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Development of novel and sensitive sensors based on microcantilever of atomic force microscope

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Progress in Natural Science:Materials International 2006年第5期16卷 445-451页

作者： JIN Yan, WANG Kemin and JIN Rong (State Key Laboratory of Chemo/Biosensing and Chernometrics, Institute of Biological Technology, College of chemistry and chemical {2., hunan university, changsha 410082. china) [a]State Key Laboratory of Chemo Biosensing and Chemometrics Institute of Biological Technology College of Chemistry and Chemical Engineering Human University Changsha China

Recently, the development of sensors based on microfabricated cantilevers of atomic force microscope (AFM) has attracted considerable attention from the designers of novel physical, chemical, and biological sensors. Many kinds of sensors have been developed taking the advantages of its high-resolution imaging, force measurement and force sensitivity, such as immunosensor and DNA biosensor and the sensors for detection of intermolecular interaction. This paper reviews the progress made in this field and discusses the signal transfer principles by which the design of the sensors is achieved.

关键词： atomic force microscopy microcantilever sensor.

Resolution of α-cyclohexyl-mandelic acid enantiomers by two-phase (O/W) recognition chiral extraction

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Science china chemistry 2007年第6期50卷 764-769页

作者： TANG KeWen1,2. ZHANG GuoLi2. HUANG KeLong2. LI Yuanjian3 & YI JianMin1,2.1 Department of chemistry and chemical {2., hunan Institute of Science and Technology, Yueyang 414000, china 2.College of chemistry and chemical {2., Central South university, changsha 410083, china 3 College of Pharmaceutical Science, Central South university, changsha 410078, china Department of chemistry and chemical {2. Hunan Institute of Science and TechnologyYueyang 414000China College of chemistry and chemical {2. Central South UniversityChangsha 410083China

This paper presents a new chiral separation technology:two-phase(O/W)recognition chiral *** behavior of alpha-cyclohexyl-mandelic acid enantiomers was studied in the extraction system with D(L)-isobutyl tartrate in 1,2.dichloroethane organic phase and beta-CD derivatives in aqueous phase,and the influence of the kind and concentration of extractant and pH on extraction performance was *** experimental results indicate that two-phase(O/W)recognition chiral extraction is of strong chiral separation ***-^-CD,HE-beta-CD and Me-beta-CD have higher recognition ability for S-CHMA than that for R-CHMA,among which HP-beta-CD has the strongest ability;whereas,D-isobutyl tartrate has reversed recognition ability for *** the extraction system containing HP-beta-CD and D-isobutyl tartrate,e.e.% of S-CHMA in aqueous phase reached 2..6% by one stage extraction,and the distribution ratio for R-CHMA(k_R)and for S-CHMA(k_S)and separation factor(alpha)are 2.44,0.89 and 2.49,***,pH and concentration of extractant have great effects on chiral separation ***-phase(O/W)recognition chiral extraction has great significance for preparative separation of racemic compounds.

关键词： two-phase(W/0)recognition chiral extraction alpha-cyclohexyl-mandelic acid enantiomers

Silylated and acetylated β-cyclodextrins for gas chromatographic stationary phases

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Journal of Central South university of Technology 2001年第4期8卷 239-243页

作者： TANG Ke wen 1,2.,YI Jian ming 2.ZHOU Chun shan 1,ZHONG Shi an 1 (1. College of chemistry and chemical {2., Central South university, changsha 410083, china 2. College of chemistry and chemical {2., Yueyang Normal university 1. College of chemistry and chemical {2. Central South University 410083 Changsha China 2. College of chemistry and chemical {2. Yueyang Normal University 414000 Yueyang China

Two new chiral stationary phases, 2.3 di O acetyl 6 O trimethylsilyl β cyclodextrin (DATBCD) and 2.6 di O trimethylsilyl 3 O acetyl β cyclodextrin(DTABCD), were synthesized, their structures were identified by means of infrared and NMR spectra. Capillary columns were coated with the two stationary phases by dynamic method. The chromatographic properties, and enantiomers separation, such as ketone, esters, alcohols and olefines, were investigated on the silylated and acetylated β cyclodextrin stationary phases. The experimental results show that the silylated and acetylated β cyclodextrins are suitable to be used as capillary gas chromatographic stationary phases, the relative polarity of DATBCD and DTABCD stationary phases is respectively 4143 and 392., the column efficiencies are respectively 3084 and 4198, and DATBCD is of stronger enantioselectivity than DTABCD, capacity factor of the first eluted enantiomer ( k 1) and separation factor(α)of α phenylethanol on DATBCD stationary phase are respectively 8.2. and 1.019.

