysis, Separation Science . 2010, 2: 3-10. |
| Huang J. , Sun H. , Tanner J.A. and Watt R.M. , Determine the functions of the putative metal-binding domain of SARS-CoV helicase, Hong Kong Medical Journal . 2009, 15(5) Supplement: 6:15-16. |
| Qi S. , Sun H. and Huang J. , Expression and Purification of Mutated hpn Protein, and Studies of Function of Cystein Residues in hpn, 14th Research Postgraduate Symposium, December 2 & 3, 2009, The University of Hong Kong . 2009. |
| Qi S. , Sun H. and Huang J. , Expression and purification of mutated hpn protein and studies of cysteine residues in hpn, 14th International Conference on Biological Inorgani c Chemistry, Nagoya, Japan, July 25-30, 2009 (published in J. Biol Inorg Chem. 2009, 14, Suppl1, P606) . 2009. |
| Sun H. , Lau K.M. and Fung Y.S. , A New Capillary Electrophoresis Buffer For Determining Organic and Inorganic Anions in Electroplating Bath with Surfactant Additives, Journal of Chromatography A . 2010, 1217: 3244-3250. |
| Sun H. , Croucher Senior Research Fellow (2010-2011), Croucher Foundation . 2010. |
| Sun H. , Nie Z. and Fung Y.S. , Determination of binding capacity of albumin for bilirubin by Microfluidic chip-Capillary Electrophoresis based on insitu titration at a circular ferrofluid driven micromixer, Electrophoresis . 2010. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Development of Molecularly Imprinted Polymer Based Piezoelectric Quartz Crystal Biosensori , Extended Abstract of 12th International Symposium on Electroanalytical Chemistry (12th ISEC), Changchun, China, August 12-15, 2009 . Page 151. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Development of Molecularly Imprinted Polymer based Piezoelectric Quartz Crystal Biosensor, Conference proceeding of the The 12th International Symposium on Electroanalytical Chemistry, August 12-15, 2009, . 2009, 151. |
| Sun H. , Guest Professorship, Wuhan Institute of Technology . 2010. |
| Sun H. , Lau K.M. and Fung Y.S. , Hui Sun, Kwokman Lau and Yingsing Fung. A new capillary electrophoresis buffer for determining organic and inorganic anions in electroplating bath with surfactant additives, Journal of Chromatography A . 2010, 1217: 3244-3250. |
| Sun H. and Fung Y.S. , Nucleic Acid Based Piezoelectric Quartz Crystal Biosensor for Dectection of E. Coli , 12th International Symposium on Electroanalytical Chemistry (12th ISEC), Changchun, China, August 12-15, 2009 . 2009. |
| Sun H. and Fung Y.S. , Nucleic Acid Based Piezoelectric Quartz Crystal Bios ensor for Detection of E. coli, Extended Abstracts of 12th international Symposium on Electroanalytical Chemistry (12th ISEC), Changchun, China, August 12-15, 2009 . Page 20. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Nucleic Acid Based Piezoelectric Quartz Crystal Biosensor for Detection of E.coli , Conference Proceeding of The 12th International Symposium on Electroanalytical Chemistry, Changchun, China, August 12-15, 2009 . 20. |
| Sun H. , Albano D.R.B. and Fung Y.S. , Piezoelectric Quartz Crystal Biosensor for Detection of Protein Biomarker for Infective Disease, Conference proceeding of Biosensors 2010, 20th Anniversary World Congress on Biosensors, Glasgow, United Kingdom , May 28 to May 30, 2010 . P.1.10. |
| Sun H. , Rahula A.D. and Fung Y.S. , Piezoelectric Quartz Crystal Biosensor for Detection of Protein Biomarker for Infective Disease , Abstract, The 20th World Congress on Biosensors (Biosensors 2010), May 26-28, 2010, Glasgow, United Kingdom . 2010, P.1.10. |
| Sun X. , Baker H.M., Ge R. , Sun H. , He Q. and Baker E.N., Crystal structure and metal binding properties of the lipoprotein MtsA, responsible for iron transport in Streptococcus pyogenes , Biochemistry . 2009, 48: 6168-6190. |
| Tian Y., Hou X., Wen L., Guo W., Song Y., Sun H. , Wang Y., Jiang L. and Zhu D., A biomimetic zinc activated ion channel, Chemical Communication . 2010, 46: 1682-1684. |
| Wang X. , Du X. , Li H. , Chan D.S.B. and Sun H. , Effect of the N-terminal of the human high affinity copper transporter 1 (hCtr1) on cisplatin hydrolysis and uptake, 14th International Conference on Biological Inorganic Chemistry, Nagoya, Japan, July 25-30 (published in J. Biol. Inorg. Chem. 2009, 14, Suppl 1, P305) . 2009. |
| Wu Z.Y., Liu Q., Liang X., Yang X., Wang N.Y., Wang X. , Sun H. , Lu Y. and Guo ZJ , Reactivity of platinum-based antitumor drugs towards a Met- and His-rich 20mer peptide corresponding to the N-terminal domain of human copper transporter 1, Journal of Biological Inorganic Chemistry . 2009, 14: doi: 10.1007/s00775-009-0576-7. |
| Xia W. , Li H. , Sze K.H. and Sun H. , Structure of a nickel chaperone, HypA from Helicobacter pylori reveals two distinct metal binding sites, Journal of American Chemical Society . 2009, 131: 10031-10040. |
| Xia W. , Li H. , Sze K.H. and Sun H. , The Bifunctional Roles of Nickel Ions in Helicobacte r pylori [NiFe] - Hydrogenase Maturation Pathway, , Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic University, Hong Kong, April 24, 2010 . I-78. |
| Researcher : Sun J |
| List of Research Outputs |
| Kao P.Y.P. , Yang D. , Lau L.S. , Tsui H.W., Hu L. , Dai J. , Chan M.P. , Chan C.M. , Wang P. , Zheng B. , Sun J. , Huang J. , Madar J., Chen G. , Chen H. , Guan Y. and Yuen K.Y. , Identification of Influenza a Nucleoprotein as an Antiviral Target, Nature Biotechnology . 2010, 28: 600-608. |
| Sun J. , Computer-Aided Drug Design for Influenza A Virus (PhD Thesis) . 2010. |
| Researcher : Sun J |
| List of Research Outputs |
| Kao P.Y.P. , Yang D. , Lau L.S. , Tsui H.W., Hu L. , Dai J. , Chan M.P. , Chan C.M. , Wang P. , Zheng B. , Sun J. , Huang J. , Madar J., Chen G. , Chen H. , Guan Y. and Yuen K.Y. , Identification of Influenza a Nucleoprotein as an Antiviral Target, Nature Biotechnology . 2010, 28: 600-608. |
| Sun J. , Computer-Aided Drug Design for Influenza A Virus (PhD Thesis) . 2010. |
| Researcher : Sun RWY |
| Project Title: | Dual Cytotoxic and Anti-Angiogenic Properties of Metal-Based Complexes |
| Investigator(s): | Sun RWY |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 10/2009 |
| Abstract: |
| Despite the widespread clinical use of cisplatin and its derivatives for anti-cancer treatment, these cytotoxic platinum(II) complexes still suffer from severe toxic side effects and acquired drug resistance. Thus there are continuing worldwide efforts to search for new bioactive metal complexes including that of gold and ruthenium as modern therapeutics. The major anti-cancer mechanism of gold(III) and ruthenium complex es are either cytotoxic (induce cell death) or anti-angiogenic (suppress tumor growth by inhibiting blood vessel formation to tumor or cancer cell). Nevertheless, reports on anti-cancer agents having the dual cytotoxic and anti-an giogenic activities are sparse in the literature (Nat. Rev. Cancer 2004, 4, 423). Bioactive compounds with dual cytotoxic and anti-angiogenic properties can enhance anti-cancer potency by reducing the acquired-drug resistance and systematic toxicities generated by using either a cytotoxic or an anti-angiogenic agent alone (J. Cli n. Oncol., 2005, 23, 1295). It has also been demonstrated that combination of a cytotoxic agents employed in transarterial chemoembolization (TACE) with an anti-angiogenic/metasta tic agent can significantly prolong survival of patients having advanced hepatocellular carcinoma (HCC). In this regard, we are interested to investigate whether cytotoxic gold(III) and ruthenium complexes can also have significant anti-angiogenic activities at their sub-cytotoxic levels. For the past few years, The PI has actively been participating in the discovery of novel kinds of anti-cancer agents. A gold(III) porphyrin complex [Au(TPP)]Cl (gold-1a) has been identified to display promising in vitro and in vivo anti-cancer activities toward various kinds of cancer (Coord. Ch em. Rev., 2009, 253, 182; Chem. Commun. 2003, 1718). By means of modern biochemical technology including proteomics and cDNA array, their action mechanism has been evaluated (Cancer Res, 2005, 65, 11553; Int. J. Cancer, 2006, 118, 1527; Int. J. Cancer, 2009, 124, 1971; Cancer, 2009, in press). By MTT and tube formation assay, previously we observed that some gold(III) and ruthe nium complexes exhibit significant anti-angiogenic activities at their sub-cytotoxic level. In this application, we aim to validate previous results and pioneer the systematic study on the dual cytotoxic and anti-angiogenic properties of gold(III) and ruthenium complex by evaluati ng their anti-angiogenic activities at their sub-cytotoxic levels using various kinds of biochemical techniques. |
| List of Research Outputs |
| Chow H.M. , Sun R.W.Y. , Lam J.B.B. , Li C.K.L. , Xu A. , Abagyan R., Wang Y. and Che C.M. , A Gold(III) Porphyrin Complex with Antitumor Properties Targets the Wnt/ b -catenin Pathway, Cancer Research . 2010, 70: 329-337. |
| Lee P.Y. , Zhu Y. , Sun R.W.Y. , Hao W. , Liu X. , Che C.M. and Wong K.K.Y. , A safe and efficient lipidic nanoparticle carrier of gold porphryin for the treatment of neuroblastoma, The 3rd European Conference for Clinical Nanomedicine, Basel, Switzerland, 10-12 May 2010 . |
| Lee P.Y. , Zhu Y. , Yan J., Sun R.W.Y. , Hao W. , Liu X.L., Che C.M. and Wong K.K.Y. , The cytotoxic effects of lipidic formulated gold-porphyrin nanoparticles for the treatment of neuroblastoma, Nanotechnology, Science and Applications . 2010, 3: 23-28. |
| Li W., Xie Y. , Sun R.W.Y. , Liu Q., Young J., Yu W.Y. , Che C.M. , Tam P.K.H. and Ren Y. , Inhibition of Akt sensitises neuroblastoma cells to gold(III) porphyrin 1a, a novel antitumour drug induced apoptosis and growth inhibition, British Journal of Cancer . 2009, 101(2): 342-349. |
| Sun R.W.Y. , Anti-Cancer Gold(III) Porphyrin Complex, Outstanding Poster Award (6th National Conference on Coordination Chemistry (cum International Symposi um on Coordination Chemistry) on 6th – 9th July 2009. The University of Hong Kong, Hong Kong . 2009. |
| Sun R.W.Y. , Ng F.Y. , Wong E.L.M. , Zhang J. , Chui S.Y. , Shek L. , Lau T.C. and Che C.M. , Dual anti-angiogenic and cytotoxic properties of ruthenium(III) complexes containing pyrazolato and/or pyrazole ligands , Dalton Transactions . 2009, 10712-10716. |
| Sun R.W.Y. , Li C.K.L. , Ma D.L. , Yan J. , Lok C.N. , Leung C.H. , Zhu N. and Che C.M. , Stable anticancer gold(III)-porphyrin complexes: effects of porphyrin structure, Chemistry - A European Journal . 2010, 16: 3097-3113. |
| Tu S.P., Sun R.W.Y. , Lin M.C. , Cui J.T., Zou B. , Gu Q. , Kung H.F., Che C.M. and Wong B.C.Y. , Gold (III) Porphyrin Complexes Induce Apoptosis and Cell Cycle Arrest and Inhibit Tumor Growth in Colon Cancer, Cancer . 2009, 115(19): 4459-4469. |
| Yan J. , Chow L.F. , Leung C.H. , Sun R.W.Y. , Ma D.L. and Che C.M. , Cyclometalated gold(III) complexes with N-heterocyclic carbene ligands as topoisomerase I poisons , Chemical Communications . Britain, Royal Chemical Society, 2010, 46: 3893 - 3895. |
| Researcher : Sun X |
| List of Research Outputs |
| Sun X. , Baker H.M., Ge R. , Sun H. , He Q. and Baker E.N., Crystal structure and metal binding properties of the lipoprotein MtsA, responsible for iron transport in Streptococcus pyogenes , Biochemistry . 2009, 48: 6168-6190. |
| Researcher : Sun Z |
| List of Research Outputs |
| Yang D. , Sun Z. , Peng T. , Wang L.H., Shen J. , Chen Y. and Tam P.K.H. , Synthetic fluorescent probes for imaging of peroxynitr ite and hypochlorous acid in living cells, Methods Mol Biol. . 2010, 591: 93-103. |
| Yang D. , Sun Z. , Peng T. , Wang H.L., Shen J.G., Chen Y. and Tam P.K.H. , Synthetic fluorescent probes for imaging of peroxynitrite and hypochlorous acid in living cells, Methods in Molecular Biology . 2010, 591: 93-103. |
| Researcher : Sy LK |
| Project Title: | 5th International Symposium on Autophagy Timosaponin A-III induces cytoprotective autophagy |
| Investigator(s): | Sy LK |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 09/2009 |
| Completion Date: | 09/2009 |
| Abstract: |
| N/A |
| Researcher : Sze J |
| List of Research Outputs |
| An X. , Ng S.M. , Xie D., Zeng Y.X., Sze J. , Wang J. , Chen Y.C., Chow B.K.C. , Lu G., Poon W.S., Kung H.F., Wong B.C.Y. and Lin M.C. , Functional characterisation of cell cycle-related kinase (CCRK) in colorectal cancer carcinogenesis. , European Journal of Cancer . 2010, 46: 1752-1761. |
| Wu G.Q., Xie D., Yang G.F., Liao Y.J., Mai S.J., Deng H.X., Sze J. , Guan X.Y., Zeng Y.X., Lin M.C. and Kung H.F., Cell Cycle-Related Kinase Supports Ovarian Carcinoma Cell Proliferation via Regulation of Cyclin D1 and is a Predictor of Outcome in Ovarian Carcinoma Patients, International Journal of Cancer . 2009, 125(11): 2631-42. |
| Xia H. , Ng S.M. , Jiang S.S., Cheung K.C. , Sze J. , Bian X.W., Kung H.F. and Lin M.C. , miR-200a-mediated Downregulation of ZEB2 and CTNNB1 Differentially Inhibits Nasopharyngeal Carcinoma Cell Growth, Migration and Invasion, Biochemical and Biophysical Research Communications . 2009, 391(1): 535-541. |
| Zheng B. , Sze J. , Cheung K.C. , Lin M.C. and Kung H.F., Super Interferons for the Treatment of Bird Flu, Tri-Society Annual Conference 2009 of the Society for Leukocyte Biology, International Cytokine Society, & International Society for Interferon and Cytokine Research; Portugal; 17-21 October, 2009. . 2009. |
| Researcher : Sze KH |
| Project Title: | XXIInd International Conference on Magnetic Resonance in Biological Systems (ICMRBS 2006) Backbone Dynamics and Solution Structure of a Thermophilic Acylphosphatase from Pyrococcus Horikoshii by NMR Spectroscopy |
| Investigator(s): | Sze KH |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 08/2006 |
| Abstract: |
| N/A |
| Project Title: | Structural and functional studie s of the SWIRM domain in Lysine-specific Demethylase 1 (LSD1) |
| Investigator(s): | Sze KH |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2007 |
| Completion Date: | 12/2009 |
| Abstract: |
| (1) Determination of the solution structure and backbone dynamics of swirm domain in LSD1; (2) characteriza tion of the functional role of swirm domain in LSD1. |
| Project Title: | Structure-function study of XIAP-Associated Factor 1 (XAF1) structure determinations of XAF1 and its complex with X-Linked Inhibitor of Apoptosis Protein (XIAP) by multi-dimensional NMR spectroscopy |
| Investigator(s): | Sze KH, Wong BCY |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 11/2008 |
| Abstract: |
| (1) To delineate the domain architecture of XAF1 and to determine the solution structure of each identified XAF1 domain via NMR spectroscopy; (2) To characterize the interaction of each XAF1 domain with XIAP in order to identify the XIAP binding domain/s in XAF1; (3)To map and characterize the corresponding XAF1 binding domain/s in XIAP; (4) To determine the structure of interaction complex between characterized XAF1 and XIAP binding domains via NMR spectroscopy. |
| Project Title: | Structure-function study of ubiquitin C-terminal hydrolase L1 (UCH-L1) |
| Investigator(s): | Sze KH |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 04/2009 |
| Completion Date: | 03/2010 |
| Abstract: |
| Parkinson’s disease (PD) and Alzheimer’s disease (AD), the most common neurodegenerative diseases, are caused by both genetic and environmental factors. The mechanism of protein metabolism in living cells through the proteasome system, ubiquitination, and deubiquitination is a biologically important process to maintain the health of the cells. In particular, deubiquitination is considered essential for negative regulation of proteolysis and for recycling of ubiquitin from polyubiquitin chains. Ubiquitin carboxy-terminal hydrolase L1 (UCH-L 1), a multifunctional 24.8 kDa protein, is one of the most abundant proteins in the brain (1–2% of the total soluble protein) but is almost absent from other tissues (1). Thus, its role in neuronal cell function/dysfunction was predicted. Indeed, the lack of UCH-L1 expression in mice results in gracile axonal dystrophy (gad) pheno type (2). Down-regulation and extensive oxidative modification of UCH-L1 have been observed in the brains of AD as well as PD patients (3-5). Moreover, administration of UCH-L1 was shown to alleviate the beta-amyloid-induced synaptic dysfunction and memory loss associated with a mouse model of AD (6). Interestingly, an isoleucine 93 to methionine amino acid mutation (I93M) of UCH-L1 was identified as a cause of autosomal dominant PD (7). On the contrary, a polymorphism that results in the amino acid substitution of serine 18 to tyrosine in UCH-L1 (S18Y) was linked to decreased susceptibility to PD in some populations (8-16) Taken all of these aspects together, the precise regulation of UCH-L1 is essential for neurons to survive and to maintain their proper function. It is also of interest to note that abnormal overexpression of UCH-L1 has been shown to correlate with many primary lung tumors, tumor cell lines and colorectal cancer (17-20). The assumption that each enzyme expresses a single enzymatic activity in vivo is challenged by the linkage of UCH-L1 neuronal enzyme to PD. UCH-L1, especially those variants linked to higher susceptibility to PD causes the accumulation of alpha-synuclein in cultured cells, which is an effect that cannot be explained by its originally recognize d deubiquitinating hydrolase activity. UCH-L1 was later shown to exhibit an unexpected ubiquitin ligase (21) and a mono-ubiquitin stabilizer (22) activities. However, the S18Y polymorphic variant of UCH-L1 has shown reduced ligase activity but comparable hydrolase activity as the wild-type enzyme. Thus, the balance between ligase activity as well as the hydrolase activity of UCH-L1 may play an important role in regulating the proteasomal protein degradation in the brain. Furthermore, since the amino acid sequence of UCH-L1 is similar to that of other ubiquitin C-terminal hydrolases, including the ubiquitously expressed UCH-L3, which appear to be unconnected to neurodegenerative disease, the structure of UCH-L1 and the effects of disease associated mutation s on the structure and function of UCH-L1 are of considerable interest and importance. Indeed, a recent small-angle neutron scattering study indicated that the I93M mutation promotes ellipsodial deformation by a decrease of the beta-turn contents compared with wild type UCH-L1 whe reas the S18Y mutation recovers the globularity of the protein by an increase of beta-turns (23). The fact that UCH-L1 is specifically expressed in neurons in large amount suggests that UCH-L1 has an important functional role in the biology of the mammalian central nervous system. Association of UCH-L1 with PD and cancer has sparked great interest in this enzyme, yet many of its important properties have not been determined. We are interested in understanding the role of UCH-L 1 in neurodegenration in general. In this study, we aim at addressing the following main questions: 1. What are the solutions structures of the wild type UCH-L1 and its I93M and S18Y mutants? 2. How does the I93M mutation create the reported ellipsodial deformation and how does the S18Y mutation recover the globularity of the protein? 3. Is there any correlation between mutation induced structure changes with the risk of Parkinson's disease? References: 1. Wilkinson, K. D., et al., (1989) Science 246, 670–673. 2. Saigoh, K., et al., 1999 Nat. Genet. 23, 47–51. 3. Castegna, et al., 2002 J. Neurochem. 82, 1524–1532. 4. Choi, J., et al., 2004. J. Biol. Chem. 279, 13256–13264. 5. Butterfield, D.A., et al., 2006. J. Alzheimers Dis. 10, 391–397. 6. Gong, B., et al., 2006. Cell 126, 775–788. 7. Leroy, E., et al., 1998. Nature 395, 451–452. 8. Maraganore, D.M., et al., 1999. Neurology 53, 1858–186 0. 9. Wintermeyer, P., et al., 2000. Neuroreport 11, 2079–2082. 10. Wang, J., et al., 2002. Mov. Disord. 17, 767–771. 11. Elbaz, A., et al., 2003. Mov. Disord. 18, 130–137. 12. Toda, T., et al., 2003. J. Neurol. 250 (Suppl. 3), III40–III43. 13. Maraganore, D.M., et al., 2004. Ann. Neurol. 55, 512–521. 14. Facheris, M., et al., 2005 Neurosci. Lett. 381, 131–134. 15. Tan, E.K., et al., 2006. Mov. Disord. 21, 1765–1768. 16. Carmine Belin, A., et al., 2007. Parkinsonism Relat. Disord. 13, 295–298. 17. Hibi, K., et al., 1999. Am. J. Pathol. 155, 711–715. 18. Sasaki, H., et al., 2001. Jpn. J. Clin. Oncol. 31, 532–535. 19. Hibi, K., et al., 1998. Cancer Res. 58, 5690–5694. 20. Yamazaki, T., et al., 2002. Clin. Cancer Res. 8, 192–195. 21. Liu, Y., et al., 2002. Cell 111, 209–218. 22. Osaka, H., et al., 2003. Hum. Mol. Genet. 12, 1945–1958. 23. Naito, S., et al., 2006. Biochem. Biophys. Res. Commun. 339, 717–725. |
| Project Title: | Structure-function study of ubiquitin C-terminal hydrolase L1 (UCH-L1) by NMR Spectroscopy Insights into structure changes induced by mutations associated with the risk of Parkinsons disease' |
| Investigator(s): | Sze KH |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 07/2009 |
| Abstract: |
| 1) What are the solutions structures of the wild type UCH-L1 and its I93M and S18Y mutants? 2) How does the I93M mutation create the reported ellipsodial deformation and how does the S18Y mutation recover the globularity of the protein? 3) Is there any correlation between mutation induced structure changes with the risk of Parkinson's disease? |
| Project Title: | Third Asia-Pacific NMR Symposium X-linked inhibitor of apoptosis protein (XIAP) catches ubiquitin: Determination of the solution structure of ubiquitin-associated domain of XIAP and Mapping its interaction sites with ubiquitin Solution Structure of an Unusual 28 kDa Active Mutant of Maize Ribosome-Inactivating Protein (MOD) and Its Interaction |
| Investigator(s): | Sze KH |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 10/2009 |
| Completion Date: | 10/2009 |
| Abstract: |
| N/A |
| List of Research Outputs |
| Chen X.L., Guo Z.F., Lai P.M. , Sze K.H. and Guo Z.G., Characterization of a Nanaketide Precursor in Biosynthesis of the Nine-Membered Enediyne Core of the Antitumor Antiotic C-1027, Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic University, Hong Kong, April 24, 2010. . 2010, O-67. |
| Cheng K.W. , Zeng X. , Tang Y.S., Wu J. , Liu Z.W., Sze K.H. , Chu I.K. , Chen S.F. and Wang M. , Inhibitory Mechanism of Naringenin against Carcinogenic Acrylamide Formation and Non-enzymatic Browning in Maillard Model Reactions , Chemical Research in Toxicology . 2009, 22: 1483-1489. |
| Cho C.K.L. , Tse M.K. , Wong B.C.Y. and Sze K.H. , Structure Determination of the CTB by NMR Spectroscopy, Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic University, Hong Kong, April 24, 2010. . 2010, O-99. |
| Hui S.K. , Tse M.K. , Yang Y. and Sze K.H. , Backbone and Side-chain 1 H, 13 C and 15 N Assignments of the Ubiquitin-associated Domain of Human X-linked Inhibitor of Apoptosis Prote in , Biomol. NMR Assignments . 2010, 4: 13-15. |
| Hui S.K. , Tse M.K. , Wong B.C.Y. and Sze K.H. , Structural and Interaction Study of Ubiquitin-associated (UBA) Domain of XIAP Protein by NMR Spectroscopy, Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic University, Hong Kong, April 24, 2010. . 2010, O-96. |
| Hui S.K. , Tse M.K. , Zhou B., Wong B.C.Y. and Sze K.H. , X-linked Inhibitor of Apoptosis Protein (XIAP) Catches Ubiquitin: Determination of the Solution Structure of Ubiquitin-Associated Domain of Xiap and Mapping its Interaction Sites With Ubiquitin, The Third Asia-Pacific NMR Symposium, Jeju Island , Korea, October 25-28, 2009 . PD18, p220. |
| Liang H.C., Li X.Z., Yang Y. and Sze K.H. , Comparison Of The Degradations Of Diphenamid By Homogeneous Photolysis And Heterogeneous Photocatalysis In Aqueous Solution, Chemosphere . 2010, 80: 366-374. |
| Lo K.C. , Zhu G. and Sze K.H. , Study on the Interaction between DNA-binding Domain (DBD) of Human Androgen Receptor (AR) and SWIRM Domain of Lysine-specific Demethylase 1 (LSD1), Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic University, Hong Kong, April 24, 2010. . 2010, O-97. |
| Song A.X., Zhou C.J., Sze K.H. and Hu H.Y., Solution Structure of the N-terminal Domain of DC-UbP/UBTD2 and its Interaction with Ubiquitin , Protein Science . 2010, 19: 1104-1109. |
| Sze K.H. , Recent advancements in Biomolecular NMR spectroscopy and Structure-Function study of an Unusual 28 kDa Ribosome-Inactivating Protein (MOD) and Its Interaction with the Ribosomal Stalk Protein P2 , Department of Biochemistry, University of Hong Kong, January 29, 2010. . 2010. |
| Sze K.H. , Shanghai Institute of Materia Medical, Chinese Academy of Sciences, November 23, 2009, Structure-function Study of XIAP: Domain Dissection of Human XIAP Associated Factor 1 Protein and Determina tion of the Solution Structure of Ubiquitin-associated Domain of XIAP . 2009. |
| Sze K.H. , Structure-function Study of XIAP: Domain Dissection of Human XIAP Associated factor 1 Protein and Determ ination of the Solution Structure of Ubiquitin-associated Domain of XIAP, Institute of Biochemistry and Cell Biology, Shangh ai Institutes for Biological Sciences, November 24, 2009 . 2009. |
| Sze K.H. , X-linked Inhibitor ofApoptosis Protein (XIAP) Catches Ubiquitin: Determination Of The Solution Structure of Ubiquitin-associated Domain of Xiap and Mapping its Interaction Sites with Ubiquitin” , The Third Asia-Pacific NMR Symposium, Jeju Island, Korea, October 25-28, 2009. . 2009. |
| Tse H.S. , Hu Y.H. and Sze K.H. , Structure and Dynamics Studies of Human Ubiquitin Carboxyl Terminall Hydrolase by NMR Spectroscopy, Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic University, Hong Kong, April 24, 2010. . 2010, O-98. |
| Xia W. , Li H. , Sze K.H. and Sun H. , Structure of a nickel chaperone, HypA from Helicobacter pylori reveals two distinct metal binding sites, Journal of American Chemical Society . 2009, 131: 10031-10040. |
| Xia W. , Li H. , Sze K.H. and Sun H. , The Bifunctional Roles of Nickel Ions in Helicobacter pylori [NiFe] - Hydrogenase Maturation Pathway, , Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic University, Hong Kong, April 24, 2010 . I-78. |
| Yang Y. , Mak A.N.S., Shaw P.C. and Sze K.H. , Solution Structure of an Active Mutant of Maize Ribo some-Inactivating Protein (MOD) and Its Interaction with the Ribosomal Stalk Protein P2, Journal of Molecular Biology . 2010, 395: 897-907. |
| Zeng X. , Kong P.W. , Cheng K.W. , Du Y. , Tang Y.S. , Chu I.K. , Lo C.S.C. , Sze K.H. , Chen F. and Wang M. , Direct Trapping of Acrylamide as a Key Mechanism for Niacin's Inhibitory Activity in Carcinogenic Acrylamide Formation, Chemical Research in Toxicology . 2010, 23: 802-807. |
