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SOLUTION PROPERTIES OF ANTITUMOR CARBOXYMETHYLATED DERIVATIVES OF α-(1→3)-D-GLUCAN FROM GANODERMA LUCIDUM

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Chinese Journal of Polymer Science 2001年第3期19卷 283-289页

作者： Li-na Zhang Mei Zhang Jing-hua Chen Fan-bo Zeng department of chemistry wuhan university, wuhan 430072, china Pharmacy College, Tongji Medical university, wuhan 430072, china 武汉大学湖北武汉同济医科大学湖北武汉

Fractions of a water insoluble α-(1→3)-D-glucan (GL) extracted from Ganoderma lucidum were carboxy-methylated (CM) to obtain water-soluble carboxymethylated derivatives (CM-GL) having a degree of substitution (DS) of0.38～0.51. Weight-average molecular weight M_w and intrinsic viscosity [η] of the samples CM-GL were measured by gelpermeation chromatography combined with laser light scattering (GPC-LLS) and viscometry. The CM-GL exhibits a stifferchain in aqueous solution at 25℃ than the original glucan, The antitumor activities against Ehrlich ascites carcinoma (EAC,5×10~6) of the carboxymethylated derivatives from the α-glucan and curdlan, a β-glucan, are significantly higher than thoseof the original glucans. The effects of the relatively low molecular weight, expanded chains and better water-solubility of theCM-GL on the enhancement of antitumor activity could not be neglected. The chain stiffness decreased speedily withincrease of temperature from 40 to 60℃ or NaOH concentration from 0.1 to 0.4 in the solution, respectively, and the changeof the chain stiffness is reversible.

关键词： Solution properties Antitumor activity Carboxymethylated derivative α-D-glucan Ganoderma lucidum

Interfacial Interaction Between Polyurethane/Poly(Methacrylateco-Styrene) Coating and the Regenerated Cellulose Film

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wuhan university Journal of Natural Sciences 1998年第1期3卷 92-97页

作者： Gong Ping, Yang Guang, Zhang Lina(department of chemistry, wuhan university, wuhan 430072, china)

Water-resistant films were prepared by coating the surface of regenerated cellulose films with castor oil-based polyurethane (PU)/ poly-(methacrylate-co-styrene) [P (MA-St)]. The effects of the ratio of PU to P (MA-St) copolymer on tensile strength (dry and wet states), vapor permeability, size stability, and water resistivity of the coated films were studied. The interfacial interaction between cellulose and the PU/P (MA-St) coating was analyzed using infrared (IR), ultraviolet (UV), scanning electron microscopy (SEM), transmission electron microscopy (TEM), differential thermal analysis (DTA), and electron probe microanalysis (EPMA). The results indicated that the mechanical properties and water resistivity of the coated films significantly enhanced, and the biodegradability was displayed, when the ratio of PU to P (MA-St) was 8∶2 by weight. The chemical bonds and hydrogen bonds between the cellulose, PU, and the copolymer exist in the coated films. It is regarded that PU/P (MA-St) semi-interpenetrating polymer networks (IPNs) were formed, and a shared network of PU with both the cellulose and the coating in the coated film occurred simultaneously resulting in a strong bonding between the coating layer and the film.

关键词： Key words regenerated cellulose films water resistivity interfacial interaction coating IPNs

SIZE EXCLUSION CHROMATOGRAPHIC COLUMN PACKED WITH REGENERATED CELLULOSE GELS

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Chinese Journal of Polymer Science 2001年第4期19卷 415-419页

作者： Guang Yang Li-na Zhang Xiao-peng Xiong Xiao-dong Cao Yong-liang Yang department of chemistry wuhan university wuhan 430072, china 武汉大学湖北武汉

Microporous regenerated cellulose gel particles were prepared by mixing cellulose cuoxam with silk fibroin as pore former, and the mean pore size and pore volume of the particles were 525 nm and 7.27 mt g(-1), respectively. A preparative size-exclusion chromatography (SEC) column (550 mm x 20 mm) packed with the cellulose gel particles was used for the fractionation of two polysaccharides Dextran 07 (M-W = 7.14 x 10(4), d = 1.7) and Dextran 50 (M-W = 50.5 x 10(4), d = 3.8) in water phase. The fractionation range of the stationary phase covered M, from 3 x 10(3) to 1.1 x 10(6). The daily throughput was 2.9 g for Dextran 07 (D07) and 4.3 g for Dextran 50 (D50) with a flow-rate of 1.5 mt min(-1). The fractions obtained by using the SEC were analyzed by an analytical SEC combined with laser light scattering (LLS), and the polydispersity indices of fractions for Dextran 07 and Dextran 50 were determined to be 1.34-1.57 and 1.53-3.36, respectively. The preparative SEC is a simple, rapid, and suitable means not only for the fractionation of polysaccharides in water but also for other polymers in organic solvents.