关键词： capillary gas chromatography silylated and acetylated β-cyclodextrins enantiomeric separation

Preparation of well-defined polystyrene/silica hybrid nanoparticles by ATRP

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Science china chemistry 2008年第1期51卷 51-57页

作者： OU BaoLi1,2.LI DuXin2.1 College of chemistry and chemical {2.,hunan university of Science and Technology,Xiangtan 4112.1, china 2.State Key Laboratory of Powder Metallurgy,Central South university,changsha 410083, china 1. College of chemistry and chemical {2. Hunan University of Science and Technology Xiangtan 411201 China 2. State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China

Immobilization of the atom transfer radical polymerization (ATRP) macroinitiators at the silica nanoparticle surfaces was achieved through surface modification with excess toluene-2.4-diisocynate (TDI), after which the residual isocyanate groups were converted into ATRP macroinitiators. Structurally well-defined polystyrene chains were grown from the nanoparticle surfaces to yield individual particles composed of a silica core and a well-defined, densely grafted outer polystyrene by ATRP, which was initiated by the as-synthesized silica-based macroinitiator. FTIR, NMR and gel permeation chro-matography (GPC) were used to characterize the polystyrene/silica hybrid particles.

关键词： silica nanoparticles surface modification atom transfer radical polymerization polystyrene hybrid particle

Preparation of polystyrene/silica nanocomposites by radical copolymerization of styrene with silica macromonomer

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Science china chemistry 2007年第3期50卷 385-391页

作者： OU BaoLi1,2.& LI DuXin2.1 College of chemistry and chemical {2., hunan university of Science and Technology, Xiangtan 4112.1, china 2.State Key Laboratory of Powder Metallurgy, Central South university, changsha 410083, china 1. College of chemistry and chemical {2. Hunan University of Science and Technology Xiangtan 411201 China 2. State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China

A two-stage process has been developed to generate the silica-based macromonomer through surface-modification of silica with polymerizable vinyl groups. The silica surfaces were treated with excess 2.4-toluene diisocynate (TDI), after which the residual isocyanate groups were converted into polymerizable vinyl groups by reaction with hydroxypropylacrylate (HPA). Thus, polystyrene/silica nanocomposites were prepared by conventional radical copolymerization of styrene with silica macromonomer. The main effecting factors, such as ratios of styrene to the macromonomer, together with polymerization time on the copolymerization were studied in detail. FTIR, DSC and TGA were utilized to characterize the nanocomposites. Experimental results revealed that the silica nanoparticles act as cross-linking points in the polystytene/silica nanocomposites, and the glass transition temperatures of the nanocomposites are higher than that of the corresponding pure polystyrene. The glass transition temperatures of nanocomposites increased with the increasing of silica contents, which were further ascertained by DSC.

关键词： silica nanoparticles surface modification styrene radical copolymerization nanocomposites

Influence of steric and intramolecular inductive effects on the variable trends in R-X (R=Alkyl) bond dissociation energy

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Science china chemistry 2009年第7期52卷 943-951页

作者： CAO ChenZhong School of chemistry and chemical {2., hunan university of Science and Technology, Xiangtan 4112.1, china School of chemistry and chemical {2. Hunan University of Science and Technology Xiangtan 411201 China

The question "why are the variation trends of R-X bond dissociation energy different?" is answered. The R-X bond dissociation energy (BDE) may be influenced by three main factors: the C-X intrinsic bond energy, the 1,3 geminal repulsion, and the intramolecular charge-induced dipole. In the presence of atom X, the variation trend of BDE in R-X (R= Me, Et, i-Pr, t-Bu) is dominated by two factors, the 1,3 geminal repulsion and the intramolecular charge-induced dipole. The former decreases the R-X BDE, and the latter either increases or decreases the R-X BDE. For the series of R-X with the R-C bond (such as R-Me, R-CH == CH2. R-C≡CH, and R-CN), the 1,3 geminal repulsion decreases the R-X BDE, and the variation trends of R-C BDE decrease from Me to t-Bu. As regards the series of R-X (such as R-H, R-BH2. and R-SiH2. in which the electronegativity of atom X is smaller than that of the carbon atom, the above two factors decrease the R-X BDE, and the variation trends of the R-X BDE decrease from Me to t-Bu. As to the series of R-X (such as R-F, R-OH, R-Cl, R-Br, R-I, and R-NH2. in which the electronegativity of atom X is larger than that of the carbon atom, the 1,3 geminal repulsion decreases the R-X BDE, while the intramolecular charge-induced dipole increases the R-X BDE. In this case, the variation trends of R-X BDE depend on the competition of the two factors. As a result, some of them (e. g., R-F, R-OH) increase from Me to t-Bu, some (e. g., R-I) decrease from Me to t-Bu, and some (e. g., R-Br) change very little.