| Zhu Q. , Zheng Z. , Cheng K.W. , Wu J. , Zhang S., Tang Y.S., Sze K.H. , Chen J., Chen S.F. and Wang M. , Natural Polyphenols as Direct Trapping Agents of Lipid Peroxidation-derived Acrolein and 4-Hydroxy-trans-2-no nenal, Chemical Research in Toxicology . 2009, 22: 1721-1727. |
| Researcher : Sze KL |
| List of Research Outputs |
| Sze K.L. and Fung Y.S. , Abstract of Microfluidic Capillary Electrophoresis for the Determination of Trace Metals in Milk, 8th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2008), Kaohsiung, Taiwan , November 2-5, 2008 . 2009, P01-03, pp97. |
| Sze K.L. and Fung Y.S. , Capillary Electrophoresis for Trace Metal Determination in Milk, Abstract of the 9th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P4-09: pp237. |
| Sze K.L. , Electrophoretic Methodologies for the Determinations of Minerals and Trace Elements (MPhil Thesis) . 2009. |
| Researcher : Sze-To L |
| List of Research Outputs |
| Guo J.F., Wang X.T., Wang B.W., Xu G.C., Gao S., Sze-To L. , Wong W.T. , Wong W.Y. and Lau T.C., One-Dimensional Ferromagnetically Coupled Bimetallic Chains Constructed with trans -[Ru(acac) 2 (CN) 2 ] - :Syntheses, Structures, Magnetic Properties, and Density Functional Theoretical Study, Chemistry - A European Journal . 2010, 16: 3524-3535. |
| Law G.L. , Wong K.L., Lau K.K., Sze-To L. , Tanner P.A., Kuo F. and Wong W.T., Nonlinear Optical Activity in Dipolar Organic-lantha nide Complexes, Journal of Material Chemistry . 2010, 20: 4074-4079. |
| Researcher : Sze-To L |
| List of Research Outputs |
| Guo J.F., Wang X.T., Wang B.W., Xu G.C., Gao S., Sze-To L. , Wong W.T. , Wong W.Y. and Lau T.C., One-Dimensional Ferromagnetically Coupled Bimetallic Chains Constructed with trans -[Ru(acac) 2 (CN) 2 ] - :Syntheses, Structures, Magnetic Properties, and Density Functional Theoretical Study, Chemistry - A European Journal . 2010, 16: 3524-3535. |
| Law G.L. , Wong K.L., Lau K.K., Sze-To L. , Tanner P.A., Kuo F. and Wong W.T., Nonlinear Optical Activity in Dipolar Organic-lanthanide Complexes, Journal of Material Chemistry . 2010, 20: 4074-4079. |
| Researcher : Tam AYY |
| List of Research Outputs |
| Li Y.G., Wong M.C. , Tam A.Y.Y. , Wu L.X. and Yam V.W.W. , Thermo- and acid-responsive photochromic spironaphthoxa zine-containing organogelators, Chemistry - A European Journal . 2010, 8690-8698. |
| Tam A.Y.Y. , Wong M.C. and Yam V.W.W. , Influence of Counter-Anion on the Chiral Supramolecular Assembly of Alkynylplatinum(II) Terpyridyl Metallogels that are Stabilized by Pt···Pt and p - p Stacking Interactions, 5th International Symposium on Macrocyclic and Supramolecular Chemistry . 2010. |
| Tam A.Y.Y. , Wong M.C. , Zhu N. , Wang G. and Yam V.W.W. , Luminescent Alkynylplatinum(II) Terpyridyl Metallogels Stabilized by Pt∙∙∙Pt, p - p , and Hydrophobic-Hydophobic Interactions , Langmuir . 2009, 25: 8685-8695. |
| Researcher : Tam WY |
| List of Research Outputs |
| Chan W.K. , Mak S.K. , Tam W.Y. and Leung Q.Y. , Functional Polymers For Photovoltaic Applications, The 9th International Symposium on Advanced Organic Photonics (ISAOP-9), Bunratty, Ireland . 2009. |
| Mak S.K. , Wong H.L. , Leung Q.Y. , Tam W.Y. , Chan W.K. and Djurisic A. , The use of sublimable chlorotricarbonyl bis(phenylimino)a cenaphthene rhenium(I) complexes as photosensitizers in bulk-heterojunction photovoltaic devices, Journal of Organometallic Chemistry . ELSEVIER SCIENCE SA, 2009, 694: 2770-2776. |
| Tam W.Y. , Design, Synthesis and Functionalization of Luminescent Alkynyplatinum(II) Complexes of Tridentate N -Donor Ligands as Building Blocks for metallogelati on and Supramolecular Assembly (PhD Thesis) . 2009. |
| Tam W.Y. , Functional Diblock Copolymers for Nanofabrications and Photovoltaic Applications (PhD Thesis) . 2010. |
| Researcher : Tam WY |
| List of Research Outputs |
| Chan W.K. , Mak S.K. , Tam W.Y. and Leung Q.Y. , Functional Polymers For Photovoltaic Applications, The 9th International Symposium on Advanced Organic Photonics (ISAOP-9), Bunratty, Ireland . 2009. |
| Mak S.K. , Wong H.L. , Leung Q.Y. , Tam W.Y. , Chan W.K. and Djurisic A. , The use of sublimable chlorotricarbonyl bis(phenylimino)acenaphthene rhenium(I) complexes as photosensitizers in bulk-heter ojunction photovoltaic devices, Journal of Organometallic Chemistry . ELSEVIER SCIENCE SA, 2009, 694: 2770-2776. |
| Tam W.Y. , Design, Synthesis and Functionalization of Luminescent Alkynyplatinum(II) Complexes of Tridentate N -Donor Ligands as Building Blocks for metallogelation and Supramolecular Assembly (PhD Thesis) . 2009. |
| Tam W.Y. , Functional Diblock Copolymers for Nanofabrications and Photovoltaic Applications (PhD Thesis) . 2010. |
| Researcher : Tam YY |
| List of Research Outputs |
| Tam Y.Y. , Wong M.C. , Zhu N. and Yam V.W.W. , Luminescent Metallogel of Alkynylplatinum(II) Terpyridyl Complexes: Interplay of Metal ... Metal, p - p and Hydrophobic-Hydrophobic Interactions on Gel Formation, , The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry ) Hong Kong, P.R. China, July 6-9, 2009 . P216. |
| Researcher : Tang G |
| List of Research Outputs |
| Yao H. , Ng S.M. , Tang G. , Kung H.F. and Lin M.C. , Development of a Low-toxicity and High-efficiency Polymeric Nanoparticle for Gene Delivery, 2009 International Society for Cell & Gene Therapy of Cancer; Cork, Ireland; 2-4 September, 2009. . 2009. |
| Yao H. , Ng S.M. , Tucker W.O. , Tsang Y.K.T. , Man K. , Wang X.M., Chow B.K.C. , Kung H.F., Tang G. and Lin M.C. , The gene transfection efficiency of a folate-PEI600-cyclodextrin nanopolymer, Biomaterials . 2009, 30(29): 5793-5803. |
| Researcher : Tang HW |
| List of Research Outputs |
| Tang H.W. , Lu W. , Che C.M. and Ng K.M. , Double Imaging of Latent Fingerprints by Gold Nanoparticles-Assisted Imaging Mass Spectrometry , The 1st Asian & Oceanic Mass Spectrometry Conference, at Tsukuba International Congress Center, Tsukuba, Japan . 2010. |
| Tang H.W. , Lu W. , Che C.M. and Ng K.M. , Gold Nanoparticles and Imaging Mass Spectrometry: Double Imaging of Latent Fingerprints, Analytical Chemistry . 2010, 82: 1589–1593. |
| Researcher : Tang YS |
| List of Research Outputs |
| Cheng K.W. , Zeng X. , Tang Y.S. , Wu J. , Liu Z.W., Sze K.H. , Chu I.K. , Chen S.F. and Wang M. , Inhibitory Mechanism of Naringenin against Carcinogenic Acrylamide Formation and Non-enzymatic Browning in Maillard Model Reactions , Chemical Research in Toxicology . 2009, 22: 1483-1489. |
| Zeng X. , Kong P.W. , Cheng K.W. , Du Y. , Tang Y.S. , Chu I.K. , Lo C.S.C. , Sze K.H. , Chen F. and Wang M. , Direct Trapping of Acrylamide as a Key Mechanism for Niacin's Inhibitory Activity in Carcinogenic Acrylamide Formation, Chemical Research in Toxicology . 2010, 23: 802-807. |
| Researcher : Tao CH |
| List of Research Outputs |
| Chan K.M.C. , Tao C.H. , Tam H.L., Zhu N. , Yam V.W.W. and Cheah K.W., Synthesis, Characterization, Luminescence and Non-linear Optical (NLO) Properties of Oxadiazole- and Truxene-Containin g Platinum(II) Alkynyl Complexes with Donor-Acceptor Functionalities, The 42 nd International Union of Pure and Applied Chemistry (IUPAC) Congress, Glasgow, UK, August 2-7, 2009 . P701_46. |
| Chan K.M.C. , Tao C.H. , Tam H.L., Zhu N. , Yam V.W.W. and Cheah K.W., Synthesis, Characterization, Luminescence and Non-linear Optical Properties of Oxadiazole- and Truxene-contai ning Platinum(II) Alkynyl Complexes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P213. |
| Tao C.H. and Yam V.W.W. , Branched Carbon-Rich Luminescent Multinuclear Platinum(II) and Palladium(II) Alkynyl Complexes With Phosphine Ligands, Journal of Photochemistry and Photobiology C: Photoc hemistry Reviews . 2009, 10: 130-140. |
| Tao C.H. , Zhu N. and Yam V.W.W. , Synthesis, Characterisation and Luminescence Properties of Carbazole-Containing Platinum(II) and Palladium(II) Alkynyl Complexes (invited article), Journal of Photochemistry and Photobiology A: Chemistry . 2009, 207: 94-101. |
| Yam V.W.W. , Song H. , Chan T.W. , Zhu N. , Tao C.H. , Wong M.C. and Wu L.X., Synthesis, Characterization, Ion-Binding Properties, and Fluorescence Resonance Energy Transfer Behavior of Rhenium(I) Complexes Containing a Coumarin-Appended 2,2′-Bipyridine, Journal of Physical Chemistry C . 2009, 113: 11674-11682. |
| Yin Z.D., Tao C.H. , Wong M.C. , Yam V.W.W. and Wu L.X., A Novel Bodipy-based Probe and its Magnesium Ion-responsive Spectra, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P211. |
| Researcher : Ting SW |
| List of Research Outputs |
| Chan G.K.Y. , Li F. , Ting S.W. and Lam Y.L. , Mesoporous Carbons as Electrode Materials for Capacitors and Fuel Cells, 4th Asian Conference on Electrochemical Power Sources, Taipei, Taiwan, October 9-11, 2009 . |
| Chan G.K.Y. , van der Laak N.K. , Li F. , Lam Y.L. , Ting S.W. and Yang C. , Multi-scale Structuring of Composite Electrode Materials for Fuel Cells and Energy Applications, 2nd IWNA International Workshop on Nanotechnology and Application, Vung Tau, Vietnam, November 12-14, 2009 . 2009. |
| Li F. , van der Laak N.K . , Ting S.W. and Chan G.K.Y. , Varying Carbon Structures Templated From Kit-6 for Optimum Electrochemical Capacitance , Electrochimica Acta . 2010, 55: 2817-2823. |
| Ting S.W. , Cheng S. , Tsang K.Y. , van der Laak N.K. and Chan G.K.Y. , Low Activation Energy Dehydrogenation of Aqueous Formic acid on Platinum–ruthenium–bismuth Oxide at Near Ambient Temperature and Pressurew, Chemical Communications . 2009, 47: 7333-7335. |
| Researcher : Tong SM |
| Project Title: | High-valent iron porphyrins |
| Investigator(s): | Tong SM, Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 11/2004 |
| Abstract: |
| To investigate if dioxoiron (VI) porphyrin complex participates in the biological cycles of oxygen activat ion. |
| List of Research Outputs |
| Tong S.M. and Che C.M. , Emissive or Nonemissive? A Theoretical Analysis of the Phosphorescence Efficiencies of Cyclometalated Platinum(II) Complexes , Chemistry -- A Europe Journal . 2009, 15: 7225-7237. |
| Tong S.M. , Law Y.C. , Kui C.F. , Zhu N. , Leung K.H., Phillips D.L. and Che C.M. , Ligand-to-Ligand Charge-Transfer Transitions of Platinum(II) Complexes with Arylacetylide Ligands with Different Chain Lengths: Spectroscopic Characterization, Effect of Molecular Conformations, and Density Functional Theory Calculations, Chemistry - A European Journal . 2010, 16: 6540-6554. |
| Tong S.M. , Kui C.F. , Chao H.Y., Zhu N. and Che C.M. , The 3 [ n d s *( n +1)p s } Emissions of Linear Silver(I) and Gold(I) Chains with Bridging Phosphine Ligands, Chemistry - A European Journal . 2009, 2009: 10777-10789. |
| Tsui W.M. , Huang J.S. , Tong S.M. , Kui C.F. , Che C.M. and Zhu N. , Quinoneimido Complexes of a Metalloporphyrin: Isolation, X-ray Crystal Structures, and DFT Calculations, Chemistry - A Asian Journal . 2010, 5: 759-763. |
| Researcher : Toy PH |
| Project Title: | Gordon Research Conference on Green Chemistry Organocatalytic Mitsunobu Reactions |
| Investigator(s): | Toy PH |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 08/2006 |
| Abstract: |
| N/A |
| Project Title: | Polymer-supported phosphine and arsines as reagents, ligands and organic catalysts |
| Investigator(s): | Toy PH |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 10/2006 |
| Completion Date: | 09/2009 |
| Abstract: |
| (1) To synthesize and evaluate both soluble and insoluble polystyrene-supported phosphines and arsines for use as recyclable ligands in palladium catalyzed cross-coupling and platinum catalyzed alkyne boration reactions, and as nucleophilic reagents and catalysts. (2) To synthesize and evaluate chiral arsine oxides as catalysts for asymmetric alkene epoxidation reaction s using hydrogen peroxide as the stoichiometric oxidant and then to immobilize these compounds onto water compatible matricies so that they can be recovered and reused. |
| Project Title: | Development and Optimization of Catalytic Versions of the Mitsunobu Reaction |
| Investigator(s): | Toy PH |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 09/2007 |
| Abstract: |
| To refine the our previously reported catalytic Mitsunobu reaction in which the azo reagent is a catal yst by: Examining the substrate scope. Studying of the azo-free background reaction. Examining the use of alternative azo reagents. Examining the use of alternative phosphine reagents. Examining the use of alternative stoichiometric oxidizing reagents. To develop a catalytic Mitsunobu reaction in which the phosphine reagent is replaced by a catalyst. |
| Project Title: | Development of continuous flow processes using multifunctional supported catalysts |
| Investigator(s): | Toy PH |
| Department: | Chemistry |
| Source(s) of Funding: | Germany/Hong Kong Joint Research Scheme |
| Start Date: | 01/2008 |
| Completion Date: | 12/2009 |
| Abstract: |
| 1. To design and synthesize multifunctional supported catalysts, 2. to use the multifunctional supported catalysts in continuous flow processes for reactions such as the Trost-Lu alkynoate isomerization. |
| Project Title: | Outstanding Young Researcher Award 2007-2008 |
| Investigator(s): | Toy PH |
| Department: | Chemistry |
| Source(s) of Funding: | Outstanding Young Researcher Award |
| Start Date: | 10/2008 |
| Abstract: |
| The Awards are intended to recognize, reward, and promote exceptional research accomplishments of academic and research staff. |
| Project Title: | Multifunctional Polymeric Reagents and Catalysts for Organic Synthesis |
| Investigator(s): | Toy PH |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 10/2008 |
| Abstract: |
| 1) To prepare polystyrenes functionalized with both reagent and catalyst groups. 2) To prepare polystyre nes functionalized with multiple different catalyst ligand groups. 3) To prepare chiral multifunctional polymeric catalysts for use in asymmetric catalysis. 4) To develop efficient cross-linked heterogeneous analogues of the non-cross-linked homogeneous multifunctional polymeric reagents and catalysts. |
| Project Title: | Synthesis and catalytic applications in alkynes activation of novel polymeric materials based on ferrocenyl polyphosphines |
| Investigator(s): | Toy PH |
| Department: | Chemistry |
| Source(s) of Funding: | France/Hong Kong Joint Research Scheme - Travel Grants |
| Start Date: | 01/2009 |
| Abstract: |
| Refer to hard copy |
| Project Title: | New Chiral Phosphoric Acids Based on a Spirocyclic Framework |
| Investigator(s): | Toy PH |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 03/2009 |
| Completion Date: | 02/2010 |
| Abstract: |
| The objective of this research proposal is to examine the utility of the enantiomerically pure 1,1’-spirobiindane-7,7’-di ol framework as a scaffold for chiral phosphoric acid organocatalysts. While such organocatalysts and their conjugate bases are widely used in organic chemistry, virtually all of such acids reported in the literature are based on the chiral binol framework. Identifying new alternative diol starting materials that function effectively as chiral platforms should greatly expand the utility of such phosphoric acids and derivatives of them. |
| Project Title: | American Chemical Society National Meeting 2009 Multifunctional Polymeric Catalysts |
| Investigator(s): | Toy PH |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 08/2009 |
| Completion Date: | 08/2009 |
| Abstract: |
| N/A |
| Project Title: | Polymer-Supported, Polymeric and Phase-Tagged Chiral Phosphoric Acids for Asymmetric Catalysis |
| Investigator(s): | Toy PH |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2010 |
| Abstract: |
| 1) To prepare homogeneous and heterogeneous poly styrene-supported TADDOL-based chiral phosphoric acids and study their use in asymmetric organocatalysis applications. 2) To prepare homogeneous precipitatable poly(ethylene glycol)-supported BINOL-based chiral phosphoric acids and study their use in asymmetric organocatalysis ap plications. 3) To prepare polymeric BINOL-based chiral phosphoric acids and study their use in asymmetric organocatalysis applications. 4) To prepare fluorous chain-tagged chiral BINOL-based chiral phosphoric acids and study their use in asymmetric organocatalysis applications. 5) To prepare phosphonium ion-tagged chiral BINOL-based chiral phosphoric acids and study their use in asymmetric organocatalysis applications. |
| Project Title: | Polymer-Supported Arsines as Cataly sts for Wittig Olefination Reactions |
| Investigator(s): | Toy PH |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 03/2010 |
| Abstract: |
| The objective of this research proposal is to synthesize polymer-supported arsines based on the Rasta Resin architecture and to examine their utility as catalysts in Wittig olefination reactions of aldehydes and ketones . The Wittig reaction is one of the most powerful methods for the olefination of aldehydes and ketones, but traditional versions of it suffer from the unfortunate problem of producing an equivalent of a phosphine oxide by-product . Thus it is not very atom economical and product purification can be difficult. While several catalytic versions of this reaction that overcome this problem have been reported in the literature, they have not been widely used. This might be due to the fact that they involve the use of toxic organoarsines or tellurides as the catalyst. Thus in this project we plan to prepare heterogeneous polymer-supported organoarsines that might find more utility in such applications since they can be removed from the desired reaction product by simple filtration, and thus arsine contamination of the product can be avoided. Such a development should allow catalytic Wittig reactions using a heterogeneous polymer-supported catalyst to be more attractive than the versions previously described in the literature. |
| List of Research Outputs |
| But Y.S. , Lu J. and Toy P.H. , Organocatalytic Mitsunobu Reactions Using 3,5-Dinitrobenzoic Acid, Synlett . 2010, 21: 1115-1117. |
| Cividino P., Dheu-Andries M.-.L., Ou J. , Milet A., Py S. and Toy P.H. , Mechanistic Investigations of the Tributylphospine-Mediated Nitrone Reduction Reaction and Its Application in Cyclic Imine Synthesis, Tetrahedron Letters . 2009, 50: 7038-7042. |
| Ma C. , Kwok W.M., An H. , Guan X. , Fu Y. , Toy P.H. and Phillips D.L. , A Time-Resolved Spectroscopic Study of the Bichromophoric Phototrigger 3', 5'-Dimethoxybenzoin Diethyl Phosphate: Interaction Between the Two Chromophores Determines the Reaction Pathway, Chemistry - A European Journal . 2010, 16: 5102-5118. |
| Ma C. , Kwok W.M., An H. , Du Y. , Toy P.H. and Phillips D.L. , Femtosecond Transient Absorption and Nanosecond Time-resolved Resonance Raman Study of Photo-deprotection Reactions of Benzoin Caged Phototriggers , Femtochemistry IX: Femtochemistry, Femtobiology, and Femtophysics -- Frontries in Ultrafast Science and Technology, Beijing, China, August 8-13, 2009 . P-43: 111. |
| Ma C. , Kwok W.M. , Chan W.S. , Du Y. , Zuo P. , Kan T.W. , Toy P.H. and Phillips D.L. , Time-Resolved Spectroscopy Studies of the Photodeprotect ion Reactions of p -Hydroxyphenacyl Ester Phototrigger Compounds, Current Science . 2009, 97: 202-209. |
| Ma C. , Kwok W.M., An H. , Fu Y. , Toy P.H. and Phillips D.L. , Time-resolved Spectroscopy Studies of the Bichromophoric Phototrigger 3', 5'-dimethoxybenzoin Diethyl Phospate, The 2nd Asian Spectroscopy Conference, Seoul, Korea, November 30 - December 3, 2009 (Poster Presentation) . 2009. |
| Toy P.H. , Lectureship Award, 4th International Conference on Cutting-Edge Organic Chemistry, 2009. |
| Researcher : Tsang KY |
| List of Research Outputs |
| Ting S.W. , Cheng S. , Tsang K.Y. , van der Laak N.K. and Chan G.K.Y. , Low Activation Energy Dehydrogenation of Aqueous Formic acid on Platinum–ruthenium–bismuth Oxide at Near Ambient Temperature and Pressurew, Chemical Communications . 2009, 47: 7333-7335. |
| Researcher : Tsang YKT |
| List of Research Outputs |
| Yao H. , Ng S.M. , Tucker W.O. , Tsang Y.K.T . , Man K. , Wang X.M., Chow B.K.C. , Kung H.F., Tang G. and Lin M.C. , The gene transfection efficiency of a folate-PEI600-cyclodextrin nanopolymer, Biomaterials . 2009, 30(29): 5793-5803. |
| Researcher : Tse HS |
| List of Research Outputs |
| Tse H.S. , Hu Y.H. and Sze K.H. , Structure and Dynamics Studies of Human Ubiquitin Carbo xyl Terminall Hydrolase by NMR Spectroscopy, Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic Universit y, Hong Kong, April 24, 2010. . 2010, O-98. |
| Researcher : Tse MK |
| List of Research Outputs |
| Cho C.K.L. , Tse M.K. , Wong B.C.Y. and Sze K.H. , Structure Determination of the CTB by NMR Spectroscopy, Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic University, Hong Kong, April 24, 2010. . 2010, O-99. |
| Hui S.K. , Tse M.K. , Yang Y. and Sze K.H. , Backbone and Side-chain 1 H, 13 C and 15 N Assignments of the Ubiquitin-associated Domain of Human X-linked Inhibitor of Apoptosis Protei n , Biomol. NMR Assignments . 2010, 4: 13-15. |
| Hui S.K. , Tse M.K. , Wong B.C.Y. and Sze K.H. , Structural and Interaction Study of Ubiquitin-associated (UBA) Domain of XIAP Protein by NMR Spectroscopy, Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic University, Hong Kong, April 24, 2010. . 2010, O-96. |
| Hui S.K. , Tse M.K. , Zhou B., Wong B.C.Y. and Sze K.H. , X-linked Inhibitor of Apoptosis Protein (XIAP) Catches Ubiquitin: Determination of the Solution Structure of Ubiquitin-Associated Domain of Xiap and Mapping its Interaction Sites With Ubiquitin, The Third Asia-Pacific NMR Symposium, Jeju Island, Korea, October 25-28, 2009 . PD18, p220. |
| Tse M.K. , Structural Characterization, Domain Dissection of Human XAF1 Protein and the Application of Solvent-exposed-amide Spectroscopy in Mapping Protein-protein Interface (PhD Thesis) . 2009. |
| Researcher : Tse MK |
| List of Research Outputs |
| Cho C.K.L. , Tse M.K. , Wong B.C.Y. and Sze K.H. , Structure Determination of the CTB by NMR Spectroscopy, Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic Uni versity, Hong Kong, April 24, 2010. . 2010, O-99. |
| Hui S.K. , Tse M.K. , Yang Y. and Sze K.H. , Backbone and Side-chain 1 H, 13 C and 15 N Assignments of the Ubiquitin-associated Domain of Human X-linked Inhibitor of Apoptosis Protein , Biomol. NMR Assignments . 2010, 4: 13-15. |
| Hui S.K. , Tse M.K. , Wong B.C.Y. and Sze K.H. , Structural and Interaction Study of Ubiquitin-associated (UBA) Domain of XIAP Protein by NMR Spectroscopy, Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic Unive rsity, Hong Kong, April 24, 2010. . 2010, O-96. |
| Hui S.K. , Tse M.K. , Zhou B., Wong B.C.Y. and Sze K.H. , X-linked Inhibitor of Apoptosis Protein (XIAP) Catches Ubiquitin: Determination of the Solution Structure of Ubiquitin-Associated Domain of Xiap and Mapping its Interaction Sites With Ubiquitin, The Third Asia-Pacific NMR Symposium, Jeju Island, Korea, October 25-28, 2009 . PD18, p220. |
| Tse M.K. , Structural Characterization, Domain Dissection of Human XAF1 Protein and the Application of Solvent-expo sed-amide Spectroscopy in Mapping Protein-protein Interface (PhD Thesis) . 2009. |
| Researcher : Tsui WM |
| List of Research Outputs |
| Tsui W.M. , Huang J.S. , Tong S.M. , Kui C.F. , Che C.M. and Zhu N. , Quinoneimido Complexes of a Metalloporphyrin: Isolation, X-ray Crystal Structures, and DFT Calculations, Chemistry - A Asian Journal . 2010, 5: 759-763. |
| Researcher : Tucker WO |
| List of Research Outputs |
| Yao H. , Ng S.M. , Tucker W.O. , Tsang Y.K.T. , Man K. , Wang X.M., Chow B.K.C. , Kung H.F., Tang G. and Lin M.C. , The gene transfection efficiency of a folate-PEI600-cyclodext rin nanopolymer, Biomaterials . 2009, 30(29): 5793-5803. |
| Researcher : Vellaisamy ALR |
| List of Research Outputs |
| Han J., Chang X. .Y., Zhu L. .R., Pang M. .L., Meng J. .B., Chui S.Y. , Lai S.W. and Vellaisamy A.L.R. , Microwave-assisted Synthesis, Structure, and Tunable Liquid-Crystal Properties of 2,5-Diaryl-1,3,4-Thiadiazole Derivatives trough Peripheral n-Alkoxy Chains, Chemistry, An Asian Journal . 2009, 4: 1099-1107. |
| Xu Z. , Xiang H. , Vellaisamy A.L.R. , Chui S.Y. , Wang Y., Lai P.T. and Che C.M. , Organic field-effect transistors fabricated with N,N'-s ubstituted dialkyl-1,3,8,10-tetramethylquinacridone compounds, Applied Physics Letters . 2009, 95: 123305. |
| Researcher : Wang B |
| List of Research Outputs |
| Lai S.W. , Liu Y., Zhang D., Wang B. , Lok C.N. , Che C.M. and Selke M., Photoluminescent Properties and Singlet Oxygen Production of Cyclometalated Platinum(II) Complexes bearing Upper-ri m Phosphinated Calix[4]arenes, The Fifth International Symposium on Macrocyclic and Supramolecular Chemistry, Nara Prefecture, Japan, 6-10 June . 2010. |
| Researcher : Wang G |
| List of Research Outputs |
| Tam A.Y.Y. , Wong M.C. , Zhu N. , Wang G. and Yam V.W.W. , Luminescent Alkynylplatinum(II) Terpyridyl Metallogels Stabilized by Pt∙∙∙Pt, p - p , and Hydrophobic-Hydophobic Interactions , Langmuir . 2009, 25: 8685-8695. |
| Researcher : Wang M |
| List of Research Outputs |
| Wang M. , Zhou C. , Wong M.K. and Che C.M. , Ruthenium-catalyzed Alkylation of indoles with Tertiary Amines by Oxidation of a sp 3 C-H Bond and Lewis Acid Catalysis, Chemistry - A European Journal . 2010, 16: 5723-5735. |
| Researcher : Wang P |
| List of Research Outputs |
| Wang P. , Leung C.H. , Ma D.L. , Yan S.C. and Che C.M. , Structure-Based Design of Platinum(II) Complexes as c-myc Oncogene Down-regulators and Luminescent Probes for G-quadruplex DNA, 17th Symposium of Chemistry Postgraduate Research in Hong Kong . 2010. |
| Wang P. , Leung C.H. , Ma D.L. , Yan S.C. and Che C.M. , Structure-Based Design of Platinum(II) Complexes as c- myc Oncogene Down-Regulators and Luminescent Probes for G-Quadruplex DNA, , Chemistry - A European Journal . 2010, 16: 6900-6911. |
| Researcher : Wang X |
| List of Research Outputs |
| Du X. , Wang X. , Chan D.S.B. and Sun H. , Expression, purification and characterization of the N-terminal domain of the human copper transporter (hCt r1), 14th International Conference on Biological Inorganic Chemistry, Nagoya, Japan, July 25-30 (published in J. Biol. Inorg. Chem. 2009, 14, Suppl1, P534) . 2009, 14. |
| Wang X. , Du X. , Li H. , Chan D.S.B. and Sun H. , Effect of the N-terminal of the human high affinity copper transporter 1 (hCtr1) on cisplatin hydrolysis and uptake, 14th International Conference on Biological Inorganic Chemistry, Nagoya, Japan, July 25-30 (published in J. Biol. Inorg. Chem. 2009, 14, Suppl 1, P305) . 2009. |