关键词： cellulose packing silk fibroin preparative chromatography polysaccharides

POLYMERIZATION OF ETHYLENE METHYL PHOSPHATE IN THE PRESENCE OF SODIUM POLY(ETHYLENE GLYCOL)ATE

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Chinese Journal of Polymer Science 1999年第3期17卷 259-264页

作者： Jie Wen Ren-xi Zhuo Lu Wang Laboratory of Biomedical Materials of the State te Education Commission of china, department of chemistry, wuhan university, wuhan 430072, china 武汉大学化学系生物医用高分子材料开放实验室湖北武汉 430072 武汉大学化学系生物医用高分子材料开放实验室湖北武汉

Poly(ethylene methyl phosphate)-poly(ethylene glycol)-poly(ethylene methyl phosphate) triblock copolymers carrying hydroxyl group at both chain ends were synthesized with sodium poly(ethylene glycol)ate as initiator. The effects of the factors such as solvent, amount of the initiator and reaction time were investigated. The copolymers were characterized by IR, H-1-NMR, H-1{P-31}-NMR, C-13-NMR, P-31{H-1}-NMR, and DSC. High molecular weight of the copolymer and high yield of the polymerization were achieved within 3 min at 25 degrees C. The polymerization process was studied by P-31{H-1}-NMR and transesterification was found during longer polymerization time.

关键词： ethylene methyl phosphate sodium poly(ethylene glycol)ate telechelic polymer block copolymer

Synthesis and Characterization of a Proton-transfer Complex of 1,2,4,5-benzenetetracarboxylic Acid with 1,10-phenanthroline

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Journal of wuhan university of Technology(Materials Science) 2005年第4期20卷 38-42页

作者：孙聚堂 department of chemistry Wuhan University Wuhan 430072 China

A proton-transfer complex of 1,2,4,5-benzenetetracarboxylic acid（H4 BTC）with 1,10-phenanthroline（phen）[（H2BTC）^2-·2（Hphen）^＋·（H4BTC）]was synthesized and characterized by IR,UV-Vis spectra and luminescence. The structure was determined by X-ray single crystal *** crystallizes in the triclinic system,space group P-1 with a=7.3767（15）,b=10.704（2）,c=12.890（3）A.α=102.96（3）,β105.71（3）,γ=99.68（3）°,V=926.0（3）A^3,Dc=1.558g/cm^3,Z=2,μ（Mo-Kα）=0.121mm^-1 and F（000）=*** final R=0.0401 and wR=0.0862 for 2983 observe reflections with[1〉2σ（I）].It is composed of discrete H4 BTC molecules,H2BTC^2- ANIONS AND [Hphen]^＋ *** extensive hydrogen-bonding associations fonned between the H4 BTC molecules and H2BTC^2- anions result in the formation of a two-dimensional layer,to which the [Hphen]^＋ cations are attached through the hydrogen bonds formed between the carboxyl groups of H4 BTC and the NH groups of [Hphen]^＋.Under the excitation of UV *** emits an intense blue luminescence.

关键词： proton-transfer 1,2,4,5-benzenetetracarboxylic acid 1,10-phenanthroline

Organic Solvents Enhanced Spectrofluorimetric Method for Determination of Laccase Activity

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wuhan university Journal of Natural Sciences 1998年第1期3卷 123-125页

作者： Huang Zuyun, Liu Zhihong, Cat Ruxiu, Zeng Yun’e(department of chemistry, wuhan university,wuhan 430072, china) department of chemistry Wuhan University Wuhan China

A novel fluorimetric method for determination of laccase activity in organic solvents is proposed, based on the oxidation ofo-phenylenediamine (1,2-diaminobenzene, OPDA) catalyzed by laccase yielding 2,3-diaminophenazine. The optimal conditions for laccase in organic media areT=55°C, pH=6.5, 1.0×10?2mol/L OPDA, 1.25 mL ethanol, 1.25 mL 1,4-dioxane and 1.25 mL acetone. The linear range of the method proposed in ethanol, 1,4-dioxane and acetone media were 0.44–19.33, 0.11–20.85, 0.38–21.05 U with the detection limit of 0.088, 0.022, 0.076 U, respectively. The proposed method has been applied to the analysis of laccase activity of real samples with more accurate and sensitive than that of the previous method reported.