关键词： bond dissociation energy charge-induced dipole geminal repulsion ionic configuration

Ion Selective Electrode Array Analysis Using Variable Step-Size Generalized Simulated Annealing

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chemical Research in Chinese Universities 1993年第4期9卷 296-302页

作者： WANG Shi-hua, XIAO Dan and YU Ru-qin (Department of chemistry and chemical {2.,hunan Univ. ,changsha,410082.

A global optimum location algorithm called Variable Step-Size Generalized Simulated Annealing(VSGSA) was applied to treating the data obtained by using an array of ion-electrodes in solutions containing mixtures of Na+, K+, Ca2.. Unlike traditional optimization algorithms such as simplex procedure, VSGSA can be used to determine the model parameters without any priori information about the analytical system under investigation and overcome the disadvantage of simplex method which might converge to local extrema depending on the starting positions. The algorithm was applied to po-tentiometric determination of ions in mixture solutions.

关键词： Chemometrics Multivariate calibration Array of ion-selective electrodes,Generalized simulated annealing

Aspects of recent developments in analytical chemometrics

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Science china chemistry 2006年第3期49卷 193-203页

作者： LIANG Yizeng1,2. WU Hailong1, SHEN Guoli1, JIANG Jianhui1, LIANG Sheng2.& YU Ruqin1 1. State Key Laboratory of Chemo/Biosensing and Chemometrics, College of chemistry and chemical {2., hunan university, changsha 410082. china 2. Research Center of Modernization of Traditional Chinese Medicines, Central South university, changsha 410081, china 1. State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha 410082 China 2. Research Center of Modernization of Traditional Chinese Medicines Central South University Changsha 410081 China

Some aspects of recent developments in analytical chemometrics are discussed, in par- ticular the developments viewed from the angle of the research efforts undertaken in authors’ labora- tories. The topics concerned include resolution of high-order chemical data, morphological theory and methodology for chemical signal processing, multivariate calibration and chemical pattern recognition for solving complex chemical problems, and resolution of two-way chemical data from hyphenated chromatographic instruments.

关键词： chemometrics, high-order chemical data, pattern recognition, multivariate calibration and resolution.

Quantitative detection of ING1 mRNA under different gene regulation based on molecular beacon

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Chinese Science Bulletin 2006年第17期51卷 2059-2064页

作者： LIU Bin1,2.3,4, WANG Kemin1,2.3,4, XIAO Zhiqiang5,6, WANG Wei1,3,4, TAN Weihong1,2.3,4, SUN Yi5,6, TANG Hongxing1,3,4 & YANG Xiaohai1,3,41. State Key Laboratory of Chemo/Biosensing and Chemometrics, Hu- nan university, changsha 410082. china 2. Life Science and Biotechnology Institute,{2., Chang- sha 410082. china 3. chemistry and chemical Engineer College,{2., changsha 410082. china 4. hunan engineering Research Center for Bio-Nanotechnology,{2., changsha 410082. china 5. Medical Experiment Research Center, Xiangya Hospital, Central South university, changsha 410008, china 6. Key Laboratory of Cancer Proteomics of Chinese Ministry of Health, changsha 410008, china State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan University Changsha China Life Science and Biotechnology Institute Hunan University Changsha China chemistry and chemical Engineer College Hunan University Changsha China hunan engineering Research Center for Bio-Nanotechnology Hunan University Changsha China Medical Experiment Research Center Xiangya Hospital Central South University Changsha China Key Laboratory of Cancer Proteomics of Chinese Ministry of Health Changsha China

The effects of drug treatment, gene transfection, and p53 RNA interference (RNAi) on level of ING1 mRNA in tumor cells were quantitatively detected with the help of ING1 molecular beacon (MB)/cRNA standard curve based on MB detection technology. Results showed that the level of ING1 mRNA could be upregulated by 5-FU treatment or ING1 transfection in low expression cell line of MCF-7 and be inhibited by silencing p53 with RNAi technology in normal expression cell line of CNE2. The level of ING1 varied from 7.7×10?16 to 53.4× 10?16 mol/μg total RNA of tumor cells. The results not only provided evidence for the regulation effects of gene expression but also were applied to investigat- ing the interaction of multigenes on signal transduc- tion pathway.

关键词： ING1 RT-PCR 定量分析分子信号 mRNA