| Wu Z.Y., Liu Q., Liang X., Yang X., Wang N.Y., Wang X. , Sun H. , Lu Y. and Guo ZJ , Reactivity of platinum-based antitumor drugs towards a Met- and His-rich 20mer peptide corresponding to the N-terminal domain of human copper transporter 1, Journal of Biological Inorganic Chemistry . 2009, 14: doi: 10.1007/s00775-009-0576-7. |
| Researcher : Wang Y |
| List of Research Outputs |
| Lui E.L.H. , Shum K.T. , Sam L. , Wang Y. , Watt R.M. and Tanner J.A. , Aptamers Against Polyphosphate Kinase 2 (PPK2) From Mycobacterium Tuberculosis As A Potential Approach Of Novel Anti-Tuberculosis Therapy , CUHK Croucher Advanced Study Institute “Structure-Based Screening and Design of Ligands for Protein Targets” . 2009. |
| Shum K.T. , Lui E.L.H. , Wang Y. , Watt R.M. and Tanner J.A. , Aptamer-mediated inhibition of Mycobacterium tuberculosis polyphosphate kinase 2. , 2010 Hong Kong Inter-University Biochemistry Postgraduate Symposium . 2010. |
| Researcher : Watt RM |
| Project Title: | Polyphosphate metabolic enzymes as potential targets for anti-tuberculosis and general antibiotic drug development |
| Investigator(s): | Watt RM, Huang J, Tanner JA |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 07/2007 |
| Abstract: |
| Biochemical and biophysical characterization of enzyme activities The four M. tuberculosis genes will be cloned, expressed and purified, and their catalytic activities will be characterized in detail, by screening a large selection of potential substrates for turnover. Biochemical assays will be developed, and the catalytic kinetic parameters will be thoroughly investigated. Special attention will be paid to reversibility, reaction rates, as well as substrate and product binding affin ities. Where applicable, assays will be miniaturized and adapted for future high throughput inhibitor screening. Binding and Inhibition studies – synthesis of non-hydrolysable substrate analogues As the selected enzymes putatively share a binding affinity for poly-phosphate, we will synthesize non-hydrolyzable imido-polyphosphate (imido poly-P) molecules, with a variety of chain lengths, for binding and inhibition studies (see appendix 1). Substrate-based affinity chromatography - isolate related enzymes from other bacteria The imido poly-P will be chemically linked to a chromatography resin, to create a novel protein affinity matrix. This will be used in ‘pull-down’ experiments, to identify function ally related proteins within cell extracts prepared from a representative set of (non-pathogenic) bacterial species. |
| Project Title: | New DNA recombination systems for microbial genome engineering and proteome analysis |
| Investigator(s): | Watt RM |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 12/2007 |
| Completion Date: | 11/2009 |
| Abstract: |
| Scope of the Problem Bacteria are the most diverse, most abundant, and most adaptable life forms on our planet. Although we have isolated, cultured and chara cterized many thousands of these microorganisms – environmental metagenomic sequencing projects have indicated that what we have characterized so far constitutes only a small fraction of what actually exists. As efforts to sequence and annotate the genomes of these new bacterial species have greatly accelerated, the development of general and robust methods that may be used to modify and manipulate the genomes of these organisms has not been so rapid. This is a significant problem, as the lack of convenient methods for genome modification greatly hinders efforts to analyze the functions of encoded genes, especially in comprehensive functional genomic investigations. Although methods exist for efficient and specific chromosome modification within several eubacterial species (most notably for the model organism Escherichia coli) there are no convenient methods for ‘DNA engineering’ within the vast majority of bacteria – many of which are key human pathogens, or are microbes with important industrial uses. Such studies are crucial in several respects: e.g. for the identification of genes of essential function in pathogenic bacteria, which may be targets for future antibiotic therapies; or for the characterization of genes of unknown or suggested function, which may be involved in the microbial production of pharmaceuticals, neutrice uticals or biofuels. I will directly address this issue with the research described within this proposal. For this investigation, I will focus on two relatively disparate species: Laribacter hongkongensis and Vibrio cholerae, which are members of the beta- and gammaproteobacteri a classes, respectively. Laribacter hongkongensis was recently identified by researchers in the Microbiology Department at HKU as being 'associated with traveler’s diarrhea’. Being a member of the Neisseriaceae family, it is closely related to both the Chromobacterium and Neisseria genera. Notable members of these genera include C. violaceum, which synthesizes the important anti-tumorigenic natural product violacein; and N. meningitidis and N. gonorrhoeae, which cause bacterial meningitis and gonorrhea, respectively. Vibrio cholerae is the etiological agent of cholera, which is responsible for hundreds of thousands of deaths each year (the majority of which are children in the developing world). As well as being important human pathogens, vibrio species are found in many different marine environments, and are one of the most (if not the most?) abundant bacterial genera on Earth. Other notable members include V. parahaemolyticus and V. vulnificus, which also commonly cause gastro-intestinal diseases. Both these organisms present quite different challenges, which are broadly representative of the problems commonly encountered when attempting to perform general molecular biology techniques within other ba cterial species. Therefore, they are excellent representative model organisms to work with, for the development of general bacterial DNA engineering procedures. L. hongkongensis was only recently discovered, and thus far, no methods for targeted gene alteration have been reported. It appears to have a reasonably high transformation efficiency, but does not support the replication of any of the commonly used bacterial plasmids. Consequently, only species-specific ‘shuttle vectors’ (constructed from endogenous cryptic plasmids) may be used for episomal gene expression within this organism. Conversely, V. cholerae has been intensively studied for decades. However, largely due to its poor transformation effi ciency, versatile techniques for genetic manipulation have yet to be developed. Thus far, targeted gene manipulations in V. cholerae have been achieved by relatively complex and time-consuming procedures, generally involving the introduction of ‘suicide’ vectors by transduction, conjugation or transformation; which all occur with low efficiencies. Key Objectives For this proposal, I will develop molecular biology ‘tools’ and techniques that can be used to efficiently modify the genomes of both Laribacter hongkongensis and Vibrio cholerae. The materials and procedures developed should be applicable for the modification of the genomes of related bacterial species – many of which are major human pathogens. (These further investigations will be pursued in future projects, funded by outside grants to be sought during 2008 and 2009). Specifically, I will investigate the feasibility of using phage- and prophage-derived proteins that promote efficient homologous recombination between double stranded DNA ‘targeting molecules’ and the chr omosome. The best studied of these systems is the ‘Red’ set of proteins from bacteriophage lambda, which comprises Bet and Exo. The Exo protein is a 5’ to 3’ single stranded exonuclease, which degrades the ends of the double stranded DNA ‘targeting molecules’ forming long 5’-single stranded regions. Bet binds to these regions of ssDNA and promotes their annealing with homologous regions on the chromosome (or plasmid). The DNA intermediates formed are ‘resolved’, ‘trimmed’ and nicks are ligated by endogenous host proteins, resulting in the formation of the desired genetic alteration. The Red recombination system has been successfully utilized in E. coli to modify both episomal (e.g. plasmid) and chromosomal DNA with efficiencies that may be as high as 20%. Normal efficiencies are in the range 0.01 to 1%, which necessitates the use of selectable markers such as genes conferring resistance to antibiotics. Using bioinformatic methods, I have identified two different sets of Bet and Exo proteins for use in this investigation, and have initiated a preliminary investigation into their activities. One set is located a putative prophage on the L. hongkongensis genome, identified from (unpublished draft) sequencin g data given to me by Prof. Patrick Woo (Microbiology, HKU). The second set are housed on the SXT ‘conjugative genetic element’ that infects V. cholerae, which was supplied by Prof. Matthew Waldor (Harvard Medical School). For this investigation I will: • Characterize the activities of the four identified Bet and Exo recombination proteins in vitro using a variety of biophysical techniques • Determine the biological activities of these two pairs of proteins in vivo (using a genetic reporter system within E. coli) • Introduce these pairs of proteins into L. hongkongensis and V. cholerae either on plasmi ds (i.e. episomally) or insert them onto the chromosome • Develop protocols for the specific modification of the V. cholerae and L. hongkongensis genomes with DNA ‘targeting molecules’, through homologous recombination-based processes catalyzed by these proteins • Use the DNA engineering techniques and tools generated to formula te methods enabling the detailed analysis of the proteomes of these two bacterial species |
| Project Title: | A Molecular toolbox for genetic, proteomic and metabolic engineering in the ethanol-prod ucing bacterium Zymomonas mobilis |
| Investigator(s): | Watt RM, Huang J |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2009 |
| Abstract: |
| 1) Construct stable and versatile new Z. mobilis – E. coli shuttle vectors for the inducible expression of foreign genes in Z. mobilis; 2) Characterize the activities of two new pairs of Bet/Exo family DNA recombination proteins, using well-established reporter systems in E. coli; 3) Determine the optimal parameters for engi neering the Z. mobilis chromosome using shuttle vector-based Bet/Exo DNA recombination proteins; 4) Develop a tandem-affinity purification (TAP) protein labeling technique, which can be used to identify proteins interactions within Z. moblis; 5) Determine the feasibility of engineering Z. mobilis for the production of monterpene and sesquiterpene natural products |
| Project Title: | Oral Treponemes: Proteomic and genetic analysis |
| Investigator(s): | Watt RM, Leung WK |
| Department: | Dental Faculty |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 05/2009 |
| Abstract: |
| Periodontal diseases are chronic polymicrobial infections of the tissues and bone surrounding and supporting the tooth. After tooth decay, these are the second most common diseases in the global population, with a prevalence of ca. 30-50% in developed countri es (Loesche 2001). Diseases of the human tooth supporting structures range from the relatively mild gingivitis (gum inflammation and bleeding), to highly severe forms including acute, chronic or necrotizing periodontitis. Several hundreds of different bacterial species commonly inhabit the oral cavity. Many of these cooperate to form a tough and structurally-complex biofilm on the tooth surface, commonly referred to as plaque. The plaque biofilm is composed of an inter-dependent, spatially-organized community of bacteria within an extra-cellular polymer ic matrix. Plaque may further mineralize to form calculus (tartar), which is extremely resistant to physical removal (e.g. by brushing or flossing). The formation and calcification of plaque is exacerbated by poor oral hygiene and healthcare, enabling it to encroach below the gum line, into the shallow gap between the tooth and the gum (the sulcus). If untreated, this gradually leads to the formation of a deep pocket between the tooth and gingiva (gum), which is low in oxygen. This greatly alters the dynamic composition of the bacterial flora present within the sub-gingival plaque ; with certain anaerobic species being significantly enriched (see below). Bacterial (endo-)toxins and other secreted or surface virulence factors cause severe localized inflammation of the gingiva (gums). A number of bacterial species are known to adhere to and invade the epithelial cells within the periodontal pocket and proteolytically degrade structural and connective tissues such as collagen and fibronectin. These activities, in combination with the host inflammatory response cause localized necrosis (cell death and tissue damage). Bacterial virulence factors also inhibit the activities of gingival fibroblast (matrix-forming) and cementoblast (cementum-forming) cells. This inhibits bone and cementum regeneration, further weakening the attachment of th e tooth. Ultimately, there is severe ‘pocket’ formation, gum recession and eventually tooth loss. There are a small number of anaerobic bacterial species that are strongly associated with periodontal diseases, including: Porphyromonas gingivalis; Fusobacterium nucleatum; Tannerella forsythia; Aggregatibacter actinomycetemcomit ans and Treponema denticola (Haffajee 2005, Socranski 2005). Being highly motile, with an unusual spiral-shaped cell morphology, the Gram negative spirochete T. denticola is the most poorly studied of these periodontal pathogens; and is arguably the most biologically interesting. There are ca. 60 treponemal species (or phylotypes) known to inhabit the human mouth, many of which are suspected of playing important roles in periodontal diseases. However, due to the paucity of detailed molecular analyses, only T. denticola (and to a less well-proven extent, T. socranskii) have thus far been demonstrated to be strongly associated with these diseases (Sela 2001, Holt 2005). Due to their fastidious nature, only four oral treponemes can be reliably cultured ex vivo (T. denticola, T. pectinovorum, T. socranskii and T. vincentii) and have been studied in any detail (Chan 2000). As a result, very little is known about their biochemistry, their cellular and molecular biology, or their role in periodontal diseases. Furthermore, very little is known about the global distribution of oral treponeme species, and how this may be related to the frequency or severity of periodontal diseases. T. denticola (ATCC 35405) is the only oral treponeme species whose genome has been sequenced (Seshadri 2004). It has a compact circular genome (2,843,201 nt; 91% coding; 37% G/C) with 2767 protein encoding genes. Its closest homologue is Treponema pallidum (the causative agent of venereal syphilis); although the genome of this obligate human parasite is significantly reduced in size (1.1 Mb), having diverged considerably from a common ancestor. Even though several surface proteins have been identified as potential virulence factors (e.g. major surface protein, Msp) (Ellen 2005, Sela 2001, Holt 2005), thus far, there have been no detailed or systematic analyses performed on the proteome of T. denticola. Consequently, the detailed composition of its surface-exposed or secreted proteins is unknown. This is highly significant, as some of these (as yet unidentified) periplasmic, membrane-integrated or exported proteins are likely to be directly involved in the pathogenesis of this group of bacteria. These protein s may promote co-aggregation or association with other (pathogenic) bacteria, or may directly mediate interactions with fibroblasts, osteoblasts, cementoblasts or the host epithelia cells, to potentiate the periodontal infection. In this proposal, we have two major aims: 1) to characterize the proteins expressed by T. denticola, and 2) identify which treponeme species (phylotypes) are present in heavily- infected periodontal pockets of (Hong Kong Chinese) patients with severe periodontitis. The results of our studies will generate a comprehensive body of data that will significantly expand our current understanding of the pathogenesis of oral treponemes. Our specific objectives are as follows: 1) Characterization of the proteome of Treponema denticola We will characterize a) the ‘total’ proteome of T. denticola grown in liquid and semi-solid culture, i.e. identify the proteins that are expressed to detectable levels within the cell. We will further identify the proteins that are associated with the membrane, as well as those that are exported into the periplasm or secreted from the cell. We wil l also generate the first set of annotated proteome ‘reference maps’ for this organism. 2) Genetic analyses of oral treponemes in patients with periodontal diseases We will identify the treponemal species (genetic phylotypes) present within sub-gingival plaque taken from patients with severe periodontitis, using 16S ribosomal RNA gene sequence analysis. Samples from both diseased and ‘healthy’ periodontal pockets will be analyzed and compared. We will establish the phylogenetic diversity of species present within these sites, and will compare and contrast our findings with data obtained from related molecular analyses of periodontal pathogens (Aas 2005 , Choi 1994, Dewhirst 2000, Kumar 2005, Paster 2001). |
| Project Title: | Genes get 'recT' : new and improved methods for bacterial DNA engineering |
| Investigator(s): | Watt RM, Huang J, Tanner JA |
| Department: | Dental Faculty |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 01/2010 |
| Abstract: |
| 1) Optimize conditions for LHK-Bet-mediated ssDNA recombination in E. coli; 2) Investigate relative dsDNA recombination activities of three newly-identified sets of recombinase/exonuclease proteins in E. coli; 3) Develop recombineering technologies within L. hongkongensi s and N. lactamica; 4) Establish which conserved structural elements and regions within the Bet/RecT family are involved in: a) DNA recombination activity; b) DNA binding and strand exchange activities; c) determining recombinase/exonuclease binding specificity; d) modulating oligomerization and nucleofilament formation. |
| Project Title: | Society for General Microbiology Spring 2010 Meeting Versatile enzymatic system for the production of guanosine polyphosphates |
| Investigator(s): | Watt RM |
| Department: | Dental Faculty |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 03/2010 |
| Completion Date: | 04/2010 |
| Abstract: |
| N/A |
| Project Title: | A molecular typing system for Treponema denticola: an enigmatic oral pathogen |
| Investigator(s): | Watt RM, Leung WK |
| Department: | Dental Faculty |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 04/2010 |
| Abstract: |
| Background The term ‘periodontal disease’ refers to a spectrum of chronic infectious inflammatory diseases of the tissues and bone that surround and support the teeth (Loesche, 2001). These range from the relatively mild gingivitis (gum inflammation and bleeding), to highly severe forms including acute, chronic or necrotizing periodontitis. Periodontal diseases may be considered to be mixed-species, bacterial biofilm diseases (Schaudi nn, 2009). They share a common etiology; beginning with the gradual encroachment of tooth-associated biofilms below the gumline (subgingival plaque), leading to an overpopulation of anaerobic, proteolytic bacteria. These ‘periodontal disease-associated pathogens’ progressively degrade the gingival epithelium, creating a deep and persistent ‘pocket’ of infection around the tooth. Bacterial products such as lipolysaccharides (LPS), toxins and proteases directly cause host cell and tissue damage. They also elicit the release of cytokines and other inflammatory mediators that promote the resorption of alveolar bone and the destruction of the tooth-attachment and supporting tissues, ultimately leading to tooth loss. The etiology of periodontal disease is extremely complex as it involves a combination of host, environmental and microbiological factors. Elevated populations of the oral spirochete bacterium Treponema denticola are strongly associated with the most severe forms of periodontal disease (Sela, 2001). More than 60 species (or phylotypes) of spirochetes have been identified in the oral cavity; all of which belong to the genus Treponema (Dewhirst, 2000). Due to their fastidious nature, less than a quarter of these are cultivatable. This has severely hampered efforts to study and compare their genetic composition, physiology and biology; and to identify common or unique pathogenic attributes. T. denticola is the most highly-studied oral spirochete, and is used as a model organism for several uncultivatable (non-oral) pathogenic species such as Treponema pallidum, the causative agent of venereal syphilis. T. denticola was the first and only oral spirochete to have its genome sequenced (Seshadri, 2004). With such limited genetic information available, no systematic comparative genetic investigations or genetic typing systems have been developed for any treponeme species. After complete genome sequencing, which is expensive and impractical for routine use, multi locus sequence typing (MLST) is the best way to unambiguously identify or characterize a particular microbial isolate (Urwin, 2003). This molecular typing technique is invaluable for the rapid identification of pathogenic strains for epidemiological purposes. Notable pathogens for which MLST systems have developed include: Candida albicans, Neisseria meningitidis and Staphylococcus aureus. It is also a powerful tool for studying evolutionary and population biology. The basic principle of MLST involves using consensus primer sets to PCR-amplify and sequence 300-600bp sections from 7-10 ‘reference’ or ‘housekeeping’ genes within the isolate of interest. Genetic variations or ‘alleles’ within each of these reference genes are then compared against a large reference dataset (e.g. at the online repository at www.mlst.net). To construct an MLST reference database, the sequences for these 7-10 reference genes must first be determined within a large set of isolates of diverse origin. A World-class Microbiological Resource The world’s pre-eminent expert on the biology and culture of oral treponeme bacteria: Dr. Chris Wyss of the University of Zurich retired this summer. He has generously gifted the PI and CoI his entire collection of treponeme strains, which he has isolated and accrued over the past 25 years. In essence, he has given us the world’s most comprehensive collection of oral treponeme species; comprising >120 diverse isolates and reference strains belonging to over 15 species, obtained from animal as well as human sources. Some of the more poorly-characteri zed ones have unusual cell morphologies, atypical phenotypic or biochemical profiles, and may even constitute novel species. Over the past few months we have begun culturing representative stocks, to check the viability of the collection. We have confirmed that the stocks are viab le, and the collection is accurately labeled. Scope of the Problem The diversity, phylogeny and ancestry of T. denticola have never been directly investigated. This is an important issue, as researchers who are investigating the biology and pathology of T. denticola have used a variety of different ATCC reference strains or well-studied clinical isolates. Although these strain s have distinct cell morphologies, phenotypic properties and serotypes, nobody has ever systematically investigated how similar or different these strains are at the genetic level. T. denticola plays a key role in destructive periodontal diseases, but we have no idea which strains are the most common or virulent within the oral cavity. We presently do not have the genetic knowledge or diagnostic tools to answer this question. Here, we will directly address these key issues. Our working hypothesis is that there is a subset of T. denticola strains that have increased virulence within infected periodontal pockets, which cause a high level of tissue damage and inflammation. The MLST system and genetic information developed through this project will enable us, and other teams of oral microbiologists, to test this and numerous other working hypotheses. Objectives in point form 1) Determine the sequences of eight ‘reference’ genes within 16 diverse strains of T. denticola. 2) Develop a multi locus sequence typing (MLST) system for T. denticola. The sequence dataset from objective (1) will be used to guide the design of the consensus primers used for this MLST system. 36 diverse strains of T. denticola isolated from humans, cats and dogs will be used to form the reference set. 3) Analyze the phylogeny of each gene within all the strains studied using a variety of computational methods. This will enable us to gauge overall genetic diversity within this species, and establish the ancestry and ‘relatedness’ of the most highly used laboratory strains. |
| Researcher : Wei G |
| List of Research Outputs |
| Wei G. and Chiu P. , Studies Toward the Synthesis of the Pseudolaric Acids Based on RCM Reactions, The 17th Symposium on Chemistry Postgraduate Research in Hong Kong . The Hong Kong Polytechnic University, The Hong Kong Polytechnic University, 2010, O-94. |
| Researcher : Wong ELM |
| List of Research Outputs |
| Sun R.W.Y. , Ng F.Y. , Wong E.L.M. , Zhang J. , Chui S.Y. , Shek L. , Lau T.C. and Che C.M. , Dual anti-angiogenic and cytotoxic properties of ruthen ium(III) complexes containing pyrazolato and/or pyrazole ligands , Dalton Transactions . 2009, 10712-10716. |
| Researcher : Wong HL |
| List of Research Outputs |
| Mak S.K. , Wong H.L. , Leung Q.Y. , Tam W.Y. , Chan W.K. and Djurisic A. , The use of sublimable chlorotricarbonyl bis(phenylimino)acenaphthene rhenium(I) complexes as photosensitizers in bulk-heterojunction photovoltaic devices, Journal of Organometallic Chemistry . ELSEVIER SCIENCE SA, 2009, 694: 2770-2776. |
| Wong H.L. , Ko C.C. , Lam S.W.H. and Yam V.W.W. , Design And Synthesis Of New Classes Of Photochromic Diarylethene-containing Heteroacenes And Their Switchable Luminescence Properties, The 13 th International Symposium on Novel Aromatic Compounds (ISNA-13), Luxembourg City, July 19 – 24, 2009 . 2009, SA028. |
| Wong H.L. , Ko C.C. , Lam S.W.H. , Zhu N. and Yam V.W.W. , Design and Synthesis of a New Class of Photochromic Diarylethene-Containing Dithieno[3,2-b:2’,3’-d]pyrroles and Their Switchable Luminescence Properties, Chemistry - A European Journal . 2009, 15: 10005-10009. |
