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Norvancomycin-capped silver nanoparticles: Synthesis and antibacterial activities against E. coli

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Science China Chemistry 2007年第3期50卷 418-424页

作者： WEI QingShan JI Jian FU JinHong shen jiacong Department of Polymer Science and Engineering Key Laboratory of Macromolecule Synthesis and Functionalization(Ministry of Education)Zhejiang UniversityHangzhou 310027China

The synthesis of norvancomycin (NVan)-capped silver nanoparticles (Ag@NVan) and their notable in vitro antibacterial activities against E. coli, a Gram-negative bacterial strain (GNB), are reported here. Mercaptoacetic acid-stabilized spherical silver nanoparticles with a diameter of 16±4 nm are prepared by a simple chemical reaction. The formation process of the silver nanoparticles is investigated by UV-visible (UV-vis) spectroscopy and transmission electron microscopy (TEM). NVan is then grafted to the terminal carboxyl of the mercaptoacetic acid in the presence of N-(3-Dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDAC). The TEM images of single bacteria treated with Ag@NVan show that plenty of Ag@NVan aggregate in the cell wall of E. coli. A possible antibacterial mechanism is proposed that silver nanoparticles may help destroy the stability of the outer membrane of E. coli, which makes NVan easier to bind to the nether part of the peptidoglycan structure. The antibacterial activities of silver nanoparticles on their own, together with the rigid polyvalent interaction between Ag@NVan and cell wall, enables Ag@NVan to be an effective inhibitor of GNB. This kind of bionanocomposites might be used as novel bactericidal materials and we also provide an effective synthesis method for preparing functional bioconjugated nanoparticles here.

关键词： silver nanoparticle norvancomycin Gram-negative bacterial strain bioconjugate

Zwitterionic phosphorylcholine-protected water-soluble Ag nanoparticles

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Science China Chemistry 2009年第1期52卷 64-68页

作者： JIN Qiao LIU Xiangsheng XU JianPing JI Jian shen jiacong Key Laboratory of Macromolecule Synthesis and Functionalization of Ministry of Education Department of Polymer ScienceZhejiang UniversityHangzhou 310027China

The water-soluble Ag nanoparticles capped with novel zwitterionic thioalkylated phosphorylcholine were *** Ag nanoparticles showed remarkable stability in saline media with salt concen-trations as high as 2.0 mol/L and plasma using UV-vis absorption ***,compared with tiopronin and citrate-protected Ag nanoparticles,the zwitterionic phosphorylcholine Ag nanopar-ticles did not precipitate out of solution when charged polyelectrolytes or biopolymers were *** zwitterionic phosphorylcholine might be a better ligand for stabilizing metal nanoparticles.

关键词： Ag nanoparticles phosphorylcholine zwitterion biomimetic chemistry

Photoluminescence and Electroluminescence of Poly p-Phenyl Phenol Prepared by Enzymatic Catalyzed Polymerization

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Chinese Physics Letters 1994年第6期11卷 387-389页

作者： MA Yuguang TANG Jianguo MA Lin LIU Shiyong shen jiacong The National Laboratory of Integrated Optic Electronics The National Laboratory of Enzyme Engineering The Key Laboratory for Molecular Spectra and Structure Jilin UniversityChangchun 130023

The photoluminescence(PL)peak of poly p-phenyl phenol(PPP)is at about 370-420nm excited by the light at *** absorption band edges and photon emitting peaks of the polymer are found the conjugated lengths dependent on molecular weight of *** the transient luminescence measurement the lifetime of PL decay is determined to be 2.0ns which is supposed an evidence of polaron excitation *** electroluminescence is observed with aluminum/PPP/indium-tinoxide cell.

关键词： Phenol Polymerization excited

Blue-Green Electroluminescent Diodes Utilizing Tris (8-Quinolinolato)-Aluminum Doped Poly (Vinylcarbazole)

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Chinese Physics Letters 1994年第7期11卷 454-456页

作者： MA Yuguang TANG Jianguo LIU Shiyong ZHANG Ruifeng shen jiacong National Laboratory of Integrated Optic Electronics Key Laboratory of Molecular Spectra and Structure Jilin UniversityChangchun 130023

Blue-green electroluminescent diodes utilizing tris(8-Quinolino1ato)-aluminum doped poly(vinylcarbazole)have been demonstrated.A Schottky-type electroluminescent diode of the polymer film is driven at 20V and has a pe... 详细信息

关键词： Schottky diodes Electroluminescent

Blue Electroluminescent Devices Using the Dye Doped Polymers as Emitter and the Organic Molecule Film as Hole Blocking Layer

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Chinese Physics Letters 1995年第6期12卷 381-384页

作者： MA Yuguang WU Jun XUE Shanhua TIAN Wenjing LIU Shiyong shen jiacong Key Laboratory of Molecular Spectra and Structure Jilin UniversityChangchun 130023 National Laboratory of Integrated Optic Electronics Jilin UniversityChangchun 130023

By placing a hole blocking layer between the polymer and the metallic electrode,we have achieved improved efficiencies for blue electroluminescent devices fabricated with poly(N-vinylcarbazole)doped with 1,1,4,4,-tetraphenyl-1,3-butadiene as the emitter layer and with aluminum and indium/tin-oxide as the electron and hole injecting *** bilayer device yields bright blue emission having intensity of 300cd/m^(2),in same case the devices without hole blocking layer have luminance of only 44 cd/m^(2).