关键词： Key words Organic solvent laccase activity fluorimetry o phenylenediamine (OPDA)

THERMAL-SENSITIVE BETA-CYCLODEXTRIN-CONTAINING POLY(NISOPROPYLACRYLAMIDE)HYDROGELS CROSSLINKED BY Si—O—Si BONDS—SYNTHESIS,CHARACTERIZATION AND PROLONGING IN VITRO RELEASE OF 5-FLUOROURACIL

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Chinese Journal of Polymer Science 2005年第5期23卷 513-519页

作者： Jian-tao Zhang Shi-wen Huang Ya-nan Xue Ji Liu and Ren-xi Zhuo Key Laboratory of Biomedical Polymers,Ministry of Education department of chemistry,wuhan university,wuhan 430072,china Key Laboratory of Biomedical Polymers Ministry of Education Department of Chemistry Wuhan University Wuhan 430072

A series of novel p（N-isopropylacrylamide）（PNIPAM） hydrogels were synthesized by radical copolymerization of N-isopropylacrylamide （NIPAM） and 3-methacryloxypropyltrimethoxysilane （MPTMS）. The copolymers were then crosslinked through hydrolysis of the siloxane in acetic acid/water mixed solvent. Beta-cyclodextrin （Beta-CD） was introduced into the polymeric networks by condensation of 3-glycidoxypropyltrimethoxysilane derived beta-cyclodextrin （KH560-beta-CD） with MPTMS under acidic condition. These gels were heterogeneous, porous and exhibited fast deswelling kinetics when the temperature was elevated to above lower critical solution temperature （LCST）. The swelling ratios of the gels containing beta-CD at room temperature were higher than that of the normal PNIPAM hydrogel, which was caused by the lower crosslinking density in beta-CD contained gels. In comparison to that of the normal PNIPAM gel, the amount of loaded-drug in the hydrogel containing beta-CD was higher, and the release time of 5-fluorouracil （5-Fu） was prolonged, which was attributed to the formation of inclusion compounds between 5-Fu and beta-CD in gel network.

关键词： Hydrogel Thermal-sensitive Poly(N-isopropylacrylamide) Beta-Cyclodextrin Fast responsive.

Recent progress in polymer-based gene delivery vectors

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Chinese Science Bulletin 2003年第13期48卷 1304-1309页

作者： HUANG Shiwen & ZHUO Renxi department of chemistry, wuhan university, wuhan 430072, china Correspondence should be addressed to Zhuo Renxi (e-mail: pibmp@ ***) department of chemistry Wuhan University Wuhan 430072 China

The gene delivery system is one of the three components of a gene medicine, which is the bottle neck of current gene therapy. Nonviral vectors offer advantages over the viral system of safety, ease of manufacturing, etc. As important nonviral vectors, polymer gene delivery systems have gained increasing attention and have begun to show increasing promising. In this review, the fundamental and recent progress of polymer-based gene delivery vectors is reviewed.

关键词：基因治疗基因转移内吞作用质粒DNA

STUDY ON THE CONCENTRATION DEPENDENCE OF ORIENTATION OF POLYSTYRENE ON SILVER BY THE SERS TECHNIQUE

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Chinese Journal of Polymer Science 2000年第2期18卷 177-180页

作者： Dong-hui Zhang Jin-gui Qin Jing-shu Shen You Wang Wan-jun Liu department of chemistry, wuhan university, wuhan 430072, china Polymer Physics Laboratory, Institute of chemistry, Chinese Academy of Sciences Beijing 100080, china 武汉大学湖北武汉中科院化学所高分子物理及化学国家重点实验室北京

Polystyrene films were adsorbed onto a silver surface from dichloromethane solutions with concentrations of 0.1 to 12 wt%, and then studied by the surface enhanced Raman technique. A critical concentration for coil in... 详细信息

关键词： surface enhanced Raman scattering (SERS) polystyrene concentration dependence