| Researcher : Wong HL |
| List of Research Outputs |
| Mak S.K. , Wong H.L. , Leung Q.Y. , Tam W.Y. , Chan W.K. and Djurisic A. , The use of sublimable chlorotricarbonyl bis(phenylimino)acenaphthene rhenium(I) complexes as photosensitizers in bulk-heterojunc tion photovoltaic devices, Journal of Organometallic Chemistry . ELSEVIER SCIENCE SA, 2009, 694: 2770-2776. |
| Wong H.L. , Ko C.C. , Lam S.W.H. and Yam V.W.W. , Design And Synthesis Of New Classes Of Photochromic Diarylethene-containing Heteroacenes And Their Switchable Luminescence Properties, The 13 th International Symposium on Novel Aromatic Compounds (ISNA-13), Luxembourg City, July 19 – 24, 2009 . 2009, SA028. |
| Wong H.L. , Ko C.C. , Lam S.W.H. , Zhu N. and Yam V.W.W. , Design and Synthesis of a New Class of Photochromic Diarylethene-Containing Dithieno[3,2-b:2’,3’-d]pyrroles and Their Switchable Luminescence Properties, Chemistry - A European Journal . 2009, 15: 10005-10009. |
| Researcher : Wong JKY |
| Project Title: | Luminescent benzylic amide macrocycle-based metal complexes with potential sensing capabilities |
| Investigator(s): | Wong JKY, Yam VWW |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 11/2004 |
| Abstract: |
| To synthesise macrocycle-containing metal complexes; to add guest and test the benzylic amide macrocycle-based metal complexes as luminescent sensors. |
| Researcher : Wong KC |
| List of Research Outputs |
| Wong K.C. , Lanthanide Complexes Containing Macrocyclic Ligands for Magnetic Resonance Imaging Contrast Agents (PhD Thesis) . 2010. |
| Researcher : Wong KL |
| List of Research Outputs |
| Law G.L. , Wong K.L. , Man C.W.Y. , Tsao G.S.W. and Wong W.T., A two-photon europium complex as specific endoplasmic reticulum probe., Journal of Biophotonics . 2009, 2(12): 718-724. |
| Researcher : Wong MC |
| Project Title: | Design and Synthesis of Molecular Chemosensors and Logic Gates Based on Förster Resonance Energy Transfer (FRET) of Transition Metal Complex Chromophores |
| Investigator(s): | Wong MC |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 08/2007 |
| Abstract: |
| To design, synthesize and characterize various organic chromophore-containing ligands, in which the ligating sites and the chromophore are linked by vario us bridging spacers, and to study their fundamental photophysical properties in order to obtain basic spectroscopic information for comparison purpose. To design, synthesize and characterize a series of luminescent transition metal complexes-based FRET systems through the coordination of the newly synthesized organic chromophore-containing ligands to the selected d-block metal centres of iridium(III) and rhenium(I). To study the electronic absorption and luminescence behaviours of the newly synthesized FRET systems to elucidate the effects of the nature of the metal centres, organic chromophoric donor/acceptor units as well as bridging spacers on their FRET properties. To correlate the FRET efficiency with the structure of the bridging spacer and to explore the utilization of the FRET response as sensory probes resulting from structural changes that occur upon external stimulations. To extend the works to three-component FRET systems consisting of three donor/acceptor chromophores and to investigate the potential of their two-step FRET processes for use as molecular logic gates. Impact: In this project, novel classes of FRET systems derived from the use of luminescent d-block transition metal complexes as the donor or acceptor chromophore will be designed and synthesized. The electronic absorption and luminescence properties as well as the FRET behaviours of these newly synthesized luminescent transition metal complex-based FRET systems will be studied in order to correlate the FRET efficiencies with the nature of the metal centres, organic chromophoric donor/acceptor as well as bridging spacers. By making use of various functionalized bridging spacer and versatile synthet ic methodologies, such FRET systems may function as chemosensors and molecular logic gates. Through a judicious design and choice of ligand systems with different functionalized bridging spacers, the efficiency of FRET is anticipa ted to be varied upon introduction of external stimuli, such as cleavage of spacers or addition of guest. Extension of the work to the multi-component FRET assemblies with at least one transition metal complex moiety as the donor/acceptor unit will also be made for the investigati on of multi-step FRET processes. By virtue of the superiorities of relatively high stability and colour-tuning capability spanned over the visible spectrum, the present project aims to explore the use of luminescent d-block transi tion metal complexes for FRET studies in systems coupled with organic fluorophores. This concept would aid the future design and development of FRET application by providing another option for the search of chromophoric replacement. |
| Project Title: | Luminescent Heterometallic Lanthanide(III) Complexes of d-f Systems |
| Investigator(s): | Wong MC |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 04/2009 |
| Completion Date: | 03/2010 |
| Abstract: |
| There has been continuous interest in the development of the coordination of trivalent lanthanide ions due to the wide variety of potential applications, with the particular interest as luminescent chemosensors for medical diagnosis, contrast agents for magnetic resonance imaging, and optical imaging for cell labeling. Luminescence from lanthanide(III) complexes has been of interest for many years. The emission is assigned to transitions between states of a given fn configuration, which are strictly parity forbidden resulting in emission lifetimes in the millisecond regime. Transitions from one J state of an fn configuration to another J state of this configuration are extremely sharp, resulting in the line-like luminescence and these transitions are easily recognizable, making lanthanide(III) ions ideal candidates for optical probes. In addition, their emission colors cover the entire spectrum from UV to visible and near-infrared (NIR) ranges (0.3-2.2 μm). The intense, long-lived, and line-like emission of lanthanides(III), such as Eu(III) and Tb(III) in the visible region, has made them of interest for a range of applications, from biological assays to display devices, and as such, their photophysical properties have received a huge amount of attention. In light of the above advantages, interest has developed for the design of efficient luminescent lanthanide(III) coordination compounds in recent years. However, the forbidden nature of f-f transitions is apparent due to the small molar extinction coefficients observed for lanthanide(III) ions (ε < 10 dm3 mol−1 cm−1). Traditionally, sensitization of lanthanide(III) luminescence is achieved by π-conjugated organic aromatic chromophores that are directly coordinat ed to the lanthanide(III) centers and strongly absorb UV light. The search for new chromophores to act as sensitizers of visible and near-infrared luminescence from lanthanides continues. In view of the fact that luminescent d-block transition metal complexes possess the advantages of high chemical and photo- stabilities as well as ready color-tuning, such kind of complexes might also be used as the chromophoric sensitizer for the luminescence of lanthanide(III) compound in d-f hybrid systems. The present project aims to design and synthesize different types of d-f hybrid systems and to study their photophysical properties. The synthetic methodologies are mainly based on two approaches. One involves the preparation of different bridging ligands with various ligating sites and to coordinate them to transition metal centers and lanthanide ions in stepwise manner. According to the recently extensively studied “click” reaction, another technique is proposed in which the transition metal and lanthanide complex es separately bearing the azide and alkynyl functional groups could be brought together via the formation of five-membered triazole ring. Similar to the extensive studies performed on the correlation of the lowest ligand triplet state energy with the photophysical properties, for examples of the luminescence quantum yield and life-time of lanthanide(III) compounds, such transition metal subunits with high luminescence colour-tunin g ability are anticipated to sensitize the metal-centered (MC) luminescence of different kinds of lanthanide(III) with various MC energy levels. |
| Project Title: | 42nd International Union of Pure and Applied Chemistry (IUPAC) Congress A Luminescent Trinuclear Platinum(II) Pt3C2 System Having a “Naked” CC2- Ligand Swapping Amongst Three Unsupported Platinum(II) Moieties |
| Investigator(s): | Wong MC |
| Department: | Chemistry |
| Source(s) of Funding: | URC/CRCG - Conference Grants for Teaching Staff |
| Start Date: | 08/2009 |
| Completion Date: | 08/2009 |
| Abstract: |
| N/A |
| Project Title: | Monodisperse Luminescent Alkynylplatinum(II) Terpyridyl Oligomers: Design, Synthesis and Photophysical Properties |
| Investigator(s): | Wong MC |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 03/2010 |
| Abstract: |
| There has been an increasing interest on the organic π-conjugated polymers as advanced materials for electron ic and photonic applications in the past decades. In view of the inherent synthetic flexibility, potential ease of processing, and the possibility of tailoring characteristic properties to accomplish a desired function, it is anticipated that such organic polymers are promising candidates for manifold applications in materials sci ence. Due to the low solubility, the direct analytical characterization and physical study of extended π-chain polymers with high molecular weight is often hampered. Moreover, Structural defects also represent a common obstacle towards obtaining sound physical data. Soluble, monod isperse oligomers with the same number of monomer units are considered as finite model systems in order to offer the possibility to attain the electronic, photonic, thermal, and morphological properties of their corresponding polydisperse high molecular weight analogues. Furthermo re, the monodisperse π-conjugated oligomers of defined length and constitution arises from their potential can act as molecular wires in molecular scale electronics and nanotechnological devices. A variety of spectacular molecular architecture has resulted from the efforts aimed at the construction of such wires. There has been a surge of interest concerning the synthesis and properties of π-conjugated polymers that contain transi tion metal complexes. Much of the work in this area has focused on new materials for application such as light-emitting diodes, photorefractivity, photoconductivity, electrochromi sm, and chemical sensing. There are only a few reported examples of conjugated polymers where metal centers are in conjugation with the polymer’s π-system with direct electronic communication. Although there are some reports on the photophysical properties of platinum(II) alkynyl complexes and polymers, such studies are mainly confined to the platinum(II) alkynyl systems of P-don or ligand with two alkynyl and two phosphino ligands in trans- configuration. The first series of platinum(II) terpyridyl alkynyl complexes, [Pt(N^N^N)(C≡CR)]X, through the incorporation of alkynyl moieties into the platinum(I I) terpyridyl MLCT chromophore have been reported. These complexes were found to exhibit interesting photophysical behaviours and the luminescence properties of platinum(II) terpyridyl system were found to be improved by the incorporation of the strong σ-donating alkynyl ligand to the fourth position of platinum(II) terpyridyl moi ety. In this project, a new series of monodisperse luminescent alkynylplatinum(II) terpyridyl oligomers will be designed and synthesized. In light of the interaction of alkynyl ligand with metal centres via pπ–dπ overlap with dire ct electronic communication, the spectroscopic and photoluminescence properties of the platinum(II) terpyridyl alkynyl system will be studied and correlated with the nature and number of monomer unit. The present project should provide an exploration and exploitation of this new class of monodisperse alkynylplatinum(II) terpyridyl oligomers as well as the understanding of their luminescence properties and origins. Through a judicious design and variation of monomer unit as well as the introduction of donor and acceptor moieties within the oligomer, energy transfer and non-linear optical behaviours, and charge separation process will also been studied. |
| List of Research Outputs |
| Au K.M. , Wong M.C. , Chen Z. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , A Novel Class of Bis-cyclometalated Alkynylgold(III) Complexes – Synthesis, Characterization, Photophysic s, Electrochemistry and the First Observation of Electrogenerated Chemiluminescence, The 5th International Conference on Gold Science, Technology and its Applications (organized by World Gold Council), Heidelberg, Germany, July 26–29, 2009 . |
| Au K.M. , Wong M.C. , Zhu N. and Yam V.W.W. , Luminescent Cyclometalated N-Heterocyclic Carbene-Containing Organogold(III) Complexes: Synthesis, Characterization , Electrochemistry, and Photophysical Studies, Journal of the American Chemical Society . 2009, 131: 9076-9085. |
| Au K.M. , Chen Z. , Wong M.C. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , Synthesis, Characterization, Photophysical Studies, Electrochemistry and Electrogenerated Chemiluminescence of Bis-cyclometalated Alkynylgold(III) Complexes and their Applications in Organic Light-Emitting Devices , The 42 nd International Union of Pure and Applied Chemistry (IUPAC) Congress, Glasgow, United Kingdom, August 2-7, 2009 . P701_030. |
| Au K.M. , Chen Z. , Wong M.C. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , Synthesis, Characterization, Photophysical Studies, Electrochemistry and the First Observation of Electro generated Chemiluminescence of Bis-cyclometalated Alkynylgold(III) Complexes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P217. |
| Chan H.Y. , Lam J.W.Y., Wong M.C. , Tang B.Z. and Yam V.W.W. , Chiral Poly(4-ethynylbenzoyl-L-valine) Induced Helical Self-assembly of Platinum(II) Terpyridyl Complexes with Tunable UV-vis Absorption, Emission and Circular Dichroism Changes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P214. |
| Li Y.G., Wong M.C. , Tam A.Y.Y. , Wu L.X. and Yam V.W.W. , Thermo- and acid-responsive photochromic spironaphthoxazine-contain ing organogelators, Chemistry - A European Journal . 2010, 8690-8698. |
| Song H.O., Chan T.W. , Li M. , Wong M.C. , Yam V.W.W. and Wu L.X., Synthesis, Characterization and Fluorescence Resonance Energy Transfer (FRET) Studies of Rhenium(I) Complexes With Coumarin Pendants, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P210. |
| Tam A.Y.Y. , Wong M.C. and Yam V.W.W. , Influence of Counter-Anion on the Chiral Supramolecular Assembly of Alkynylplatinum(II) Terpyridyl Metallogels that are Stabilized by Pt···Pt and p - p Stacking Interactions, 5th International Symposium on Macrocyclic and Supramolecular Chemistry . 2010. |
| Tam A.Y.Y. , Wong M.C. , Zhu N. , Wang G. and Yam V.W.W. , Luminescent Alkynylplatinum(II) Terpyridyl Metallogels Stabilized by Pt∙∙∙Pt, p - p , and Hydrophobic-Hydophobic Interactions , Langmuir . 2009, 25: 8685-8695. |
| Tam Y.Y. , Wong M.C. , Zhu N. and Yam V.W.W. , Luminescent Metallogel of Alkynylplatinum(II) Terpyridyl Complexes: Interplay of Metal ... Metal, p - p and Hydrophobic-Hydrophobic Interactions on Gel Formation, , The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P216. |
| Wong M.C. , Lam S.W.H. , Zhou Z.Y. and Yam V.W.W. , A Luminescent Trinuclear Platinum(II) Pt 3 C 2 System Having a “Naked” C º C 2- Ligand Swapping Amongst Three Unsupported Platin um(II) Moieties, The 42 nd International Union of Pure and Applied Chemistry (IUPAC) Congress, Glasgow, UK, August 2-7, 2009 . P701_43. |
| Wong M.C. , Asian and Oceanian Photochemistry Association Prize for Young Scientists (the APA Prize for Young Scientists, 2009-2010), Asian and Oceanian Photochemistry Association (the APA) . 2010. |
| Wong M.C. , Lam S.W.H. , Zhu N. , Zhou Z.Y. and Yam V.W.W. , Luminescent Polynuclear Alkynylplatinum(II) Complexes with p -Coordination of Various Metal Ions, , The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 (Oral presentation by Dr Keith Man-Chung Wong) . 2009. |
| Yam V.W.W. , Song H. , Chan T.W. , Zhu N. , Tao C.H. , Wong M.C. and Wu L.X., Synthesis, Characterization, Ion-Binding Properties, and Fluorescence Resonance Energy Transfer Behavior of Rhenium(I) Complexes Containing a Coumarin-Appended 2,2′-Bipyridine, Journal of Physical Chemistry C . 2009, 113: 11674-11682. |
| Yin Z.D., Tao C.H. , Wong M.C. , Yam V.W.W. and Wu L.X., A Novel Bodipy-based Probe and its Magnesium Ion-responsive Spectra, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P211. |
| Zhao L., Wong M.C. , Li B., Li W., Zhu N. , Wu L.X. and Yam V.W.W. , Luminescent Amphiphilic 2,6-Bis(1-alkylpyrazol-3-yl)pyr idyl Platinum(II) Complexes: Synthesis, Characterization, Electrochemical, Photophysical, and Langmuir-Blodgett Film Formation Studies, Chemistry - A European Journal . 2010, 16: 6797-6809. |
| Zhao L., Wong M.C. , Li B., Li W., Wu L.X. and Yam V.W.W. , Luminescent Amphiphilic Platium(II) Complexes – Synt hesis, Characterization, Photophysical and Langmuir-Blodgett Film Formation Studies, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P212. |
| Researcher : Wong MK |
| List of Research Outputs |
| Liu Y. , Lok C.N. , Ko C.B. , Shum Y.T. , Wong M.K. and Che C.M. , Subcellular Localization of a Fluorescent Artemisinin Derivative to Endoplasmic Reticulum, Organic Letters . 2010, 12: 1420-1423. |
| Wang M. , Zhou C. , Wong M.K. and Che C.M. , Ruthenium-catalyzed Alkylation of indoles with Tertiary Amines by Oxidation of a sp 3 C-H Bond and Lewis Acid Catalysis, Chemistry - A European Journal . 2010, 16: 5723-5735. |
| Researcher : Wong WT |
| Project Title: | Coordination polymers of transition metals and lanthanide metals |
| Investigator(s): | Wong WT |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 11/2003 |
| Abstract: |
| To establish new synthetic routes to metal coordination polymers; to investigate the 3-D structures of these new metal containing polymers; to study the small molecule inclusion properties of these materials. |
| Project Title: | Relaxometric and stability studies of binuclear gadolinium complexes of cyclic polyaminocarboxy late ligands |
| Investigator(s): | Wong WT |
| Department: | Chemistry |
| Source(s) of Funding: | Collaborative Research Fund (CRF) - General Award |
| Start Date: | 03/2004 |
| Abstract: |
| This project aims at developing new binuclear gadoliniu m (Gd) complexes with high water proton relaxivity, good thermodynamic stability, and high in vivo specificity. |
| Project Title: | Synthesis and properties of lanthanide polyamido complexes |
| Investigator(s): | Wong WT |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 11/2004 |
| Abstract: |
| To establish new synthetic methods to lanthanide complexes containing amido ligands; to characterize these new compounds by spectroscopic and crystallograph ic methods; to investigate the chemical and photochemical properties of these new materials. |
| Project Title: | Luminescent Europium and Terbium Complexes for Ion Sensing |
| Investigator(s): | Wong WT |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 08/2007 |
| Abstract: |
| To synthesize and characterize new europium and terbium complexes that contain functionalized multidentate or macrocyclic ligands. To study the luminescent behaviors of these new complexes in ionic media. To examine the suitability of these complexes for ion sensing in different pH ranges. |
| Project Title: | Outstanding Researcher Award 2007-2008 |
| Investigator(s): | Wong WT |
| Department: | Chemistry |
| Source(s) of Funding: | Outstanding Researcher Award |
| Start Date: | 10/2008 |
| Abstract: |
| The Awards are intended to recognize, reward, and promote exceptional research accomplishments of academ ic and research staff. |
| List of Research Outputs |
| Cheung K.C., Guo P., So M.H., Lee L.Y.S., Ho K.P., Wong W.L., Lee K.H., Wong W.T. , Zhou Z.Y. and Wong K.Y., Electrocatalytic Reduction of Carbon Dioxide by A Polymeric Film of Rhenium Tricarbonyl Dipyridylamine, Journal of Organometallic Chemistry . 2009, 694: 2842-2845. |
| Guo J.F., Wang X.T., Wang B.W., Xu G.C., Gao S., Sze-To L. , Wong W.T. , Wong W.Y. and Lau T.C., One-Dimensional Ferromagnetically Coupled Bimetallic Chains Constructed with trans -[Ru(acac) 2 (CN) 2 ] - :Syntheses, Structures, Magnetic Properties, and Density Functional Theoretical Study, Chemistry - A European Journal . 2010, 16: 3524-3535. |
| Guo J.F., Yeung W.F., Lau P.H., Wang X.T., Gao S., Wong W.T. , Chui S.Y. , Che C.M. , Wong W.Y. and Lau T.C., trans- [Os III (salen)(CN) 2 ] __ : A New Paramagnetic Building Block for the Construction of Molecule-Based Magnetic Materials, Inorganic Chemistry . 2010, 49: 1607-1614. |
| Leung C.F., Yiu D.T.Y., Wong W.T. , Peng S.M. and Lau T.C., Synthesis and Reactivity of Osmium (VI) Nitrido Complexes Containing Pyridine-carboxylato Ligands, Inorganica Chimica Acta . 2009, 362: 3576-3582. |
| Man W.L., Lam W.W.Y., Kwong H.K., Peng S.M., Wong W.T. and Lau T.C., Reaction of a (Salen)ruthenium(VI) Nitrido Complex with Thiols. C-H Bond Activation by (Salen)ruthenium(IV) Sulfilamido Species, Inorganic Chemistry . 2010, 49: 73-81. |
| Shi B., Merten S., Wong D.K.Y., Chu C.K. , Liu L.L. , Lam S.K. , J ä ger A., Wong W.T. , Chiu P. and Metz P., The Rhodium-Catalyzed Carbene Cyclization Cycloaddition Cascade Reaction of Vinylsulfonates, Advanced Synthesis and Catalysis . 2009, 351: 3128-3132. |
| Wong W.T. , Co-Editor of Acta Crystallographica Section E (2006-2010), International Union of Crystallography . 2009. |
| Wong W.T. , Member of Editorial Advisory Board (2007-2010), Research Letters in Inorganic Chemistry, Hindawi Publishing . 2009. |
| Wong W.T. , Member of Editorial Advisory Board (2006-2010) , Current Chemical Biology, Bentham Science Publishers . 2009. |
| Wong W.T. , Member of Editorial Advisory Board (2006-2010), European Journal of Inorganic Chemistry, VCH-Wiley Publishers . 2009. |
| Wong W.T. , Member of Editorial Advisory Board (2006-2010), Journal of Cluster Science, Plenum Publishing . 2009. |
| Wong W.T. , Member of Editorial Advisory Board (2007-2010), Open Journal of Crystallography, Bentham Science Publishers . 2009. |
| Wong W.T. , Member of Editorial Advisory Board (2007-2010), Open Journal of Inorganic Chemistry, Bentham Scie nce Publishers . 2009. |
| Wong W.T. , Member of Editorial Advisory Board (2007-2010), Open Journal of Structural Biology, Bentham Science Publishers . 2009. |
| Wong W.T. , Member of Editorial Advisory Board (2009-2010), Polyhedron, Elsevier Publisher . 2009. |
| Yeung C.T., Lee W.S., Tsang C.S., Yiu S.M., Wong W.T. , Wong W.Y. and Kwong H.L., Chiral C 1 -symmetric 2,2':6',2'' -terpyridine ligands: Synthesis, Characterization, Complexation with Copper(II), Rhodium(III) and Ruthenium(II) ions and use of the Complexes in Catalytic Cyclopropanation of Styrene, Polyhedron . 2010, 29: 1497-1507. |
| Researcher : Wu P |
| List of Research Outputs |
| Wu P. , Biomolecules Sensing and Anti-cancer Studies of uminescent Platinum(II) Complexes with Tridentate and Tetradentate Ligands (PhD Thesis) . 2009. |
| Wu P. , Ma D.L. , Leung C.H. , Yan S.C., Zhu N. , Abagyan R. and Che C.M. , Stabilization of G-Quadruplex DNA with Platinum(II) Schiff-base Complexes: Luminescent Probe and Down Regulation of c-myc Oncogene Expression., Chemistry - A European Journal . 2009, 15: 13008-13021. |
| Researcher : Wu R |
| List of Research Outputs |
| Wu R. and Fung Y.S. , Determination of Lactoferrin and b -lactoglobulin in Dairy Products by Microflui dic-Chip Capillary Electrophoresis, Abstract of the 9th Asia-Pacific International Symposium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chi p (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P4-10: pp238. |
| Wu R. , Fung Y.S. and Yeung W.S.B. , Microfluidic-chip Capillary Electrophoresis for Analysis of Clinical Urinary Protenis , Abstract, 25th International Symposium on Microscale Bioseparations (MSB 2010), March 21-25, 2010, Prague, Czech Republic . 2010, P136, pp129. |
| Researcher : Xia H |
| List of Research Outputs |
| Xia H. , Ng S.M. , Kung H.F. and Lin M.C. , Inhibitory Effects of miR-200a on Nasopharyngeal Carcinoma Cell Growth, Migration and Invasion are Mediated by Different Targets, ASCB 49th Annual Meeting - December 5-9, 2009, San Diego, CA, USA. . 2009, 421. |
| Xia H. , Ng S.M. , Jiang S.S., Cheung K.C. , Sze J. , Bian X.W., Kung H.F. and Lin M.C. , miR-200a-mediated Downregulation of ZEB2 and CTNNB1 Differentially Inhibits Nasopharyngeal Carcinoma Cell Growth, Migration and Invasion, Biochemical and Biophysical Research Communications . 2009, 391(1): 535-541. |
| Researcher : Xia W |
| List of Research Outputs |
| Cheng T. , Li H. , Xia W. and Sun H. , Structure and function study of SlyD in Helicobacter pylori , 21st IUBMB and 12th FAOBMB International Congress of Biochemistry and Molecular Biology, Shanghai, China, August 2-7 . 2009. |
| Xia W. , Li H. , Sze K.H. and Sun H. , Structure of a nickel chaperone, HypA from Helicobacter pylori reveals two distinct metal binding sites, Journal of American Chemical Society . 2009, 131: 10031-10040. |
| Xia W. , Li H. , Sze K.H. and Sun H. , The Bifunctional Roles of Nickel Ions in Helicobacter pylori [NiFe] - Hydrogenase Maturation Pathway, , Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic Uni versity, Hong Kong, April 24, 2010 . I-78. |
| Researcher : Xia W |
| List of Research Outputs |
| Cheng T. , Li H. , Xia W. and Sun H. , Structure and function study of SlyD in Helicobacter pylori , 21st IUBMB and 12th FAOBMB International Congress of Biochemistry and Molecular Biology, Shanghai, China, August 2-7 . 2009. |
| Xia W. , Li H. , Sze K.H. and Sun H. , Structure of a nickel chaperone, HypA from Helicobacter pylori reveals two distinct metal binding sites, Journal of American Chemical Society . 2009, 131: 10031-10040. |
| Xia W. , Li H. , Sze K.H. and Sun H. , The Bifunctional Roles of Nickel Ions in Helicobacter pylori [NiFe] - Hydrogenase Maturation Pathway, , Seventeenth Symposium on Chemistry Postgraduate Research in Hong Kong, The Hong Kong Polytechnic University, Hong Kong, April 24, 2010 . I-78. |