关键词： emitter Electroluminescent layer

Carriers Confinement for Polymer Electroluminescent Devices with Multilayer Structure

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Chinese Physics Letters 1995年第7期12卷 428-430页

作者： MA Yuguang TIAN Wenjing XUE Shanhua HUANG Jinsong LIU Shiyong shen jiacong Key Laboratory of Molecular Spectra and Structure Changdun 130023 National Laboratory of Integrated Optical Electronics Jilin UniversityChangdun 130023

The polymer electroluminescence (EL) device with PBD as carriers confinement layer yields bright blue emission having intensity of 300cd/m^(2),in same case the device without PBD layer have luminance only 44 cd/m^(2).The effect of PBD layer on EL characteristic was *** results show that only in EL devices with PBD thick-ness over 30nm,the holes are completely confined in emitting *** luminance over 2000cd/m^(2) can be obtained by inserting an electron injecting layer between the negative electrode and PED to increase the electron injection.

关键词： layer electrode thick

Conformations and adsorption behavior of poly(allylamine hydrochloride) studied by single molecule force spectroscopy

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Chinese Science Bulletin 2008年第1期53卷 22-26页

作者： YU Ying WANG Fang SHI WeiQing WANG LiYan WANG WenBin shen jiacong Key Lab of Supramolecular Structure and Materials Jilin University Changchun 130012 China

Poly(allylamine hydrochloride) (PAH), which is frequently used in fabricating polyelectrolyte multilayer films, was studied by single molecule force spectroscopy (SMFS). Plenty of force-extension curves with a long plateau were obtained in water, indicating that train-like structure was predominant when PAH was adsorbed on the substrate. It was found that the peak-type force-extension curves of PAH in water were not able to be fitted by the modified freely-jointed chain model. Additionally, there was a flat region in the derivative of force-extension curves. Thus, it was inferred that PAH chain in water was in a special conformation and underwent a "conformational transition" under the stretching of an external force. This phenomenon did not appear in the SMFS experiment in 1 mol/L urea solution, which indi-cated that urea was able to break the special conformation.

关键词：光谱学单分子吸附丙烯胺

Supramolecular science: A new way to understand the matter world

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Chinese Science Bulletin 2003年第15期48卷 1517-1518页

作者： ZHANG Xi & shen jiacong Key Lab for Supramolecular Structure & Materials, College of Chemistry, Jilin University, Changchun 130023, China Key Lab for Supramolecular Structure & Materials College of Chemistry Jilin University Changchun 130023 China

Explores supramolecular science as a new way for understanding the world of matter. Autonomous organization of components in supramolecular chemistry; Nature mimic as the the most significant source for supramolecular research; Construction of functional organized systems; Demand for miniaturization and high-performance properties in microelectronics.

关键词：超分子化学分子识别分子自组装超分子材料

Biosynthesis of selenosubtilisin: A novel way to target selenium into the active site of subtilisin

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Chinese Science Bulletin 2008年第16期53卷 2454-2461页

作者： LI Jing LIU XiaoMan JI YueTong QI ZhenHui GE Yan XU JiaYun LIU JunQiu LUO GuiMin shen jiacong State Key Laboratory of Supramolecular Structure and Materials Jilin University Changchun 130012 China Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education Jilin University Changchun 130023 China

Glutathione peroxidase (GPx, EC1.***.1.9), an important anti-oxidative selenoenzyme, can catalyze the reduction of harmful hydroperoxides with concomitant glutathione, thereby protecting cells and other biological issues against oxidative damage. It captures considerable interest in redesign of its function for either the mechanism study or the pharmacological development as an antioxidant. In order to de- velop a general strategy for specifically targeting and operating selenium in active sites of enzymes, the catalytically essential residue selenocysteine (Sec) was first successfully bioincorporated into the catalytic center of subtilisin by using an auxotrophic expression system. The studies of the catalytic activity and the steady-state kinetics demonstrated that selenosubtilisin is an excellent GPx-like bio- catalyst. In comparison with the chemically modified method, biosynthesis exhibits obvious advan- tages: Sec could be site-directly incorporated into active sites of enzymes to overcome the non-speci- ficity generated by chemical modification. This study provides an important strategy for specifically targeting and operating selenium in the active site of an enzyme.

关键词：生物合成硒非金属元素枯草杆菌蛋白酶