| Researcher : Xiang H |
| List of Research Outputs |
| Xu Z. , Xiang H. , Vellaisamy A.L.R. , Chui S.Y. , Wang Y., Lai P.T. and Che C.M. , Organic field-effect transistors fabricated with N,N'-substituted dialkyl-1,3,8,10-tetramethylquinacridone compounds, Applied Physics Letters . 2009, 95: 123305. |
| Researcher : Xiang S |
| List of Research Outputs |
| Liu P. , Zhou C. , Xiang S. and Che C.M. , Highly Efficient Oxidative Carbon-carbon Coupling with SBA-15-support Iron Terpyridine Catalyst, Chemical Communications . 2010, 46: 2739-2741. |
| Researcher : Xing D |
| List of Research Outputs |
| Xing D. and Yang D. , Gold(I)-Catalyzed Highly Regio- and Stereoselective Decarboxylative Amination of Allylic N-Tosylcarbamates via Base-Induced Aza-Claisen Rearrangement in Water, Organic Letters . 2010, 12: 1068-1071. |
| Xing D. and Yang D. , Gold(I)-Catalyzed Highly Regio- and Stereoselective Decarboxylative Amination of Allylic N-Tosylcarbamates, The 239th American Chemical Society National Meeting, San Francisco, U.S.A., March 1, 2010 . |
| Researcher : Xu Z |
| List of Research Outputs |
| Xu Z. , Ng S.M. and Lin M.C. , Cell Cycle-Related Kinase Phosphorylates Casein Kinase Beta in Glioblasoma Cells, ASCB 49th Annual Meeting; December 5-9, 2009, San Diego, CA, USA. . 2009, 1017. |
| Xu Z. , Xiang H. , Vellaisamy A.L.R. , Chui S.Y. , Wang Y., Lai P.T. and Che C.M. , Organic field-effect transistors fabricated with N,N' -substituted dialkyl-1,3,8,10-tetramethylquinacridone compounds, Applied Physics Letters . 2009, 95: 123305. |
| Researcher : Xu Z |
| List of Research Outputs |
| Xu Z. , Ng S.M. and Lin M.C. , Cell Cycle-Related Kinase Phosphorylates Casein Kinase Beta in Glioblasoma Cells, ASCB 49th Annual Meeting; December 5-9, 2009, San Diego, CA, USA. . 2009, 1017. |
| Xu Z. , Xiang H. , Vellaisamy A.L.R. , Chui S.Y. , Wang Y., Lai P.T. and Che C.M. , Organic field-effect transistors fabricated with N,N'-substitute d dialkyl-1,3,8,10-tetramethylquinacridone compounds, Applied Physics Letters . 2009, 95: 123305. |
| Researcher : Xue J |
| List of Research Outputs |
| Cao Q., Guan X. , George M.W., Phillips D.L. , Ma C. , Kwok W.M., Li M. , Du Y. , Sun X.Z. and Xue J. , Ultrafast Time-resolved Transient Infrared and Resonance Raman Spectroscopic Study of the Photo-deprotection and Rearrangement Reactions of p -Hydroxyphenacyl Caged Phosphates, Faraday Discuss . 2010, 145: 171-183. |
| Du Y. , Xue J. , Li M. , Guan X. , McCamant D.W. and Phillips D.L. , Unravelling the Reaction Mechanism for the Fast Photocyc lisation of 2-Benzoylpyridine in Aqueous Solvent by Time-Resolved Spectroscopy and Density Functional Theory Calculations, Chemistry - A European Journal . 2010, 16: 6967-6972. |
| Li M. , Du Y. , Chuang Y.P. , Xue J. and Phillips D.L. , Water Concentration Dependent Photochemistry of Ketoprof en in Aqueous , Physical Chemistry Chemical Physics . 2010, 12: 4800-4808. |
| Researcher : Yam CY |
| Project Title: | Quantum chemistry simulation of chemical reaction in condensed media |
| Investigator(s): | Yam CY, Chen G |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 12/2007 |
| Abstract: |
| Chemical reaction dynamics has been an important field during the last few decades. The development in this field has greatly enhanced our understanding of the nature of bimolecular and unimolecular chemical reactions, and intermolecular and intramolecular energy transfer processes. The fast growing computing power and the development of sophisticated quantum and statistical methods in this research field allow us now to study complicated chemical processes quantitatively. I propose to study chemical reactions by employing the followi ng numerical methods: 1) Linear-scaling quantum mechanical method, Localized Density Matrix (LDM) method. 2) Time dependent density functional theory for open system combined with non-equilibrium Green’s function technique. 3) Electron-nuclear dynamics. |
| List of Research Outputs |
| Zheng J. , Zheng X. , Yam C.Y. and Chen G. , Computer Simulation of Feynman’s Ratchet and Pawl System , Physical Review E . 2010, 81: 061104-1 to 061104-15. |
| Researcher : Yam VWW |
| Project Title: | Synthesis and aggregation studies of Platinum(II) complexes in various media and envir onments |
| Investigator(s): | Yam VWW |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 08/2003 |
| Abstract: |
| To design, synthesize, and characterize various tridentate organic ligands; to incorporate the newly synthesized ligands into platinum metal centres and to characterize the metal complexes formed; to investigat e the spectroscopic, electronic absorption, emission, and electrochemical properties of these platinum (II) complexes; to study the aggregation behaviour of these complexes in various solvent environments and microenvironments and to investigate the effects of environments on the electronic absorption and emission properties of these metal complexes; to explore and assess their potential for application as reporter of various environments. |
| Project Title: | Design and synthesis of novel classes of luminescent transition metal complexes of functionali zed imidazole and N-heterocyclic carbene ligands and their related imidazolium salts |
| Investigator(s): | Yam VWW |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 09/2006 |
| Completion Date: | 08/2009 |
| Abstract: |
| (1) To design, synthesize, and characterize various functionalized imidazole-containing ligands and imidazoli um salts, (2) To incorporate the newly synthesized imidazole-containing ligands into selected metal centres and to characterize the metal complexes formed, (3) To utilize the various functionalized imidazolium salts as precursors for the synthesis of functional N-heterocyclic carbene complexes of selected metals and to characterize them, (4) To investigate the electronic absorption, luminescence and functional properties of the newly synthesized imidazole-containing ligands and imidazolium salts and their metal complexes, (5) To correlate their optical, luminescence and functional properties with the elect ronic and structural aspects of the ligands, salts and complexes, and to explore their potential for applications as molecular functional materials. (6) Impact: There has been a growing interest in the rational design and synthesis of advanced materials with unique properties for technological developments. Despite numerous works on N-heterocyclic carbenes (NHCs) and their metal complexes, most of the studies were focused on their structure and bonding, and their catalytic functions and reactivities, with the utilization of these classes of compounds, as well as their related imidazoles and their imidazol ium salts, as novel materials for other functions much less explored. Although there have been some recent reports on the luminescence properties of metal carbenes and the liquid crystalline properties of metal complexes of imidazoles and imidazolium salts, the work is still rather limited and relatively underdeveloped and unexplo red. Thus it is the aim of this project to design and synthesize novel classes of transition metal complexes of functionalized imidazole and NHC ligands and their related imidazol ium salts, to study their functional properties, and to explore their potential as new classes of molecular functional materials. It is envisaged that with appropriate design and introduction of various functional groups into the imidazole ligands and imidazolium precursors, novel classes of transition metal complexes with interes ting functional properties could be generated. We believe that the strong sigma-donating properties of the NHCs would give rise to metal complexes with rich luminescence properties, and an exploration into the luminescence behaviour, nonlinear optical (NLO) properties, and electronic communication and interaction of these imidazol e-based systems would yield interesting and novel findings. (7) In addition, the metal NHCs with the strong metal-carbon bond, which unlike the metal phosphines, are believed to be less susceptible to photodissociation reactions. These, together with the less interfering ligand-centred chromophoric behaviour of the NHC moiety, would make them suitable candidates for the exploration of the photophysical and luminescence properties of their metal complexes. The present project should contribute not only to the basic understanding of the optical, luminescence and photochromic behaviour of the newly synthesized molecules and metal complexes, but also would represent a new research initiative and direction towards the design and discovery of new classes of metal-containing molecular materials capable of exhibi ting rich functional properties. |
| Project Title: | Synthesis, aggregation and self-assembly of luminescent functional molecules - from solutions to polymers, ordered thin films, inorganic-organic hybrids, and supramolecular and nano-assemblies |
| Investigator(s): | Yam VWW, Wu LX, Wong MC, Shen JC |
| Department: | Chemistry |
| Source(s) of Funding: | NSFC/RGC Joint Research Scheme |
| Start Date: | 01/2007 |
| Abstract: |
| To design, synthesize, and characterize various functionalized organic molecules, donor ligands, polymers and nanoparticles; to incorporate the newly synthesized donor ligands into selected metal centres and to characteri ze the metal complexes formed; to investigate the spectroscopic, electronic absorption and photoluminescence properties of the newly synthesized functionalized organic molecules, metal complexes, polymers and nanoparticles; to study the spectroscopic properties and the aggregation behaviour of these molecules and metal complexes in polymers, ordered thin films, inorganic-organic hybrids, and supramolecular and nano-assemblies; to explore their potential function as optically addressable and luminescence functional materials, switches and probes of micro-en vironmental and conformational changes. |
| Project Title: | Design and Synthesis of Novel Classes of Luminescent Transition Metal Complexes and the Study of Their Properties Associated With Induced Conformation Changes |
| Investigator(s): | Yam VWW |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 10/2007 |
| Abstract: |
| To design, synthesize, and characterize various organic molecules and ligands capable of conformational changes, To incorporate the newly synthesized ligands into selected metal centres and to characterize the metal complexes formed, To study the electronic absorption, luminescence and 1H NMR spectroscopic properties of the newly synthesized organic molecules and ligands and their metal complexes and to investigate the properties associated with the induced conformation changes, To correlate their measured spectroscopic, optical and electronic properties with the structural and electronic aspects of the ligands and the metal complexes, and to explore their potential for applications as advanced materials with conformation-gateable capabilities. |
| Project Title: | Distinguished Research Achievement Award 2006-2007 |
| Investigator(s): | Yam VWW |
| Department: | Chemistry |
| Source(s) of Funding: | Distinguished Research Achievement Award |
| Start Date: | 12/2007 |
| Abstract: |
| Nil |
| Project Title: | Molecular Materials |
| Investigator(s): | Yam VWW |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding for Strategic Research Theme |
| Start Date: | 06/2008 |
| Completion Date: | 05/2011 |
| Abstract: |
| n/a |
| Project Title: | Design and Synthesis of Novel Classes of Luminescent Transition Metal Complexes with Metal-Metal Interactions and the Utilization of Their Associated Spectroscopic Properties as Probes and Reporters of Ion and Substrate Binding |
| Investigator(s): | Yam VWW |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 10/2008 |
| Abstract: |
| 1) To design, synthesize, and characterize various functionalized organic ligands and polymers, 2) To incorporate the newly synthesized ligands into selected metal centres of gold and platinum and to characterize the metal complexes formed, 3) To investigate the spectroscopic, electronic absorption and luminescence properties of the newly synthesized metal complexes, 4) To study the effect of ion and substrate binding on the electronic absorption and luminescence properties of the metal complexes, and 5) To correlate their measured spectroscopic properties with metal-metal interactions and the structural and electronic aspects of the ligands and the metal complexes, and to explore the potential utilization of these metal complexes as colorimetric and luminescent probes and reporters of ion and substrate binding. |
| Project Title: | Development of Gold(III)-contain ing Triplet Light-emitting Materials and Their Application Studies in the Fabrication of OLEDs and WOLEDs |
| Investigator(s): | Yam VWW, Chan MY, Wong MC |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Support Programme (Tier 3) |
| Start Date: | 11/2008 |
| Completion Date: | 04/2010 |
| Abstract: |
| The present project is built on the successful discovery by the Principal Investigator (PI) of a novel class of luminescent gold(III) complexes that show strong room-temperature phosphorescence in a recent RGC CERG-funded project. This stems from the fundamental understanding of the PI in the design, synthesis and spectroscopic properties of phosphorescent metal complexes. As it is apparent that a major breakthrough in recen t years involves the utilization of luminescent organometallic and metal complexes that can harvest energy from triplets and thus optimize emission efficiencies, the search for and discovery of new patentable classes of metal-orga nic triplet-emitting materials would represent an important area of focus in order to advance the development of these metal-organic phosphorescent materials for OLED applications. Despite recent interest in the exploration of electrophosphorescent materials, in particular metal complexes with heavy metal centres, most of the works are focused on those of iridium(III), platinum(II) and ruthenium(II) with other metal centres relatively less extensively explored. Since gold is a heavy metal centre and its complexes have also been shown to display rich luminescence behaviour, an exploration into the possible utilization of gold-based metal-organic materials in OLED and WOLED application studies would represent a challenging and worthwhile area of research. As a number of gold complexes have been shown by us to exhibit rich luminescence behaviour, an exploration into their application in OLED and WOLED fabrication would open up new classes of electrophosphorescent materials. It is also worth noting that in contrast to the isoelectron ic platinum(II) compounds which are known to show rich luminescence properties, very few examples of luminescent gold(III) compounds have been reported, probably due to the presence of low-energy d-d ligand field (LF) states and the electron deficient nature of the gold(III) metal centre. We demonstrated that introduction of strong donor ligands, such as alkynyl, into gold(III) compounds would enhance the luminescence properties as a result of the raising of the d-d ligand field (LF) excited states. Thus in the proposed project, attempts will be made to design and synthesize various gold-based molecular compounds, particularly the gold(III) alkynyl derivatives, and to study their electronic absorption, photoluminescence (PL), electrochemical and electroluminescence (EL) behaviour. Systematic variation of the ligands and the gold complexes will be made to fine-tune their spectroscopic and PL properties and to optimize their EL performance for OLED and WO LED applications. The exploitation of gold-containing compounds is believed to be advantageous given the relatively lower cost of gold than the more widely employed iridium and platinum metals and its promising phosphorescent properties that are very much underdeveloped. The main objectives of this project are: (1) to design and synthesize gold(III) complexes as triplet light-e mitting materials and to generate a small library of gold(III) phosphors, (2) to study their photoluminescence (PL) and electroluminescence (EL) properties, and (3) to fabricate and optimize OLEDs and WOLEDs based on the gold(III) phosphors. It is envisaged that the work will have important implications in the innovation and technology development of organic optoelectronics for display industry and in the development of WOLEDs for solid-state lighting, given their importance in energy and environmental development. Thus the technology will no doubt be of great benefit to both local and international display and lighting industries. |
| Project Title: | Design and Synthesis of Boron(III) and Zinc(II) Derivatives with Photoswitchable Colour and Luminescence Capabilities |
| Investigator(s): | Yam VWW |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 04/2009 |
| Completion Date: | 03/2010 |
| Abstract: |
| With the growing interest in the search for new advanced materials with novel and improved properties, a variety of investigations into molecular materials have emerged due to their synthetic versatility and ease of modification and functionalization. Boron and boron derivatives were proved to be an indispensable class of compounds in industry. They are utilized as dopants in the semiconductor industry, in the manufacture of light structural materials and preservatives, and as reagents in organic synthesis. Chemically, boron is electron-deficient and possesses a vacant p-orbital. It is an electrophile and a Lewis acid, readily bonded to electron-rich frameworks. Early works on boron chemi stry have mainly focused on their reactivity studies and their use as reagents for organic synthesis. It was only quite recently that the spectroscopic properties of boron derivatives have received much attention. One of the most important areas of interest for boron-containing π-conjugated systems in the past decades is their pot ential application as a new class of materials in optoelectronics. This class of compounds has also been shown to exhibit good electron-transporting properties. π-Conjugated organoboron polymers have also been synthesized and shown to exhibit strong blue emission and possess uniqu e conducting properties. A number of boron derivatives have also been demonstrated to show strong fluorescence properties. The most famous class is the 4,4-difluoro-4-bora-3a,4a-d iaza-s-indacene (BODIPY) derivatives that emit strongly with high fluorescenc e quantum efficiencies. Recent works by various groups have also directed their interests in preparing luminescent boron(III) derivatives of quinolinates based on the well-known photoluminescence and electroluminescence behaviour of the tris(8-hydroxy-quinolinato)aluminum(III) (Alq3), a heavier congener of boron in the same group of the Periodic Table. Other N,O-, N,N-, and O,N,O-tridentate chelates of boron(III) have also been synthesized and shown to exhibit good electron-transporting and strong emissive and electroluminescence properties. Various color OLEDs and WOLEDs have also been successfully fabricated. Apart from boron(III) derivatives of these chelates, quinolinates and other N,O- and N,N- chelat es of zinc(II) have been shown to exhibit intense luminescence. Utilization of zinc(II) chelates in the fabrication of OLEDs and WOLEDs has been reported; some of which also showed improved electron-transporting properties. While extensive efforts have been made recently to explore the photoluminescence and electroluminescence properties of new classes of boron(III) derivatives, most of them are concentrated on the design and development of fluorescent materials for use as strong emitters or electron-tran sporting materials in OLEDs for materials science development or as fluorescent labels, imaging agents or sensors in biomolecular diagnostics for biomedical applications. Despite a growing interest in the development of multifunct ional materials, the utilization of boron(III) compounds that show promising luminescence properties in the development of multifunctional materials is scarce and rather underdeveloped. In particular, an exploration of luminescent boron(III) derivatives with photoswitchable functions would represent an interesting topic of researc h. Various photoswitches based on the diarylethene building block have been applied to control not only the absorption spectrum, but also various physical properties, such as electrical conductivity, refractive index and lumines cence. Among these outputs, luminescence is considered to be one of the most attractive owing to its ease of detection and the less demanding requirements of the equipment. In designing luminescence photoswitching materials, it is essential to provide a nondestructive read-out capability. In view of the fact that boron(III) compounds showed promising luminescence properties, the development of photoswitchable boron(III) compounds would represent a challenging area of research. It is believed that the incorporation of the diarylethene moieties into these compounds would give rise to an effective means of perturbing the colour and luminescence properties upon ring-opening and ring-closing processes. The synthesis, characterization, photophysics, and photochromic properties of a series of boron(III) compounds will be explored. In addition to the boron(III) compounds, with appropriate design and choice of the ligands, other luminescent compounds, such as zinc(II) compounds, which are also known to show strong luminescent properties, will also be explored. Thus, the incorporation of the diarylethene units into the zinc(II) compounds will also be studied. Similarly, incorporation of the photochromic diarylethene moiety into N,O- bidentate zinc(II) is anticipated to drastically alter their colour and luminescent properties by the ring-opening and ring-closing proc esses. Thus new classes of photoswitchable coloured and luminescent multifunctional materials would be developed. It is envisaged that the combined effects of incorporating moieties of photoswitchable colour and luminescence functions would lead to the generation of novel classes of multifunctional materials with controllable functions. Therefore the objective of this project is to design and synthesize new classes of boron(III) derivatives with photoswitchable colour and luminescence functions. Variation of the electronic and steric properties of the ligands will also be made to tune the photoswitchable colour and luminescence properties. Investigation of their luminescence and photoswitching properties and their structure-property relationships will also be made. Extension of the work to the isolation of zinc(II) derivatives will also be made. It is envisaged that with the appropriate design and judicious choice of the chelate ligands, novel classes of photoswitchable coloured and luminescent multifunctional materials could be obtained. |
| Project Title: | Development of Gold(III)-containing Triplet Light-emitting Materials and Their Application Studies in the Fabrication of OLEDs and WOLEDs |
| Investigator(s): | Yam VWW |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Fund Internship Programme |
| Start Date: | 06/2009 |
| Abstract: |
| The present project is built on the successful discovery by the Principal Investigator (PI) of a no vel class of luminescent gold(III) complexes that show strong room-temperature phosphorescence in a recent RGC CERG-funded project. This stems from the fundamental understanding of the PI in the design, synthesis and spectroscopic properties of phosphorescent metal complexes. As it is apparent that a major breakthrough in recent years involves the utilization of luminescent organo metallic and metal complexes that can harvest energy from triplets and thus optimize emission efficiencies, the search for and discovery of new patentable classes of metal-organic triplet-emitting materials would represent an important area of focus in order to advance the development of these metal-organic phosphorescent materials for OLED applications. Despite recent interest in the exploration of electrophosphorescent materials, in particular metal complexes with heavy metal centres, most of the works are focused on those of iridium(III), platinum(II) and ruthenium(II) with other metal centres relatively less extensively explored. Since gold is a heavy metal centre and its complexes have also been shown to display rich luminescence behaviour, an exploration into the possible utilization of gold-based metal-organic materials in OLED and WOLED application studies would represent a challenging and worthwhile area of research. As a number of gold complexes have been shown by us to exhibit rich luminescence behaviour, an exploration into their application in OLED and WOLED fabrication would open up new classes of electrophosphorescent materials. It is also worth noting that in contrast to the isoelectronic platinum(II) compounds which are known to show rich luminescence properties, very few examples of luminescent gold(III) compounds have been reported, probably due to the presence of low-energy d-d ligand field (LF) states and the electron deficient nature of the gold(III) metal centre. We demonstrated that introduction of strong donor ligands, such as alkynyl, into gold(III) compounds would enhance the luminescence properties as a result of the raising of the d-d ligand field (LF) excited states. Thus in the proposed project, attempts will be made to design and synthesize vario us gold-based molecular compounds, particularly the gold(III) alkynyl derivatives, and to study their electronic absorption, photoluminescence (PL), electrochemical and electroluminescence (EL) behaviour. Systematic variation of the ligands and the gold complexes will be made to fine-tune their spectroscopic and PL properties and to optimize their EL performance for OLED and WOLED applications. The exploitation of gold-containing compounds is believed to be advantageous given the relatively lower cost of gold than the more widely employed iridium and platinum metals and its promising phosphorescent properties that are very much underdeveloped. The main objectives of this project are: (1) to design and synthesize gold(III) complexes as triplet light-emit ting materials and to generate a small library of gold(III) phosphors, (2) to study their photoluminescence (PL) and electroluminescence (EL) properties, and (3) to fabricate and optimize OLEDs and WOLEDs based on the gold(III) phosphors. It is envisaged that the work will have important implications in the innovation and technology development of organic optoelectronics for display industry and in the development of WOLEDs for solid-state lighting, given their importance in energy and environmental development. Thus the techno logy will no doubt be of great benefit to both local and international display and lighting industries. |
| Project Title: | Development of Gold(III)-containing Triplet Light-emitting Materials and Their Application Studies in the Fabrication of OLEDs and WOLEDs |
| Investigator(s): | Yam VWW |
| Department: | Chemistry |
| Source(s) of Funding: | Innovation and Technology Fund Internship Programme |
| Start Date: | 06/2009 |
| Abstract: |
| The present project is built on the successful discovery by the Principal Investigator (PI) of a novel class of luminescent gold(III) complexes that show strong room-temperature phosphorescence in a recent RGC CERG-funded project. This stems from the fundament al understanding of the PI in the design, synthesis and spectroscopic properties of phosphorescent metal complexes. As it is apparent that a major breakthrough in recent years involves the utilization of luminescent organometallic and metal complexes that can harvest energy from triplets and thus optimize emission efficiencies, the search for and discovery of new patentable classes of metal-organic triplet-emitting materials would represent an important area of focus in order to advance the development of these metal-organic phosphorescent materials for OLED applications. Despite recent interest in the exploration of electrophosphorescent materials, in particular metal complexes with heavy metal centres, most of the works are focused on those of iridium(III), platinum(II) and ruthenium(II) with other metal centres relatively less extensively explored. Since gold is a heavy metal centre and its complexes have also been shown to dis play rich luminescence behaviour, an exploration into the possible utilization of gold-based metal-organic materials in OLED and WOLED application studies would represent a challenging and worthwhile area of research. As a number of gold complexes have been shown by us to exhibit rich luminescence behaviour, an exploration into their application in OLED and WOLED fabrication would open up new classes of electrophosphorescent materials. It is also worth noting that in contrast to the isoelectronic platinum(II) compounds which are known to show rich luminescence properties, very few examples of luminescent gold(III) compounds have been reported, probably due to the presence of low-energy d-d ligand field (LF) states and the electron deficient nature of the gold(III) metal centre. We demonstrated that introduction of strong donor ligands, such as alkynyl, into gold(III) compounds would enhance the luminescence properties as a result of the raising of the d-d ligand field (LF) excited states. Thus in the proposed project, attempts will be made to design and synthesize various gold-based molecular compounds, particularly the gold(II I) alkynyl derivatives, and to study their electronic absorption, photoluminescence (PL), electrochemical and electroluminescence (EL) behaviour. Systematic variation of the ligands and the gold complexes will be made to fine-tune their spectroscopic and PL properties and to optimize their EL performance for OLED and WOLED applications. The exploitation of gold-containing compound s is believed to be advantageous given the relatively lower cost of gold than the more widely employed iridium and platinum metals and its promising phosphorescent properties that are very much underdeveloped. The main objectives of this project are: (1) to design and synthesize gold(III) complexes as triplet light-emitting materials and to generate a small library of gold(III) phosphors, (2) to study their photoluminescence (PL) and electroluminescence (EL) properties, and (3) to fabricate and optimize OLEDs and WOLEDs based on the gold(III) phosphors. It is envisaged that the work will have important implications in the innovation and technology development of organic optoelectronics for display industry and in the development of WOLEDs for solid-state lighting, given their importance in energy and environmental development. Thus the technology will no doubt be of great benefit to both local and international display and lighting industries. |
| Project Title: | Design, Synthesis and Supramolecu lar Assembly of Novel Classes of Luminescent Gold(I) Complexes and the Study of Metallogels Derived from Gold(I) and Other Transition Metal-Ligand Chromophores |
| Investigator(s): | Yam VWW |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 10/2009 |
| Abstract: |
| 1) To design, synthesize, and characterize various functionalized organic donor ligands, 2) To incorporate the ligands into gold metal centre to give the gold precursor complexes and to characterize them, 3) To incorporate the chalcogen- and phosphorus-containing ligands into the gold precursor complexes to give the polynuclear gold(I)-chalcogen and phosphinidene complexes and to characterize them, 4) To design, synthesize and characterize other related mono- and dinuclear gold complexes and transition metal-ligand chromophoric complexes and to explore their supramolecular assembly and gelation properties, 5) To investigate the spectros copic, electronic absorption and luminescence properties of the newly synthesized metal complexes, 6) To study the effect of solvents and microenvironments on the spectroscopic, electronic absorption and luminescence properties of the metal complexes, and 7) To correlate the measured spectroscopic, electronic absorption and luminescence properties of the metal complexes with the nuclearities and nature of the metal centres, metal -metal interactions, structural and electronic aspects of the ligands, as well as their supramolecular assemblies and nanostructures. |
| Project Title: | Institute of Molecular Functional Materials |
| Investigator(s): | Yam VWW, Che CM, Tang BZ |
| Department: | Chemistry |
| Source(s) of Funding: | Areas of Excellence Scheme |
| Start Date: | 01/2010 |
| Abstract: |
| n/a |
| Project Title: | Design and Synthesis of Strongly Absorbing Photosensitizers for Dye-Sensitized Solar Cells |
| Investigator(s): | Yam VWW |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Basic Research |
| Start Date: | 03/2010 |
| Abstract: |
| With the growing interest in the search for new advanced materials with novel and improved properties, a variety of investigations into molecular materials have emerged due to their synthetic versatility and ease of modification and functionalization. With the upcoming depletion of fossil fuels and energy reserves, together with the increasing interest in the search for alternative carbon-neutral energy sources, there has been much attention in the exploration of solar energy as clean sources of renewable energy. Transition metal complex and polymeric photovoltaic (PV) cells show promise as low-cost, flexible devices for renewable sources of energy which have been extensively investigat ed during the past two decades. Recently, tremendous progress was made in the development of dye-sensitized solar cells (DSSCs) based on nanocrystallined TiO2 semiconductor and well-designed panchromatic dye with reported efficien cy as high as 11 %. In order to further enhance the efficiencies of the dye-sensitized solar cells, it is important to develop novel materials exhibiting a narrow optical gap and efficient charge transfer properties to harvest the majority of sunlight and efficiently transport the photogenerated charges to the counter electrodes. Dye-sensitized solar cells (DSSCs) are regenerative photo-electrochemical cells consisting of a photoanode, a platinized count er electrode and an electrolyte positioned between them. In this type of cells, the photoanode should contain a layer of semiconducting material (i.e. TiO2) on a conductive glass that can be sensitized by at least one panchromatic substance, like organic or inorganic dyes and these have been extensively investigated during the past decade. Within the cells, chromophoric materials, usually named photosensitizer, will form a monolayer on the semiconducting material, which can generate electrical energy by absorbing light of different wavelengths. The molecular engineering of the dye molecules should give rise to sensitizers that are panchromatic, i.e. they absorb light of all wavelengths. Ideally, all photons below a threshold wavelength of 900 nm should be harvested and converted to electricity in the ext ernal circuit. Tremendous progress has also been made in the development of dye-sensitized solar cells (DSSCs) based on nanocrystalline TiO2 semiconductor and well-designed panchromatic dye such as the black dye of formula [RuL(N CS)3]–, where L is the anchoring 4,4’,4”-tricarboxy-2,2’:6’,2”-terpyridine ligand with reported efficiency of as high as 10.4 %. The photochemistry of transition metal complexes with polypyridine ligands has been extensively inves tigated in the last few decades. With the advantages of possessing intense charge-transfer (CT) absorptions with large extinction coefficients, ease of tunability of redox properties and good charge transfer properties, transition metal complexes with polypyridyl ligands have attracted much attention for photovoltaic applications. Grätzel and co-workers have demonstrated the photo-electrochemical properties of the heteroleptic amphiphilic complexes of formula [RuL(NCS)3]–, where L is the anchoring 4,4’,4”- tricarboxy-2,2’:6’,2”-terpyrid ligand. With a high open circuit voltage (Voc = 0.72 V), a high short circuit current (Jsc = 20.53 mAcm–2) and a good fill factor value (FF = 0.74), this dye was shown to exhibit a relatively high conversion efficiency value of 10.4 %. A further remarkable increase in photovol taic performance was achieved by Grätzel and co-workers using the complex with formula [RuLL’(NCS)2], where L is the anchoring 4,4’-dicarboxy-2,2’-bipyridine ligand and L’ is 2,2’-bipyridine ligand with long alkyl chains. However, progress in optimizing dye-sensitized solar cells has been mainly focused on ruthenium-based sensitiz ers, partly due to the well-established photophysical and photochemical studies of the ruthenium(II) polypyridine system. Apart from the ruthenium(II) system, studies on the isoelectronic osmium(II), rhenium(I) and iridium(III) polypyridines have also been reported recently. While extensive efforts have been recently made to explore the photosensitizing properties of metal chromophoric dyes in dye-sensitized solar cells, most of them are concentrated on the design and development of the ruthenium(II) polypyridine system, with corresponding studies on the use of other metal complexes much less explored. Despite exploration of the photophysical properties of charge transfer complexes has been extended to metal complexes other than the d6 metal polypyridines, the utilization of these charge transfer compounds as sensitizers in DSSC development is scarce and rather unexplored. In particular, an exploration of non-ruthenium-based derivatives with photosensitizing functions would repre sent an interesting topic of research. In view of the fact that porphyrins and metal polypyridine compounds other than that of ruthenium also showed promising intense absorption properties in the visible to near-infrared region as well as rich excited state charge transfer properties, the development of photosensitizers based on these non-ruthenium-based chromophores would represent a challenging area of research. It is believed that the incorporation of the TiO2-anchoring groups into these compounds would give rise to an effective means of promoting the electron injection from these dyes into the semiconductor electrodes for dye-sensitized solar energy conversion work. The synthesis, characterization, optical, and photosensitizing properties of a series of non-ruthenium-based compounds will be explored. In addition to the metal polypyridine compounds, with appropriate design and choice of the ligands, other multi-chromophoric compounds, such as the linking together of porphyrins to non-ruthenium-based metal polypyridines, will also be explored. Their optical, redox and photose nsitizing behaviour will also be studied. Thus new classes of photosensitizing materials would be developed. It is envisaged that the combined effects of incorporating moieties of multiple chromophores with strong visible to near-infrared absorbing and photosensitizing functions would lead to the generation of novel classes of dyes for DSSCs. Therefore the objective of this project is to design and synthesize new classes of non-ruthenium-based derivatives with photosensitizing functions. Variation of the structural, electronic and excited state properties of the derivatives will also be made to tune the optical and photosensitizing properties. Investigation of their photosensitizing properties and their structure-property relationships will also be made. It is envisaged that with the appropriate design and judicious choice of the ligands, novel classes of multi-chromophoric photos ensitizers could be obtained. |
| Project Title: | Development of gold(III)-containing triplet light-emitting materials for phosphorescent organic light-emitting devices |
| Investigator(s): | Yam VWW, Chan MY, Wong MC, Lam SWH |
| Department: | Chemistry |
| Source(s) of Funding: | Seed Funding Programme for Applied Research |
| Start Date: | 06/2010 |
| Abstract: |
| Organic light-emitting devices (OLEDs) technology is emerging as a leading display technology that promi ses to revolutionize everything that uses displays from cellular phones, personal digital assistants (PDAs) and audio-video players, to computer monitors and high density televisions. With the great efforts on improving the device efficiency that meets the realistic requirement for commercial applications, OLEDs are also targeted as new generation of solid-state lighting source to dislodge the incandescent bulbs. Indeed, a number of display companies, such as Philips Lighting, Universal Display Corporation, Konica Minolta, have already put into effect the development of efficient OLED displays entering the market. In 2007, Sony has launched the world’s first 11” OLED-TV with a thickness of only 3 mm, and this has been made commercially available in Japan and the U.S. Because of the upsurge in demand for OLEDs, the investment and production have increased correspondingly, especially for the development of OLED materials. More recently, an industry analyst firm NanoMarkets forecasts the global market for OLE D materials will reach USD 2.7 billion by 2015. This not only creates opportunity for the large corporate, but also allows small companies to fill in the niches. The huge market potential of OLED materials urges the demand for the search of novel organic materials that are capable of exhibiting high photoluminescence (PL) quantum yield and tunable emission colors. Because of their superior performance in terms of efficiency, phosphorescent materials have attracted much attenti on over the past two decades. Particularly, the use of phosphorescent materials can harvest both the singlet and triplet excitons (generated at a ratio of 1:3 owing to their statistical spin population) generated by electrical injection, corresponding to a four-fold increase in internal quantum efficiency of up to a maximum of 100%. It is believed that the incorporation of heavy metal atoms into light-emitting materials can increase spin-orbit coupling and thereby facilitate the intersystem crossing from singlet to triplet excited states. Extensive studies have been carried out on the design and synthesis of novel phosphorescent materials; particularly, much research work have been directed to the iridium(III) and platinum(II) systems due to their ease of energy tuning via synthetic modification. On the other hand, the development of phosphorescent emitters with other metal centres that are less expensive and of a less toxic nature has been relatively less explored. One suitable candidate is the gold metal center that is well known for its inertness and low toxicity. In contrast to gold(I) and the isoelectronic platinum(II) compounds which are known to show rich luminescence properties, very few examples of luminescent gold(III) compounds have been reported, probably due to the presence of non-emissive low-energy d-d ligand field states and the electrophilicity of the gold(III) metal centre. More recently, the Principal Investigator (PI) first demonstrated the invention of an entirely new class of luminescent neutral cyclometalated alkynylgold(III) compounds, [Au(C^N^C)(CC-R)], that are photo-stable and are capable of displaying interesting PL propertie s which occur even at room temperature. It is envisaged that the introduction of strong donor ligands into gold(III) compounds can enhance the luminescence properties as a result of the enlargement of d-d splitting. More importantly, the alkynylgold(III) compounds show intense low-energy electronic absorption as well as emission bands in the visible range, which can be fine-tuned by the modification of substituents on the cyclometalated or alkynyl ligand. Such broader color-tuning possibility is comparable to cyclometalated iridium(III) complexes and superior to platinum(II), ruthenium(II) and osmium(II) systems. Taking the advantages that these cyclometal ated alkynylgold(III) compounds are neutral and are thermally stable, fabrication of OLEDs can be achieved by vacuum deposition of such luminescent compounds as phosphorescent emitters. Recent work by the PI showed that a yellow-e mitting OLED exhibited a high current efficiency of 36.6 cd/A, a power efficiency of 26.2 lm/W, and an external quantum efficiency of 11.5 %. These findings suggest that the alkynylgold(III) compounds are superior candidates as light-emitting materials in terms of the relatively inexpensive cost and non-toxic nature, compared to iridium, platinum and osmium complexes. Realization of these important findings give rise to important information and insights to the future design of new classes of phosphorescent emitters that are based on the gold(III) systems that exhibit high PL and tunable emission color capabilities. The proposed project aims to design and synthesize various gold(III)-containing compounds and to study their electronic absorption, PL, electrochemical and electroluminescence (EL) behaviour . Particularly, systematic variation of the ligands and the gold complexes will be attempted to fine-tune the emission colors that covers the entire visible range. More specifically, the objectives of this project are: 1. To design and synthesize a series of gold(III) complexes as triplet light-emitting materials by the modification of substituents on the cyclometalated or alkynyl ligand, 2. To characterize the gold(III) complexes using various spectroscopic techniques and to study their electronic absorption and PL properties in various media, 3. To study the highest occupied molecular orbital (HOMO ) and the lowest unoccupied molecular orbital (LUMO) energy levels of the gold(III) complexes using electrochemical techniques and density functional theory (DFT) calculations, 4. To fabricate and optimize the performance of OLEDs based on the gold(III) complexes as phosphorescent dopants, and 5. To develop design rules for developing gold(III) complexes with tunable PL properties. |
| List of Research Outputs |
| Au K.M. , Wong M.C. , Chen Z. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , A Novel Class of Bis-cyclometalated Alkynylgold(III) Complexes – Synthesis, Characterization, Photophysics, Electrochemistry and the First Observation of Electrogenerated Chemiluminescence, The 5th International Conference on Gold Science, Technology and its Applications (organized by World Gold Council), Heidelberg, Germany, July 26–29, 2009 . |
| Au K.M. , Wong M.C. , Zhu N. and Yam V.W.W. , Luminescent Cyclometalated N-Heterocyclic Carbene-Cont aining Organogold(III) Complexes: Synthesis, Characterization, Electrochemistry, and Photophysical Studies, Journal of the American Chemical Society . 2009, 131: 9076-9085. |
| Au K.M. , Chen Z. , Wong M.C. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , Synthesis, Characterization, Photophysical Studies, Electrochemistry and Electrogenerated Chemiluminescence of Bis-cyclometalated Alkynylgold(III) Complexes and their Applications in Organic Light-Emitting Devices, The 42 nd International Union of Pure and Applied Chem istry (IUPAC) Congress, Glasgow, United Kingdom, August 2-7, 2009 . P701_030. |
| Au K.M. , Chen Z. , Wong M.C. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , Synthesis, Characterization, Photophysical Studies, Electrochemistry and the First Observation of Electrogenerated Chemiluminescence of Bis-cyclometalated Alkynylgold(III) Complexes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P217. |
| Bennett M.A., Bhargava S.K., Cheng C.C. , Lam S.W.H. , Lee K.M. , Priv é r S.H., Wagler J., Willis A.C. and Yam V.W.W. , Unprecedented Near-Infrared (NIR) Emission in Diplatinum(III) (d 7 -d 7 ) Complexes at Room Temperature, Journal of the American Chemical Society . 2010, 132: 7094-7103. |
| Chan H.Y. , Lam J.W.Y., Wong M.C. , Tang B.Z. and Yam V.W.W. , Chiral Poly(4-ethynylbenzoyl-L-valine) Induced Helical Self-assembly of Platinum(II) Terpyridyl Complexes with Tunable UV-vis Absorption, Emission and Circular Dichroism Changes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P214. |
| Chan K.M.C. , Tao C.H. , Tam H.L., Zhu N. , Yam V.W.W. and Cheah K.W., Synthesis, Characterization, Luminescence and Non-linear Optical (NLO) Properties of Oxadiazole- and Truxene-Cont aining Platinum(II) Alkynyl Complexes with Donor-Acceptor Functionalities, The 42 nd International Union of Pure and Applied Chemistry (IUPAC) Congress, Glasgow, UK, August 2-7, 2009 . P701_46. |
| Chan K.M.C. , Tao C.H. , Tam H.L., Zhu N. , Yam V.W.W. and Cheah K.W., Synthesis, Characterization, Luminescence and Non-lin ear Optical Properties of Oxadiazole- and Truxene-containing Platinum(II) Alkynyl Complexes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P213. |
| He X. , Lam S.W.H. , Zhu N. and Yam V.W.W. , Design and Synthesis of Calixarene-Based Bis-alkynyl-Bridged Dinuclear Au 1 Isonitrile Complexes as Luminescent Ion Probes by the Modulation of Au···Au Interactions, Chemistry - A European Journal . 2009, 15: 8842-8851. |
| He X. , Zhu N. and Yam V.W.W. , Design and Synthesis of Calixarene-based Bis-alkynyl-bridged Dinuclear Au(I) Isonitrile Complexes as Luminescent Ion Probes via the Modulation of Au … Au Interactions, The 6 th National Conference on Coordination Chemistr y ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P218. |
| He X. and Yam V.W.W. , Design, Synthesis, Photophysics, and Ion-binding Studies of a Ditopic Receptor Based on Gold(I) Phosphine Thiolate Complex Functionalized with Crown Ether and Urea Binding Units, Inorganic Chemistry . 2010, 49: 2273-2279. |
| He X. , Cheng C.C. , Zhu N. and Yam V.W.W. , Selective Ion Probe for Mg 2+ Based on Au(I) ... Au(I) Interactions in Tripodal Alkynylgold(I) Complex With Oligoether Pendants, , Chemical Communications . 2009, 4016-4018. |
| He X. , Zhu N. and Yam V.W.W. , Synthesis, Characterization, Structure, and Selective Cu 2+ Sensing Studies of an Alkynylgold(I) Complex Containing the Dipicolylamine Receptor, Organometallics . 2009, 28: 3621-3624. |
| Ko C.C. and Yam V.W.W. , Transition Metal Complexes with Photochromic Ligands – Photosensitization and Photoswitchable Properties , Journal of Materials Chemistry . 2010, 20: 2063-2070. |
| Lam S.T. and Yam V.W.W. , Luminescent Metallogels and Functional Materials of Rhenium(I) Tricarbonyl Diimine Complexes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P215. |
| Lam S.T. , Zhu N. and Yam V.W.W. , Synthesis and Characterization of Luminescent Rhenium(I) Tricarbonyl Diimine Complexes with a Triarylboron Moiety and the Study of Their Fluoride Ion-Binding Properties, Inorganic Chemistry . 2009, 48: 9664-9670. |
| Lee K.M. , Cheng C.C. , Zhu N. and Yam V.W.W. , Novel Air-stable Hexanuclear Gold(I) Phosphinidene Complexes Containing Redox-active Ferrocenyl Units, The 5 th International Conference on Gold Science, Technology and its Applications (organized by World Gold Council),Heidelber g, Germany, July 26–29, 2009 . |
| Li Y.G., Wong M.C. , Tam A.Y.Y. , Wu L.X. and Yam V.W.W. , Thermo- and acid-responsive photochromic spironaphthox azine-containing organogelators, Chemistry - A European Journal . 2010, 8690-8698. |
| Song H.O., Chan T.W. , Li M. , Wong M.C. , Yam V.W.W. and Wu L.X., Synthesis, Characterization and Fluorescence Resonance Energy Transfer (FRET) Studies of Rhenium(I) Complexes With Coumarin Pendants, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P210. |
| Tam A.Y.Y. , Wong M.C. and Yam V.W.W. , Influence of Counter-Anion on the Chiral Supramolecular Assembly of Alkynylplatinum(II) Terpyridyl Metallogels that are Stabilized by Pt···Pt and p - p Stacking Interactions, 5th International Symposium on Macrocyclic and Supramolecul ar Chemistry . 2010. |
| Tam A.Y.Y. , Wong M.C. , Zhu N. , Wang G. and Yam V.W.W. , Luminescent Alkynylplatinum(II) Terpyridyl Metallogels Stabilized by Pt∙∙∙Pt, p - p , and Hydrophobic-Hydophobic Interactions , Langmuir . 2009, 25: 8685-8695. |
| Tam Y.Y. , Wong M.C. , Zhu N. and Yam V.W.W. , Luminescent Metallogel of Alkynylplatinum(II) Terpyri dyl Complexes: Interplay of Metal ... Metal, p - p and Hydrophobic-Hydrophobic Interactions on Gel Formation, , The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P216. |
| Tao C.H. and Yam V.W.W. , Branched Carbon-Rich Luminescent Multinuclear Platinum( II) and Palladium(II) Alkynyl Complexes With Phosphine Ligands, Journal of Photochemistry and Photobiology C: Photochemistry Reviews . 2009, 10: 130-140. |
| Tao C.H. , Zhu N. and Yam V.W.W. , Synthesis, Characterisation and Luminescence Propertie s of Carbazole-Containing Platinum(II) and Palladium(II) Alkynyl Complexes (invited article), Journal of Photochemistry and Photobiology A: Chemistry . 2009, 207: 94-101. |
| Wong H.L. , Ko C.C. , Lam S.W.H. and Yam V.W.W. , Design And Synthesis Of New Classes Of Photochromic Diarylethene-containing Heteroacenes And Their Switcha ble Luminescence Properties, The 13 th International Symposium on Novel Aromatic Compounds (ISNA-13), Luxembourg City, July 19 – 24, 2009 . 2009, SA028. |
| Wong H.L. , Ko C.C. , Lam S.W.H. , Zhu N. and Yam V.W.W. , Design and Synthesis of a New Class of Photochromic Diarylethene-Containing Dithieno[3,2-b:2’,3’-d]pyrroles and Their Switchable Luminescence Properties, Chemistry - A European Journal . 2009, 15: 10005-10009. |
| Wong M.C. , Lam S.W.H. , Zhou Z.Y. and Yam V.W.W. , A Luminescent Trinuclear Platinum(II) Pt 3 C 2 System Having a “Naked” C º C 2- Ligand Swapping Amongst Three Unsupported Platinum(II) Moieties, The 42 nd International Union of Pure and Applied Chemistry (IUPAC) Congress, Glasgow, UK, August 2-7, 2009 . P701_43. |
| Wong M.C. , Lam S.W.H. , Zhu N. , Zhou Z.Y. and Yam V.W.W. , Luminescent Polynuclear Alkynylplatinum(II) Complexes with p -Coordination of Various Metal Ions, , The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 (Oral presentation by Dr Keith Man-Chung Wong) . 2009. |
| Yam V.W.W. , Associate Editor (2008-2010), Inorganic Chemistry . 2009. |
| Yam V.W.W. , Chair of the Advisory Committee (2004-2010), Institute of Chemistry, Academia Sinica, Taipei, Taiwan . 2009. |
| Yam V.W.W. , Chairman of Organizing Committee, 6th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry), Hong Kong, P.R. China, July 6-9, 2009 . 2009. |
| Yam V.W.W. , Chairman of the Chemistry Technical Committee, The 5 th International Conference on Gold Science, Technology and its Applications (organized by World Gold Council), Heidelberg, Germany, July 26-29, 2009 . , 2009. |
| Yam V.W.W. , Councilor (2002-2010), Asian and Oceanian Photochemistry Association . 2009. |
| Yam V.W.W. , Country Representative of the Planning Committee (2002-present), International Conference on Coordination Chemistry (ICCC), Manchester, United Kingdom . 2009. |
| Yam V.W.W. , Design and Assembly Strategies Towards Luminescent Metal-based Molecular Materials, International Symposium on Macrocyclic and Supramolecular Conference (ISMSC 2010), Nara, Japan, June 6-10, 2010 (Invited Lecture) . 2010. |
| Yam V.W.W. , Design and Assembly Strategies Towards Photofunctional Materials, International Symposium on Chemical Conversion of Light Energy at the Annual Meeting of the Chemical Society of Japan, Osaka, March 26-29, 2010 (Plenary Lecture) . 2010. |
| Yam V.W.W. , Design and Assembly Strategies Towards Photofunctional Molecular Materials, International Workshop on Organic Photoswitchable Multifunctional Molecules and Materials, Shanghai, PR China, October 25-27, 2009 (Plenary Lecture) . 2009. |
| Yam V.W.W. , Director and Project Coordinator (2010-2017), Institute of Molecular Functional Materials [Supported by the University Grants Committee (UGC) Areas of Excellence (AoE) Scheme] . 2010. |
| Yam V.W.W. , Distinguished Alumni (Honoured at the 70 th Anniversary of the Faculty of Science), Faculty of Science, The University of Hong Kong . 2009. |
| Yam V.W.W. , Editorial Advisory Board (2005-2009), Chinese Journal of Inorganic Chemistry . 2009. |
| Yam V.W.W. , Editorial Advisory Board (2007-present), ACS Nano . 2009. |
| Yam V.W.W. , Editorial Board (2007-present), Chemical Journal of Chinese Universities . 2009. |
| Yam V.W.W. , Editorial Board (2008-2013), Science in China B: Chemistry . 2009. |
| Yam V.W.W. , Editorial Board (2010-2012), Philosophical Transactions of the Royal Society A - Mathematical, Physical and Engineering Sciences . 2010. |
| Yam V.W.W. , From Design to Assembly of Photofunctional Metal-Based Molecular Materials, International Symposium on Nano-Bio Molecular Assembl y 2010 (Post-conference of 5th International Symposium on Macrocyclic and Supramolecular Chemistry 2010), Seoul, Korea, June 15-17, 2010 (Invited Lecture) . 2010. |
| Yam V.W.W. , International Editorial Board (2004-present), Coordination Chemistry Reviews . 2009. |
| Yam V.W.W. , International Editorial Board (2005-present), Comments on Inorganic Chemistry . 2009. |
| Yam V.W.W. , International Editorial Board (2007-present), Gold Bulletin . 2009. |
| Yam V.W.W. , International Editorial Board (2008-present), Nano Research . 2009. |
| Yam V.W.W. , Luminescent Metal-Based Molecular Materials - From Fundamentals to Functions, 2 nd Asian Conference on Coordination Chemistry (2nd ACCC), Nanjing, PR China, November 1-4, 2009 (Keynote Lecture) . 2009. |
| Yam V.W.W. , Member of European Research Council (ERC) Advanced Grants Panel, Physical Sciences and Engineering Panel (2007-2013), European Research Council, Brussels, Belgium . 2009. |
| Yam V.W.W. , Member of the Academic Advisory Committee (2005-2010), Academia Sinica, Taipei, Taiwan . 2009. |
| Yam V.W.W. , Member of the Council of the Beijing National Laboratory for Molecular Sciences, Peking University-Institute of Chemistry, Chinese Academy of Sciences, Beijing, P.R. China . 2009. |
| Yam V.W.W. , Member of the International Advisory Board for the PRESTO on “Chemical Conversion of Light Energy”, Japan Science and Technology Agency, Tokyo, Japan . 2009. |
| Yam V.W.W. , Member of the International Advisory Board, The 42nd International Union of Pure and Applied Chemistry (IUPAC) Congress, Glasgow, United Kingdom, August 2-7, 2009 . 2009. |
| Yam V.W.W. , Member of the Search Committee for Directorship (2010), Institute of Chemistry, Academia Sinica, Taipei, Taiwan . 2010. |
| Yam V.W.W. , Molecular Design and Assembly Strategies Towards Photofunctional Materials, Department of Biology and Chemistry, City University of Hong Kong, April 21, 2010 (Invited Lecture) . 2010. |
| Yam V.W.W. , Molecular Design and Assembly Strategies Towards Photofunctional Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing, PR China, January 8, 2010 (Molecular Science Forum Lecture Professorship) . 2010. |
| Yam V.W.W. , Molecular Design and Assembly Strategies Towards Photofunctio nal Materials, The 42 nd International Union of Pure and Applied Chemistry (IUPAC) Congress, Glasgow, UK, August 2-7, 2009 (Plenary Lecture) . 2009. |
| Yam V.W.W. , Molecular Design and Assembly Strategies Towards Photofunctional Metal Complexes, Singapore International Chemical Conference 6 (SICC6) - Chemical Synthesis: Creativity and Applications, Singapore, December 15-18, 2009 (Keynote Lecture) . 2009. |
| Yam V.W.W. , Molecular Science Forum Lecture Professorship (2010), Institute of Chemistry, Chinese Academy of Sciences, Beijing, P.R. China . 2010. |
| Yam V.W.W. , Molecular Science Forum Lecture Professorship, Institute of Chemistry, Chinese Academy of Sciences . 2010. |
| Yam V.W.W. , Panel Member of the Evaluation Committee for the State Natural Science Award, National Organization of Science and Technology Awards (NOSTA), State Council, Beijing, P.R. China . 2010. |
| Yam V.W.W. , Philip Wong Wilson Wong Professorship in Chemistry and Energy, The University of Hong Kong . 2010. |
| Yam V.W.W. , Hu Y. , Chan H.Y. and Chung Y.S.C. , Reversible pH- and Solvent-Responsive Micelle-Mediated Self-Assembly of Platinum(II) Terpyridyl-Based Metallo-Sup ramolecular Diblock Copolymers, Chemical Communications . 2009, 6216-6218. |
| Yam V.W.W. , Song H. , Chan T.W. , Zhu N. , Tao C.H. , Wong M.C. and Wu L.X., Synthesis, Characterization, Ion-Binding Properties, and Fluorescence Resonance Energy Transfer Behavior of Rhenium(I) Complexes Containing a Coumarin-Appended 2,2′-Bipyridine, Journal of Physical Chemistry C . 2009, 113: 11674-11682. |
| Yin Z.D., Tao C.H. , Wong M.C. , Yam V.W.W. and Wu L.X., A Novel Bodipy-based Probe and its Magnesium Ion-responsive Spectra, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistr y) Hong Kong, P.R. China, July 6-9, 2009 . P211. |
| Zhang R.X., Tang D., Lu P., Yang X.Y., Liao D.L., Zhang Y.J., Zhang M.J., Yu C. and Yam V.W.W. , Nucleic Acid-Induced Aggregation and Pyrene Excimer Formation, Organic Letters . 2009, 11: 4302-4305. |
| Zhao L., Wong M.C. , Li B., Li W., Zhu N. , Wu L.X. and Yam V.W.W. , Luminescent Amphiphilic 2,6-Bis(1-alkylpyrazol-3-yl)pyridyl Platinum(II) Complexes: Synthesis, Characterization, Electrochemical, Photophysical, and Langmuir-Blodgett Film Formation Studies, Chemistry - A European Journal . 2010, 16: 6797-6809. |
| Zhao L., Wong M.C. , Li B., Li W., Wu L.X. and Yam V.W.W. , Luminescent Amphiphilic Platium(II) Complexes – Synthesis, Characterization, Photophysical and Langmuir-Blodgett Film Formation Studies, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P212. |
| Researcher : Yan J |
| List of Research Outputs |
| Ho C.M. , Zhang J.L., Zhou C. , Chan O.Y. , Yan J. , Zhang F.Y., Huang J.S. and Che C.M. , A Water-Soluble Ruthenium Glycosylated Porphyrin Catalyst for Carbenoid Transfer Reactions in Aqueous Media with Applications in Bioconjugation Reactions, Journal of the American Chemical Society . 2010, 132: 1886-1894. |
| Lee P.Y. , Zhu Y. , Yan J. , Sun R.W.Y. , Hao W. , Liu X.L., Che C.M. and Wong K.K.Y. , The cytotoxic effects of lipidic formulated gold-porphyrin nanoparticles for the treatment of neuroblastoma, Nanotechnology, Science and Applications . 2010, 3: 23-28. |
| Sun R.W.Y. , Li C.K.L. , Ma D.L. , Yan J. , Lok C.N. , Leung C.H. , Zhu N. and Che C.M. , Stable anticancer gold(III)-porphyrin complexes: effects of porphyrin structure, Chemistry - A European Journal . 2010, 16: 3097-3113. |
| Yan J. , Chow L.F. , Leung C.H. , Sun R.W.Y. , Ma D.L. and Che C.M. , Cyclometalated gold(III) complexes with N-heterocyclic carbene ligands as topoisomerase I poisons , Chemical Communications . Britain, Royal Chemical Society, 2010, 46: 3893 - 3895. |
| Researcher : Yan J |
| List of Research Outputs |
| Ho C.M. , Zhang J.L., Zhou C. , Chan O.Y. , Yan J. , Zhang F.Y., Huang J.S. and Che C.M. , A Water-Soluble Ruthenium Glycosylated Porphyrin Catalyst for Carbenoid Transfer Reactions in Aqueous Media with Applications in Bioconjugation Reactions, Journal of the American Chemical Society . 2010, 132: 1886-1894. |
| Lee P.Y. , Zhu Y. , Yan J. , Sun R.W.Y. , Hao W. , Liu X.L., Che C.M. and Wong K.K.Y. , The cytotoxic effects of lipidic formulated gold-porphy rin nanoparticles for the treatment of neuroblastoma, Nanotechnology, Science and Applications . 2010, 3: 23-28. |
| Sun R.W.Y. , Li C.K.L. , Ma D.L. , Yan J. , Lok C.N. , Leung C.H. , Zhu N. and Che C.M. , Stable anticancer gold(III)-porphyrin complexes: effects of porphyrin structure, Chemistry - A European Journal . 2010, 16: 3097-3113. |
| Yan J. , Chow L.F. , Leung C.H. , Sun R.W.Y. , Ma D.L. and Che C.M. , Cyclometalated gold(III) complexes with N-heterocyclic carbene ligands as topoisomerase I poisons , Chemical Communications . Britain, Royal Chemical Society, 2010, 46: 3893 - 3895. |
| Researcher : Yang C |
| List of Research Outputs |
| Chan G.K.Y. , van der Laak N.K. , Li F. , Lam Y.L. , Ting S.W. and Yang C. , Multi-scale Structuring of Composite Electrode Materials for Fuel Cells and Energy Applications, 2nd IWNA International Workshop on Nanotechnology and Application, Vung Tau, Vietnam, November 12-14, 2009 . 2009. |
| Researcher : Yang D |
| Project Title: | Developing aminoxy acids-containing peptide mimics as small moleucle inhibitors of protein-protein interactions |
| Investigator(s): | Yang D |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 08/2006 |
| Completion Date: | 07/2009 |
| Abstract: |
| (1) Design and synthesis of aminoxy acids-containing peptides that form stable helical structures in water (2) design and synthesis of aminoxy acids-based pept ides as α-helix mimics to inhibit protein-protein interactions such as the p53/hDM2 interaction |
| Project Title: | Peptidomimetics: Design, Synthesi s and Biomedical Applications |
| Investigator(s): | Yang D, Xu B, Sun H |
| Department: | Chemistry |
| Source(s) of Funding: | Collaborative Research Fund (CRF) - Group Research Project |
| Start Date: | 02/2007 |
| Completion Date: | 01/2010 |
| Abstract: |
| 1) Design, synthesis, and biological activity of aminoxy acids-based peptides; 2) Using peptidomimetics to understand the transport process of small anions and cations across biological membranes; 3) Developing hydrogels based on aminoxy acids; and 4) Pharmacokinetic studies of selected bioactive peptides containing aminoxy acids |
| Project Title: | Developing Palladium-Catalyzed Asymmetric Tandem Oxidative Cyclization Reactions for Organic Synthesis |
| Investigator(s): | Yang D |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 09/2007 |
| Completion Date: | 08/2009 |
| Abstract: |
| To probe the mechanism of palladium-catalyzed oxidative tandem cyclization reactions; to develop new asymmetric oxidative domino cyclization reactions; to further extend the substrate scope to the synthesis of complex carbocyclic and heterocyclic scaffolds. |
| Project Title: | Palladium-Catalyzed Asymmetric Oxidative Cyclization Reactions and Their Applications in the Synthesis of Alkaloids |
| Investigator(s): | Yang D |
| Department: | Chemistry |
| Source(s) of Funding: | General Research Fund (GRF) |
| Start Date: | 10/2009 |
| Abstract: |
| 1) explore enantioselective cascade cyclization of aliphatic amides; 2) synthesize tricyclic systems through the cyclization of precursors containing mono-c yclic olefins; 3) develop a new synthetic route for synthesis of mitomycin C |
| List of Research Outputs |
| Chan Y.C. , Lee Y.K. , Ng K.M. , Lai K.W.H. , Yang D. , Tse H.F. and Siu D.C.W. , A Newly-derived Small Synthetic Compound Alleviated Ventricular Fibrillation In A Pig Model With Chronic Myocardial Infarction As Revealed By Optical Mapping, Fifth International Symposium on Healthy Aging: “Is Aging a Disease?” (Hong Kong) . 2010. |
| Chang X.W., Zhang D.W., Chen F. , Dong Z.M. and Yang D. , A Concise Asymmetric Route to Chiral a -Aminoxy Acids, Synlett . 2009, 3159-3162. |
| He W. , Yip P.K.T. , Zhu N. and Yang D. , Pd(II)/ t Bu Quinolineoxazoline: An Air-stable And Modular Chiral Catalyst System For Enantioselective Oxidative Cascade Cyclization, Organic Letters . 2009, 11: 5626-5628. |
| Kao P.Y.P. , Yang D. , Lau L.S. , Tsui H.W., Hu L. , Dai J. , Chan M.P. , Chan C.M. , Wang P. , Zheng B. , Sun J. , Huang J. , Madar J., Chen G. , Chen H. , Guan Y. and Yuen K.Y. , Identification of Influenza a Nucleoprotein as an Antivir al Target, Nature Biotechnology . 2010, 28: 600-608. |
| Lee O.Y. , Law K.L. and Yang D. , Secondary Amine Formation from Reductive Amination of Carbonyl Compounds Promoted by Lewis Acid Using the InCl 3 /Et 3 SiH System, Organic Letters . 2009, 11: 3302-3305. |
| Li X. , Shen B., Yao X.Q., Zhu N. and Yang D. , Self-assembled Synthetic Chloride Channels, The 13th Asian Chemical Congress, Shanghai, China, September 1. 2009 . |
| Li X. , Shen B., Yao X.Q. and Yang D. , Synthetic Chloride Channel Regulates Cell Membrane Potentials and Voltage-Gated Calcium Channels, Journal of the American Chemical Society . 2009, 131: 13676-13680. |
| Li X. , Shen B., Yao X.Q., Zhu N. and Yang D. , Synthetic Chloride Channels, The 25th Naito Conference on “Chemical Biology II” , Hokkaido, Japan, September 1, 2009 . |
| Liu X. , Li C.Y. and Yang D. , Total Synthesis of Fumagillol, The 239th American Chemical Society National Meeting, San Francisco, U.S.A., March 1, 2010 . |
| Ma C.H. , Lin H. , Chung I.S. , Yang D. , Liang R.H.S. and Leung A.Y.H. , Distinctive functions of methionine aminopeptidase II in embryonic hematopoiesis in zebrafish embryos., 15th Medical Research Conference . Hong Kong, 2010. |
| Peng T. and Yang D. , Construction of a Library of Rhodol Fluorophores for Developing New Fluorescent Probes, Organic Letters . 2010, 12: 496-499. |
| Xing D. and Yang D. , Gold(I)-Catalyzed Highly Regio- and Stereoselective Decarboxylative Amination of Allylic N-Tosylcarbamates via Base-Induced Aza-Claisen Rearrangement in Water, Organic Letters . 2010, 12: 1068-1071. |
| Xing D. and Yang D. , Gold(I)-Catalyzed Highly Regio- and Stereoselective Decarboxylative Amination of Allylic N-Tosylcarbamates, The 239th American Chemical Society National Meeting, San Francisco, U.S.A., March 1, 2010 . |
| Yang D. , Associate Editor (from Year 2010 upto present), Organic Letters . 2010. |
| Yang D. , Liu G.J., Hao Y. , Li W. , Dong Z. , Zhang D.W. and Zhu N. , Conformational Studies on Peptides of a -Aminoxy Acids with Functionalized Side-Chains, Chemistry - An Asian Journal . 2010, 5: 1356-1363. |
| Yang D. , Construction of Carbocycles and Heterocycles via Atom and Group Transfer Radical Cyclization, The 4th Pacific Symposium on Radical Chemistry, Shanghai, China; November 1, 2009 . 2009. |
| Yang D. , Invited Lecture at Novartis Institute for Biomedical Research, Emeryville, U.S.A.; October 2. 2009 . 2009. |
| Yang D. , Invited lecture at Hong Kong University of Science and Technology,Hong Kong; October 1, 2009 . 2009. |
| Yang D. , Invited lecture at Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China; Decembe r 1, 2009 . 2009. |
| Yang D. , Invited lecture at University of California at Davis, Davis, U.S.A.;October 3, 2009 . 2009. |
| Yang D. , Invited lecture at Yunnan University, Kunming, China, December 1, 2010 . 2009. |
| Yang D. , Invited lecture at the 13th Asian Chemical ongress,Shanghai, China, September 1, 2009 . 2009. |
| Yang D. , Invited lecture at the 25th Naito Conference on “Chemical Biology II” , Hokkaido, Japan; September 1, 2009 . 2009. |
| Yang D. , Invited lecture at the 4th Pacific Symposium on Radical Chemistry, Shanghai, China, November 1. 2009 . 2009. |
| Yang D. , Invited lecture at the 6th Asian-European Symposium on Metal Mediated Efficient Reactions, Singapore, June.1, 2010 . 2010. |
| Yang D. , Invited lecture at the PKU-UCSD Forum on Translational Medicine, Shenzhen, China, January 1, 2010 . 2010. |
| Yang D. , Member of Editorial Advisory Board (from Year 2005 upto present), Beilstein Journal of Organic Chemistry . 2010. |
| Yang D. , Member of Editorial Advisory Board (from Year 2007 upto present), Accounts of Chemical Research . 2010. |
| Yang D. , Member of Editorial Advisory Board (from Year 2010 upto present), The Journal of Organic Letters . 2010. |
| Yang D. , Member of International Advisory Board (from Year 2009 upto present), Chemistry - An Asian Journal . 2010. |
| Yang D. , Plenary Lecture at the 24th W. S. Johnson Symposium in Stanford University, Stanford, U.S.A.;October 1, 2009 . 2009. |
| Yang D. , Plenary lecture at the 11th Tetrahedron Symposium, Beijing, China, June 1. 2010 . 2010. |
| Yang D. , Plenary lecture at the 45th Bürgenstock Conference (EUCHEM Conference on Stereochemistry), Brunnen, Switzerlan d, May 1, 2010 . 2010. |
| Yang D. , Plenary lecture at the 6th National Symposium on Chemical Biology, Xiamen, China; October 1 2009 . 2009. |
| Yang D. , Self-Assembled Synthetic Ion Channels, The 45th Bürgenstock Conference (EUCHEM Conference on Stereochemistry), Brunnen, Switzerland, May 1, 201 0 . 2010. |
| Yang D. , Yip P.K.T. , Yang M., He W. , Chen H. , Song K. and Lo K.Y. , Stereoselective Cyclization Reactions through Palladium and Silver Catalysis, The 6th Asian-European Symposium on Metal Mediated Efficient Reactions, Singapore, June 1, 2010 . 2010. |
| Yang D. , Lian G.Y., Yang H.F., Yu J.D., Zhang D. and Gao X., Synthesis of g -Butyrolactams by Photoinduced PhSe Group Transfer Radical Cyclization and Formal Synthesis of ( ± )-Isocynometrine, Journal of Organometallic Chemistry . 2009, 74: 8610-8615. |
| Yang D. , Sun Z. , Peng T. , Wang L.H., Shen J. , Chen Y. and Tam P.K.H. , Synthetic fluorescent probes for imaging of peroxynitrite and hypochlorous acid in living cells, Methods Mol Biol. . 2010, 591: 93-103. |
| Yang D. , Sun Z. , Peng T. , Wang H.L., Shen J.G., Chen Y. and Tam P.K.H. , Synthetic fluorescent probes for imaging of peroxynitrite and hypochlorous acid in living cells, Methods in Molecular Biology . 2010, 591: 93-103. |
| Yang D. , Using Synthetic Organic Chemistry to Probe Biological Mechanisms,, The 24th W. S. Johnson Symposium in Stanford University, Stanford, U.S.A., October 1, 2009 . |
| Yang D. , Using Synthetic Organic Chemistry to Probe Biological Mechanisms, The 11th Tetrahedron Symposium, Beijing, China, June 1, 2010 . |
| Yang D. , Using Synthetic Organic Chemistry to Probe Biological Mechanisms, The 6th National Symposium on Chemical Biology, Xiamen, China, October 1, 2009 . 2009. |
| Yang D. , Using Synthetic Organic Chemistry to Probe Biological Mechanisms, The PKU-UCSD Forum on Translational Medicine, Shenzhen, China, January 1, 2010 . |
| Zhang Y.H., Song K. , Zhu N. and Yang D. , The Effect of Backbone Stereochemistry on the Folding of Acyclic b 2,3 -Aminoxy Peptides, Chemistry - A European Journal . 2010, 16: 577-587. |
| Researcher : Yang F |
| List of Research Outputs |
| Chan D.S.H. , Lee H.M. , Yang F. , Che C.M. , Wong C.C., Abagyan R., Leung C.H. and Ma D.L. , Structure-Based Discovery of Natural-Product-like TNF-alpha Inhibitors, Angewandte Chemie International Edition . 2010, 49: 2860-2864. |
| Chan D.S.H. , Lee H.M. , Yang F. , Che C.M. , Wong C.C.L., Abagyan R., Leung C.H. and Ma D.L. , Structure-Based Discovery of Natural-Product-like TNF- a Inhibitors, Angewandte Chemie International Edition . 2010, 49: 2860-2864. |
| Lee H.M. , Chan D.S.H. , Yang F. , Lam H.Y., Yan S.C., Che C.M. , Ma D.L. and Leung C.H. , Identification of natural product Fonsecin B as a stab ilizing ligand of c-myc G-quadruplex DNA by high-throughput virtual screening, Chemical Communications . 2010, 46: 4680-4682. |
| Researcher : Yang P |
| List of Research Outputs |
| Cheung K.C. , Yang P. , Huang Q.H., Chen Z., Chen S.J., Lin M.C. and Kung H.F., Identification of Protein Domains Required for Makorin-2-mediated Neurogenesis Inhibition in Xenopus Embryos, Biochemical and Biophysical Research Communications . 2010, 394(1): 18-23. |
| Researcher : Yang Y |
| List of Research Outputs |
| Hui S.K. , Tse M.K. , Yang Y. and Sze K.H. , Backbone and Side-chain 1 H, 13 C and 15 N Assignments of the Ubiquitin-associated Domain of Human X-linked Inhibitor of Apoptosis Prote in , Biomol. NMR Assignments . 2010, 4: 13-15. |
| Liang H.C., Li X.Z., Yang Y. and Sze K.H. , Comparison Of The Degradations Of Diphenamid By Homogeneous Photolysis And Heterogeneous Photocatalysis In Aqueous Solution, Chemosphere . 2010, 80: 366-374. |
| Yang Y. , Mak A.N.S., Shaw P.C. and Sze K.H. , Solution Structure of an Active Mutant of Maize Ribosome-Inac tivating Protein (MOD) and Its Interaction with the Ribosomal Stalk Protein P2, Journal of Molecular Biology . 2010, 395: 897-907. |
| Researcher : Yang Y |
| List of Research Outputs |
| Hui S.K. , Tse M.K. , Yang Y. and Sze K.H. , Backbone and Side-chain 1 H, 13 C and 15 N Assignments of the Ubiquitin-associated Domain of Human X-linked Inhibitor of Apoptosis Protein , Biomol. NMR Assignments . 2010, 4: 13-15. |
| Liang H.C., Li X.Z., Yang Y. and Sze K.H. , Comparison Of The Degradations Of Diphenamid By Homogeneous Photolysis And Heterogeneous Photocatalysis In Aqueous Solution, Chemosphere . 2010, 80: 366-374. |
| Yang Y. , Mak A.N.S., Shaw P.C. and Sze K.H. , Solution Structure of an Active Mutant of Maize Ribosome-Inacti vating Protein (MOD) and Its Interaction with the Ribosomal Stalk Protein P2, Journal of Molecular Biology . 2010, 395: 897-907. |
| Researcher : Yao H |
| List of Research Outputs |
| Yao H. , Ng S.M. , Li M. and Lin M.C. , An Effective Interleukin-2 Cancer Immunotherapy Delivered by a Novel Polymeric nanoparticle in Melanoma, Annual Meeting of the International Society for Biological Therapy of Cancer; 28-31 October, 2009; Washington, USA . 2009. |
| Yao H. , Ng S.M. , Tang G. , Kung H.F. and Lin M.C. , Development of a Low-toxicity and High-efficiency Polyme ric Nanoparticle for Gene Delivery, 2009 International Society for Cell & Gene Therapy of Cancer; Cork, Ireland; 2-4 September, 2009. . 2009. |
| Yao H. , Ng S.M. , Tucker W.O. , Tsang Y.K.T. , Man K. , Wang X.M., Chow B.K.C. , Kung H.F., Tang G. and Lin M.C. , The gene transfection efficiency of a folate-PEI600- cyclodextrin nanopolymer, Biomaterials . 2009, 30(29): 5793-5803. |
| Researcher : Yau KW |
| List of Research Outputs |
| Ho C.M. , Yau K.W. , Lok C.N. , So M.H. and Che C.M. , Oxidative Dissolution of Silver Nanoparticles by Biologically Relevant Oxidants. A kinetic and Mechanistic Study, 17th Symposium of Chemistry Postgraduate Research in Hong Kong . 2010. |
| Ho C.M. , Yau K.W. , Lok C.N. , So M.H. and Che C.M. , Oxidative Dissolution of Silver Nanoparticles by Biologically Relevant Oxidants: A Kinetic and Mechanistic Study, Chemistry - An Asian Journal . 2010, 5: 285-293. |
| Researcher : Yip PKT |
| List of Research Outputs |
| He W. , Yip P.K.T. , Zhu N. and Yang D. , Pd(II)/ t Bu Quinolineoxazoline: An Air-stable And Modular Chiral Catalyst System For Enantioselective Oxidative Cascade Cyclization, Organic Letters . 2009, 11: 5626-5628. |
| Yang D. , Yip P.K.T. , Yang M., He W. , Chen H. , Song K. and Lo K.Y. , Stereoselective Cyclization Reactions through Palladium and Silver Catalysis, The 6th Asian-European Symposium on Metal Mediated Efficient Reactions, Singapore, June 1, 2010 . 2010. |
| Researcher : Yu F |
| List of Research Outputs |
| Li M. , Wang J. , Ng S.M. , Chan C.Y., He M.L., Yu F. , Lai L., Shi C. , Chen Y.C., Yew D.T., Kung H.F. and Lin M.C. , Adenosine Diphosphate-ribosylation Factor 6 is Required for Epidermal Growth Factor-induced Glioblastoma Cell Proliferation, Cancer . 2009, 115(21): 4959-4972. |
| Lin M.C. , Yu F. , Ng S.M. and Kung H.F., Knocking Down Interferon Induced Transmembrane Prote in 1 (IFITM1) Inhibited Cell Proliferation and Invasion in Glioma Cells, Experimental Biology 2010; April 24-28, 2010; Anahei m, California, USA . 2010. |
| Yu F. , Ng S.M. , Lum C.T. , Cheung K.C. , An X.M. and Lin M.C. , Functional Characterization of Interferon Induced Transmembrane Protein 1 (IFITM1) in Colorectal Carcinogenesis, 34th FEBS Congress: Life's Molecular Interactions; Prague, Czech Republic, 4-9, July, 2009. (P4-140, Publis hed in the FEBS Journal) . 2009, 276 (s1): 134. |
| Researcher : Yu SC |
| Project Title: | Functionalized organic semiconductors for organic thin film transistor (OTFT) development |
| Investigator(s): | Yu SC, Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 09/2005 |
| Abstract: |
| The underlying theme of this project is to devel op low-cost and practical organic semiconductors for organic thin film transistor (OTFT) applications. The principal objectives are: 1) to design stable and high performance organic semiconductors for use in OTFT technologies; 2) to develop a temperature-controlled OTFT fabricatio n system for improving device performance; 3) to study the structural effect of organic semiconductors on device performance. Importantly, the overall target is to transfer the technologies developed by this project to other material research programs under investigation at HKU, such as studies on new organic materials for molecular electronics. |
| Researcher : Yu WY |
| List of Research Outputs |
| Li W., Xie Y. , Sun R.W.Y. , Liu Q., Young J., Yu W.Y. , Che C.M. , Tam P.K.H. and Ren Y. , Inhibition of Akt sensitises neuroblastoma cells to gold(III) porphyrin 1a, a novel antitumour drug induced apoptosis and growth inhibition, British Journal of Cancer . 2009, 101(2): 342-349. |
| Researcher : Yuen MY |
| List of Research Outputs |
| Yuen M.Y. , Semiconducting and Electroluminescent Cyclometalated Platinum(II) Complexes: From Molecular Functional Materia ls to Supramolecular Architecture and Self-assembled Nanomaterials (PhD Thesis) . 2010. |
| Researcher : Yuen WH |
| List of Research Outputs |
| Chao J. , Lau K.W. , Huie M.J. , Ho Y.S. , Yu M.S. , Lai S.W. , Wang M. , Yuen W.H. , Lam W.H., Chan T.H. and Chang R.C.C. , A pro-drug of the green tea polyphenol (-)-epigallocatechin-3-gallat e (EGCG) prevents differentiated SH-SY5Y cells from toxicity induced by 6-hydroxydopamine, Neuroscience Letters . 2010, 469: 360-364. |
| Ho Y.S. , Yu M.S. , Yang X. , So K.F. , Yuen W.H. and Chang R.C.C. , Neuroprotective effects of polysaccharides from wolfberry, the fruits of Lycium barbarum . against homocysteine-induced toxicity in rat cortical neurons, Journal of Alzheimer's Disease . 2010, 19: 813-827. |
| Ho Y.S. , Yu M.S. , Yik S.Y. , So K.F. , Yuen W.H. and Chang R.C.C. , Polysaccharides from wolfberry antagonizes glutamate excitotoxicity in rat cortical neurons, Cellular and Molecular Neurobiology . 2009, 29: 1233-1244. |
| Researcher : Yung KF |
| List of Research Outputs |
| Lim B.L. , Leung Y.C. , Yung K.F. , Leung M.K.H. , Mah D.N.Y. , Lam J.C.K. and Hills P.R. , Conference Presentation: "Development of Biofuel Technolo gies and Policy", at the Initiative on Clean Energy and Environment’s Review Workshop, Shenzhen, January 8, 2010 . |
| Researcher : Zeng Y |
| List of Research Outputs |
| Zeng Y. , Biophysical Characteriazation of HPN-LIKE (HPNL), A Histidine- and Glutamine-rich Protein (PhD Thesis) . 2009. |
| Researcher : Zhang D |
| List of Research Outputs |
| Yang D. , Lian G.Y., Yang H.F., Yu J.D., Zhang D. and Gao X., Synthesis of g -Butyrolactams by Photoinduced PhSe Group Transfer Radical Cyclization and Formal Synthesis of ( ± )-Isocynometrine, Journal of Organometallic Chemistry . 2009, 74: 8610-8615. |
| Researcher : Zhang J |
| List of Research Outputs |
| Sun R.W.Y. , Ng F.Y. , Wong E.L.M. , Zhang J. , Chui S.Y. , Shek L. , Lau T.C. and Che C.M. , Dual anti-angiogenic and cytotoxic properties of ruthenium(III) complexes containing pyrazolato and/or pyrazole ligands , Dalton Transactions . 2009, 10712-10716. |
| Researcher : Zhang Q |
| List of Research Outputs |
| Zhang Q. , Chan G.K.Y. and Quirke N., Molecular Dynamics Simulation of Water Confined in a Nanopore of Amorphous Silica, Molecular Simulation . 2009, 35: 1215-1223. |
| Researcher : Zhang Y |
| List of Research Outputs |
| Li X. , Lam H.Y. , Zhang Y. and Chan C.K. , Salicylaldehyde Ester-Induced Chemoselective Peptide Ligations: Enabling Generation of Natural Peptidic Linkages at the Serine/Threonine Sites, Organic Letters . 2010, 12: 1724-1727. |
| Researcher : Zhao W |
| List of Research Outputs |
| Zhao W. , O W.S. , Fung Y.S. and Cheung M.P.L. , Analysis of mitochondria by capillary electrophoresis: Cardiolipin levels decrease in response to carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone, European Journal of Lipid Science and Technology . 2010, 112: 1058-1066. |
| Zhao W. and Fung Y.S. , Capillary Electrophoresis with LIF Detection for Assessment of Mitochondria Based on teh Cardiolipin Content , Abstract, 25th International Symposium on Microscale Bioseparations (MSB 2010), March 21-25, 2010, Prague, Czech Republic . 2010, P168, pp145-146. |
| Zhao W. and Fung Y.S. , Quantitation of Mitochondrial Event Based on Cardiolipin Content Using Capillary Electrophoresis with Laser Induced Fluorescence Detection, Abstract of the 9th Asia-Pacific International Sympo sium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P4-11: pp239. |
| Researcher : Zhao W |
| List of Research Outputs |
| Zhao W. , O W.S. , Fung Y.S. and Cheung M.P.L. , Analysis of mitochondria by capillary electrophoresis: Cardiolipin levels decrease in response to carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone, European Journal of Lipid Science and Technology . 2010, 112: 1058-1066. |
| Zhao W. and Fung Y.S. , Capillary Electrophoresis with LIF Detection for Assessment of Mitochondria Based on teh Cardiolipin Content , Abstract, 25th International Symposium on Microscale Bioseparations (MSB 2010), March 21-25, 2010, Prague, Czech Republic . 2010, P168, pp145-146. |
| Zhao W. and Fung Y.S. , Quantitation of Mitochondrial Event Based on Cardiolipin Content Using Capillary Electrophoresis with Laser Induced Fluorescence Detection, Abstract of the 9th Asia-Pacific International Sympo sium on Microscale Separation and Analysis (APCE 2009) and 1st Asian-Pacific International Symposium on Lab-on-Chip (APLOC2009), October 28-31, 2009, Shanghai, China . 2009, P4-11: pp239. |
| Researcher : Zheng J |
| List of Research Outputs |
| Zheng J. , Zheng X. , Yam C.Y. and Chen G. , Computer Simulation of Feynman’s Ratchet and Pawl System , Physical Review E . 2010, 81: 061104-1 to 061104-15. |
| Zheng J. , Computer Simulation of Maxwell Demon and Feynman's Ratchet and Pawl System (PhD Thesis) . 2009. |
| Zhu D. , Zheng J. and Fung Y.S. , Applicability Study of LiTFSI-Based Room Temperature Ionic Liquids For High Energy Secondary Lithium Ion Battery, Abstract of the 4th Asian Confewrence on Electroch emical Power Sources (ACEP4), November, Taipei, Taiwan, November 8-12, 2009, . 2009, PB04: pp179. |
| Researcher : Zheng J |
| List of Research Outputs |
| Zheng J. , Zheng X. , Yam C.Y. and Chen G. , Computer Simulation of Feynman’s Ratchet and Pawl Syste m , Physical Review E . 2010, 81: 061104-1 to 061104-15. |
| Zheng J. , Computer Simulation of Maxwell Demon and Feynman's Ratchet and Pawl System (PhD Thesis) . 2009. |
| Zhu D. , Zheng J. and Fung Y.S. , Applicability Study of LiTFSI-Based Room Temperature Ionic Liquids For High Energy Secondary Lithium Ion Battery, Abstract of the 4th Asian Confewrence on Electrochemical Power Sources (ACEP4), November, Taipei, Taiwan, Novem ber 8-12, 2009, . 2009, PB04: pp179. |
| Researcher : Zheng J |
| List of Research Outputs |
| Zheng J. , Zheng X. , Yam C.Y. and Chen G. , Computer Simulation of Feynman’s Ratchet and Pawl System , Physical Review E . 2010, 81: 061104-1 to 061104-15. |
| Zheng J. , Computer Simulation of Maxwell Demon and Feynman's Ratchet and Pawl System (PhD Thesis) . 2009. |
| Zhu D. , Zheng J. and Fung Y.S. , Applicability Study of LiTFSI-Based Room Temperature Ionic Liquids For High Energy Secondary Lithium Ion Battery, Abstract of the 4th Asian Confewrence on Electrochemical Power Sources (ACEP4), November, Taipei, Taiwan, November 8-12, 2009, . 2009, PB04: pp179. |
| Researcher : Zheng X |
| List of Research Outputs |
| Zheng J. , Zheng X. , Yam C.Y. and Chen G. , Computer Simulation of Feynman’s Ratchet and Pawl System , Physical Review E . 2010, 81: 061104-1 to 061104-15. |
| Researcher : Zhi YG |
| List of Research Outputs |
| Lai S.W. , Chan Q.K.W. , Han J. , Zhi Y.G. , Zhu N. and Che C.M. , Cyclometalated Pt(II) Complexes bearing Phosphinated Calix[4]arenes, The Sixth National Conference on Coordination Chemistry, The University of Hong Kong, Hong Kong, P. R. China, 6-9 July . 2009. |
| Researcher : Zhou C |
| Project Title: | Gold-Catalyzed Hydroalkylation of Unactivated Alkenes |
| Investigator(s): | Zhou C, Che CM |
| Department: | Chemistry |
| Source(s) of Funding: | Small Project Funding |
| Start Date: | 12/2009 |
| Abstract: |
| C-C bond formation plays a pivotal role in organic synthesis. The addition of a C-H bond across alkene constitutes a particularly valuable and atom-economic method for C-C bond formation, which does not need prefunctionalization of substrates and generate undesired byproducts. The addition of a carbon nucleophile to activated alkene conjugated to an electron-withdrawing group (Michael reaction) is usually employed in organic synthesis. However, addition of a carbon nucleophile to an unactivated alkene remains a difficult task for chemists, which usually requires high temperature under thermal condition without catalyst. The catalytic additio n of a C-H bond across unactivated alkene by radical initiators and Lewis or Brønsted acid catalysis usually suffer from many limitations including poor functional group compatibility, poor selectivity, limited scope, and extreme air- and moisture-sensitivity. Although Hg(II) salts are often employed in selective hydroalkylation of unactivated alkenes, the resulting C(sp3)-Hg bond through addition of Hg(II) salts to alkenes is usually kinetically stable and requires an extra step to release the organic ligand. Thus, the overall transformation require stoichiometric amount of toxic mercury salts. Recently, it has been reported that palladium and platinum complexes can catalyze intramolecular hydroalkylation of unactivated alkenes with β-diketones and indoles. However, these transformations often suffer from undesired β-hydride elimination products and difficult cleavage of Pt-C bond. In this regard, there is need to search for new catalysts for efficient and selective hydroalkylatio n of unactivated alkenes under mild conditions. It has recently been shown that Au(I) and Au(III) complexes can efficiently catalyze a variety of organic reactions via activation of unsaturated C-C bonds. Gold is an exceedingly mild, relatively carbophilic Lewis acid, which can coordinate and activate unsaturated C-C bonds towards nucleophilic attack. This carbophilic and relativ ely nonoxophilic features render gold-catalyzed transformations good chemoselectivity and good functional group compatibility, which are crucial for application in complex molecul ar environments. As gold salts are highly electrophilic towards unsaturated carbon bond, they can promote organic transformations efficiently at room temperature with reaction times of just minutes to give clean reactions, allowing easy purification. Gold salts are robust transiti on metal catalysts with tolerance of air and moisture, which facilitate their practical utility. In contrast, many transition metal complexes are sensitive to both air and moisture and limit their use in industry. Beyond this practical benefit, Au(I) is redox stabile and is not prone to air oxidation, which prevent it to participate in oxidative addition/reductive elimination process so prevalent in late transition-metal catalysi s. Furthermore, gold-alkyl bond is prone to cleavage by protonolysis, addressing the problem associated with Hg(II)-C and Pt(II)-C bond cleavage. Taking all these advantages together, we envisage that gold complexes would have tremendous potential to be highly efficient catalysts for C-C bond formation through the addition of C-H bond across unactivated alkenes. Indeed, we have reported that Au(I) or Au(III) complexes could efficiently catalyze intermolecular and intramolecular additions of heteroatom or carbon nucleophile to una ctivated alkenes and alkynes to form C-C bond and C-N bond (J. Am. Chem. Soc. 2007, 129, 5828; Angew. Chem. Int. Ed. 2008, 47, 3805; Organic Letters, 2006, 8, 2707; Chemistry-A European Journal, 2008, 14, 8353.). With our previous publication records and promising findings, we aim to (1) develop an efficient, atom-economic and environmentally benign process for gold-catalyzed hydroalkylation of unactivated alkenes, addressing several problems including high temperature required under thermal condition with out catalyst, poor functional group compatibility, poor selectivity, limited scope, and extreme air- and moisture-sensitivity by Lewis or Brønsted acid catalysis, the use of high toxic Hg(II) salts, undesired side-reaction (β-hydride elimination) catalyzed by Pd catalyst and difficulty in cleavage of strong Pt-C bond. (2) explore a variety of carbon nucleophiles for hydroalkylation of unactivated alkenes, expanding the substrate scope and improve utility in organic synthesis. (3) develop new class of gold complexes to efficiently catalyze selective hydroalkylation of unactivated alkenes under mild conditio ns. |
| List of Research Outputs |
| Ho C.M. , Zhang J.L., Zhou C. , Chan O.Y. , Yan J. , Zhang F.Y., Huang J.S. and Che C.M. , A Water-Soluble Ruthenium Glycosylated Porphyrin Catalyst for Carbenoid Transfer Reactions in Aqueous Media with Applications in Bioconjugation Reactions, Journal of the American Chemical Society . 2010, 132: 1886-1894. |
| Liu P. , Zhou C. , Xiang S. and Che C.M. , Highly Efficient Oxidative Carbon-carbon Coupling with SBA-15-support Iron Terpyridine Catalyst, Chemical Communications . 2010, 46: 2739-2741. |
| Lo K.Y. , Zhou C. , Wong M.K. and Che C.M. , Silver(I)-mediated Highly Enantioselective Synthesis of Axially Chiral Allenes Under Thermal and Microwave-assist ed Conditions; The Best Poster Presentation for Organic Chemistry, The 15th Symposium on Chemistry Postgraduate Research in Hong Kong . 2010. |
| Lo K.Y. , Zhou C. , Wong M.K. and Che C.M. , Silver(I)-mediated Highly Enantioselective Synthesis of Axially Chiral Allenes Under Thermal and Microwave-as sisted Conditions, Chemical Communications . 2010, 46: 213-215. |
| Wang M. , Zhou C. , Wong M.K. and Che C.M. , Ruthenium-catalyzed Alkylation of indoles with Tertiary Amines by Oxidation of a sp 3 C-H Bond and Lewis Acid Catalysis, Chemistry - A European Journal . 2010, 16: 5723-5735. |
| Researcher : Zhu D |
| List of Research Outputs |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Development of Molecularly Imprinted Polymer Based Piezoelectric Quartz Crystal Biosensori , Extended Abstract of 12th International Symposium on Electroanalytical Chemistry (12th ISEC), Changchun, China, August 12-15, 2009 . Page 151. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Development of Molecularly Imprinted Polymer based Piezoelectric Quartz Crystal Biosensor, Conference proceeding of the The 12th International Symposium on Electroanalytical Chemistry, August 12-15, 2009, . 2009, 151. |
| Sun H. , Chen Q. , Zhu D. and Fung Y.S. , Nucleic Acid Based Piezoelectric Quartz Crystal Biosensor for Detection of E.coli , Conference Proceeding of The 12th International Symposium on Electroanalytical Chemistry, Changchun, China, August 12-15, 2009 . 20. |
| Zhu D. , Zheng J. and Fung Y.S. , Applicability Study of LiTFSI-Based Room Temperature Ionic Liquids For High Energy Secondary Lithium Ion Battery, Abstract of the 4th Asian Confewrence on Electrochemical Power Sources (ACEP4), November, Taipei, Taiwan, November 8-12, 2009, . 2009, PB04: pp179. |
| Researcher : Zhu N |
| List of Research Outputs |
| Au K.M. , Wong M.C. , Chen Z. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , A Novel Class of Bis-cyclometalated Alkynylgold(III) Complexes – Synthesis, Characterization, Photophysics, Electrochemistry and the First Observation of Electroge nerated Chemiluminescence, The 5th International Conference on Gold Science, Technology and its Applications (organized by World Gold Council), Heidelberg, Germany, July 26–29, 2009 . |
| Au K.M. , Wong M.C. , Zhu N. and Yam V.W.W. , Luminescent Cyclometalated N-Heterocyclic Carbene-Containing Organogold(III) Complexes: Synthesis, Characterization, Electrochemistry, and Photophysical Studies, Journal of the American Chemical Society . 2009, 131: 9076-9085. |
| Au K.M. , Chen Z. , Wong M.C. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , Synthesis, Characterization, Photophysical Studies, Electrochemistry and Electrogenerated Chemiluminescence of Bis-cyclometalated Alkynylgold(III) Complexes and their Applications in Organic Light-Emitting Devices, The 42 nd International Union of Pure and Applied Chemistry (IUPAC) Congress, Glasgow, United Kingdom, August 2-7, 2009 . P701_030. |
| Au K.M. , Chen Z. , Wong M.C. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , Synthesis, Characterization, Photophysical Studies, Electrochemistry and the First Observation of Electrogenerat ed Chemiluminescence of Bis-cyclometalated Alkynylgold(III) Complexes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P217. |
| Chan K.M.C. , Tao C.H. , Tam H.L., Zhu N. , Yam V.W.W. and Cheah K.W., Synthesis, Characterization, Luminescence and Non-linear Optical (NLO) Properties of Oxadiazole- and Truxene-Con taining Platinum(II) Alkynyl Complexes with Donor-Acceptor Functionalities, The 42 nd International Union of Pure and Applied Chemistry (IUPAC) Congress, Glasgow, UK, August 2-7, 2009 . P701_46. |
| Chan K.M.C. , Tao C.H. , Tam H.L., Zhu N. , Yam V.W.W. and Cheah K.W., Synthesis, Characterization, Luminescence and Non-li near Optical Properties of Oxadiazole- and Truxene-containing Platinum(II) Alkynyl Complexes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P213. |
| Che C.M. , Kwok C.C. , Lai S.W. , Rausch A.F., Finkenzeller W.J., Zhu N. and Yersin H., Photophysical Properties and OLED Applications of Pho sphorescent Platinum(II) Schiff Base Complexes, Chemistry--A European Journal . 2010, 16: 233-247. |
| Deng Q.H., Chen J., Huang J.S. , Chui S.Y. , Zhu N. , Li G.Y. and Che C.M. , Trapping Reactive Metal Carbene Complexes by a Bis-Pock et Porphyrin. X-ray Crystal Structures of Ru=CHCO2Et and trans-Ru(CHR)(CO) Species and Highly Selective Carbenoid Transfer Reactions, Chemistry - A European Journal . 2009, 15: 10707-10712. |
| He W. , Yip P.K.T. , Zhu N. and Yang D. , Pd(II)/ t Bu Quinolineoxazoline: An Air-stable And Modula r Chiral Catalyst System For Enantioselective Oxidative Cascade Cyclization, Organic Letters . 2009, 11: 5626-5628. |
| He X. , Lam S.W.H. , Zhu N. and Yam V.W.W. , Design and Synthesis of Calixarene-Based Bis-alkynyl-Bridged Dinuclear Au 1 Isonitrile Complexes as Luminescent Ion Probes by the Modulation of Au···Au Interactions, Chemistry - A European Journal . 2009, 15: 8842-8851. |
| He X. , Zhu N. and Yam V.W.W. , Design and Synthesis of Calixarene-based Bis-alkynyl-bridge d Dinuclear Au(I) Isonitrile Complexes as Luminescent Ion Probes via the Modulation of Au … Au Interactions, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P218. |
| He X. , Cheng C.C. , Zhu N. and Yam V.W.W. , Selective Ion Probe for Mg 2+ Based on Au(I) ... Au(I) Interactions in Tripodal Alkynylgold(I) Complex With Oligoether Pendants, , Chemical Communications . 2009, 4016-4018. |
| He X. , Zhu N. and Yam V.W.W. , Synthesis, Characterization, Structure, and Selective Cu 2+ Sensing Studies of an Alkynylgold(I) Complex Containing the Dipicolylamine Receptor, Organometallics . 2009, 28: 3621-3624. |
| Lai S.W. , Chan Q.K.W. , Han J. , Zhi Y.G. , Zhu N. and Che C.M. , Cyclometalated Pt(II) Complexes bearing Phosphinated Calix[4]arenes, The Sixth National Conference on Coordination Chemistry, The University of Hong Kong, Hong Kong, P. R. China, 6-9 July . 2009. |
| Lam S.T. , Zhu N. and Yam V.W.W. , Synthesis and Characterization of Luminescent Rhenium(I) Tricarbonyl Diimine Complexes with a Triarylboron Moiety and the Study of Their Fluoride Ion-Binding Properties, Inorganic Chemistry . 2009, 48: 9664-9670. |
| Lee K.M. , Cheng C.C. , Zhu N. and Yam V.W.W. , Novel Air-stable Hexanuclear Gold(I) Phosphinidene Complexes Containing Redox-active Ferrocenyl Units, The 5 th International Conference on Gold Science, Technology and its Applications (organized by World Gold Council),Heidelberg, Germany, July 26–29, 2009 . |
| Li X. , Shen B., Yao X.Q., Zhu N. and Yang D. , Self-assembled Synthetic Chloride Channels, The 13th Asian Chemical Congress, Shanghai, China, September 1. 2009 . |
| Li X. , Shen B., Yao X.Q., Zhu N. and Yang D. , Synthetic Chloride Channels, The 25th Naito Conference on “Chemical Biology II” , Hokkaido, Japan, September 1, 2009 . |
| Sun R.W.Y. , Li C.K.L. , Ma D.L. , Yan J. , Lok C.N. , Leung C.H. , Zhu N. and Che C.M. , Stable anticancer gold(III)-porphyrin complexes: effects of porphyrin structure, Chemistry - A European Journal . 2010, 16: 3097-3113. |
| Tam A.Y.Y. , Wong M.C. , Zhu N. , Wang G. and Yam V.W.W. , Luminescent Alkynylplatinum(II) Terpyridyl Metalloge ls Stabilized by Pt∙∙∙Pt, p - p , and Hydrophobic-Hydophobic Interactions , Langmuir . 2009, 25: 8685-8695. |
| Tam Y.Y. , Wong M.C. , Zhu N. and Yam V.W.W. , Luminescent Metallogel of Alkynylplatinum(II) Terpyridyl Complexes: Interplay of Metal ... Metal, p - p and Hydrophobic-Hydrophobic Interactions on Gel Formation, , The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 . P216. |
| Tao C.H. , Zhu N. and Yam V.W.W. , Synthesis, Characterisation and Luminescence Properties of Carbazole-Containing Platinum(II) and Palladium(II) Alkynyl Complexes (invited article), Journal of Photochemistry and Photobiology A: Chemis try . 2009, 207: 94-101. |
| Tong S.M. , Law Y.C. , Kui C.F. , Zhu N. , Leung K.H., Phillips D.L. and Che C.M. , Ligand-to-Ligand Charge-Transfer Transitions of Platinum(II) Complexes with Arylacetylide Ligands with Different Chain Lengths: Spectroscopic Characterization, Effect of Molecular Conformations, and Density Functional Theory Calculations, Chemistry - A European Journal . 2010, 16: 6540-6554. |
| Tong S.M. , Kui C.F. , Chao H.Y., Zhu N. and Che C.M. , The 3 [ n d s *( n +1)p s } Emissions of Linear Silver(I) and Gold(I) Chains with Bridging Phosphine Ligands, Chemistry - A European Journal . 2009, 2009: 10777-10789. |
| Tsui W.M. , Huang J.S. , Tong S.M. , Kui C.F. , Che C.M. and Zhu N. , Quinoneimido Complexes of a Metalloporphyrin: Isolation, X-ray Crystal Structures, and DFT Calculations, Chemistry - A Asian Journal . 2010, 5: 759-763. |
| Wong H.L. , Ko C.C. , Lam S.W.H. , Zhu N. and Yam V.W.W. , Design and Synthesis of a New Class of Photochromic Diarylethene-Containing Dithieno[3,2-b:2’,3’-d]pyrroles and Their Switchable Luminescence Properties, Chemistry - A European Journal . 2009, 15: 10005-10009. |
| Wong M.C. , Lam S.W.H. , Zhu N. , Zhou Z.Y. and Yam V.W.W. , Luminescent Polynuclear Alkynylplatinum(II) Complexes with p -Coordination of Various Metal Ions, , The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry) Hong Kong, P.R. China, July 6-9, 2009 (Oral presentati on by Dr Keith Man-Chung Wong) . 2009. |
| Wu P. , Ma D.L. , Leung C.H. , Yan S.C., Zhu N. , Abagyan R. and Che C.M. , Stabilization of G-Quadruplex DNA with Platinum(II) Schiff-base Complexes: Luminescent Probe and Down Regulation of c-myc Oncogene Expression., Chemistry - A European Journal . 2009, 15: 13008-13021. |
| Yam V.W.W. , Song H. , Chan T.W. , Zhu N. , Tao C.H. , Wong M.C. and Wu L.X., Synthesis, Characterization, Ion-Binding Properties, and Fluorescence Resonance Energy Transfer Behavior of Rhenium(I) Complexes Containing a Coumarin-Appended 2,2′-Bipyridine, Journal of Physical Chemistry C . 2009, 113: 11674-11682. |
| Yang D. , Liu G.J., Hao Y. , Li W. , Dong Z. , Zhang D.W. and Zhu N. , Conformational Studies on Peptides of a -Aminoxy Acids with Functionalized Side-Chains, Chemistry - An Asian Journal . 2010, 5: 1356-1363. |
| Zhang Y.H., Song K. , Zhu N. and Yang D. , The Effect of Backbone Stereochemistry on the Foldin g of Acyclic b 2,3 -Aminoxy Peptides, Chemistry - A European Journal . 2010, 16: 577-587. |
| Zhao L., Wong M.C. , Li B., Li W., Zhu N. , Wu L.X. and Yam V.W.W. , Luminescent Amphiphilic 2,6-Bis(1-alkylpyrazol-3-yl)pyridyl Platinum(II) Complexes: Synthesis, Characterization, Electrochemical, Photophysical, and Langmuir-Blodgett Film Formation Studies, Chemistry - A European Journal . 2010, 16: 6797-6809. |
| Researcher : Zu Y |
| List of Research Outputs |
| Au K.M. , Wong M.C. , Chen Z. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , A Novel Class of Bis-cyclometalated Alkynylgold(III) Complexes – Synthesis, Characterization, Photophysics, Electrochemistry and the First Observation of Electrog enerated Chemiluminescence, The 5th International Conference on Gold Science, Technology and its Applications (organized by World Gold Council), Heidelberg, Germany, July 26–29, 2009 . |
| Au K.M. , Chen Z. , Wong M.C. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , Synthesis, Characterization, Photophysical Studies, Electrochemistry and Electrogenerated Chemiluminescence of Bis-cyclometalated Alkynylgold(III) Complexes and their Applications in Organic Light-Emitting Devices, The 42 nd International Union of Pure and Applied Chemistry (IUPAC) Congress, Glasgow, United Kingdom, August 2-7, 2009 . P701_030. |
| Au K.M. , Chen Z. , Wong M.C. , Hung L.L. , Zhu N. , Zu Y. and Yam V.W.W. , Synthesis, Characterization, Photophysical Studies, Electrochemistry and the First Observation of Electrogen erated Chemiluminescence of Bis-cyclometalated Alkynylgold(III) Complexes, The 6 th National Conference on Coordination Chemistry ( cum International Symposium on Coordination Chemistry ) Hong Kong, P.R. China, July 6-9, 2009 . P217. |
| Researcher : Zuo P |
| List of Research Outputs |
| Ma C. , Kwok W.M. , Chan W.S. , Du Y. , Zuo P. , Kan T.W. , Toy P.H. and Phillips D.L. , Time-Resolved Spectroscopy Studies of the Photodeprotection Reactions of p -Hydroxyphenacyl Ester Phototrigger Compounds, Current Science . 2009, 97: 202-209. |
| Researcher : van der Laak NK |
| List of Research Outputs |
| Chan G.K.Y. , van der Laak N.K. , Li F. , Lam Y.L. , Ting S.W. and Yang C. , Multi-scale Structuring of Composite Electrode Materials for Fuel Cells and Energy Applications, 2nd IWNA International Workshop on Nanotechnology and Application, Vung Tau, Vietnam, November 12-14, 2009 . 2009. |
| Li F. , van der Laak N.K. , Ting S.W. and Chan G.K.Y. , Varying Carbon Structures Templated From Kit-6 for Optimum Electrochemical Capacitance , Electrochimica Acta . 2010, 55: 2817-2823. |
| Li W. , Bai Y., Liu C., Yang Z.H., Feng X., Lu X.H., van der Laak N.K. and Chan G.K.Y. , Highly Thermal Stable and Highly Crystalline Anatase TiO 2 for Photocatalysis, Environmental Science Technology . 2009, 43: 5423-5428. |
| Ting S.W. , Cheng S. , Tsang K.Y. , van der Laak N.K. and Chan G.K.Y. , Low Activation Energy Dehydrogenation of Aqueous Form ic acid on Platinum–ruthenium–bismuth Oxide at Near Ambient Temperature and Pressurew, Chemical Communications . 2009, 47: 7333-7335. |