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science china chemistry 2008年第11期51卷 1066-1073页

作者： ZHANG YongChun, YANG Tao, ZHOU Na, ZHANG Wei & JIAO Kui college of chemistry and molecular Engineering, Qingdao university of science and Technology, Qingdao 266042, china 1. college of chemistry and molecular Engineering Qingdao University of Science and Technology Qingdao 266042 China

Gold nanoparticles (nano Au)/titanium dioxide (TiO2) hollow microsphere membranes were prepared on the carbon paste electrode (CPE) for enhancing the sensitivity of DNA hybridization detection. The immobilization of nano Au and TiO2 microsphere was investigated with cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The hybridization events were monitored with EIS us-ing [Fe(CN)6]3-/4- as indicator. The sequence-specific DNA of the 35S promoter from cauliflower mosaic virus (CaMV35S) gene was detected with this DNA electrochemical sensor. The dynamic detection range was from 1.0×10-12 to 1.0×10-8 mol/L DNA and a detection limit of 2.3×10-13 mol/L could be ob-tained. The polymerase chain reaction (PCR) amplification of the terminator of nopaline synthase (NOS) gene from the real sample of a kind of transgenic soybean was also satisfactorily detected.

关键词： Au nanoparticle TiO_2 hollow microsphere DNA electrochemical biosensor CaMV35S gene NOS gene

STABILITY OF POLY(N,N'-METHYLENEBISACRYLAMIDE-co-4-VINYLPYRIDINE)MICROGEL DISPERSION AND ADJUSTMENT OF THE HYDROPHOBICITY IN THE MICROGELS

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Chinese Journal of Polymer science 2005年第6期23卷 635-642页

作者： Qing-de Chen Xing-hai Shen and Hong-cheng Gao Department of Applied chemistry,college of chemistry and molecular Engineering,Peking university,Beijing 100871,china Peking Univ Dept Appl Chem Coll Chem & Mol Engn Beijing 100871 Peoples R China

In the UV-Vis spectra of pure light-scattering systems, there is an exponential relationship between absorbance and wavelength （A = Kλ^-n）. Here, the exponent n is named as flocculation-coagulation parameter. In the present paper, the effects of different additives on the stability of poly（N,N＇-methylenebisacrylamide-co-4-vinylpyridine）（poly（Bis-co-4-VP）） microgel dispersion were studied in detail via this parameter. The results showed that the stability of the dispersion mainly comes from the ionization of pyridine groups, making the microgel positively charged on its surface. This was confirmed by the measurement of Zeta potential and the result of conductometric titration. The result of fluorescence analysis indicated that the hydrophobicity in the microgels is enhanced with the increase in total 4-VP unit content.

关键词： Microgel dispersion(s) 4-Vinylpyridine Flocculation-coagulation parameter Zeta potential

Surface modification of hydrophobic NaYF_4:Yb,Er upconversion nanophosphors and their applications for immunoassay

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science china chemistry 2011年第8期54卷 1292-1297页

作者： LIU ChengHui, WANG Zhe, WANG XiaoKe & LI ZhengPing Key Laboratory of Medicinal chemistry and molecular Diagnosis, Ministry of Education college of chemistry and Environmental science, Hebei university, Baoding 071002, china 1. Key Laboratory of Medicinal chemistry and molecular Diagnosis Ministry of Education College of Chemistry and Environmental Science Hebei University Baoding 071002 China

β-NaYFa：Yb,Er upconversion nanophosphor （UCNP） is known as one of the most efficient NIR-to-visible upconversion mate- dais, which shows great potential in bioanalytical chemistry and bioimaging. However, its applications are greatly limited due to its low water dispersibility and thus poor biocompatibility. In this paper, poly（acrylic acid）（PAA）-based ligand exchange strategies are carded out to modify oleic acid-capped hydrophobic β-NaYF4：Yb,Er UCNPs into hydrophilic ones. After efficient surface modification, the presence of free carboxylic acid groups on the surfaces of UCNPs results in high solubility in water, and also allows further conjugation with NH2-containing biomolecules. Facilitated by the covalent linkage between the -COOH groups on UCNPs surfaces and -NHz groups in antigen/antibody, a sensitive immunosensor is constructed by using PAA-functionalized β-NaYFa：Yb,Er UCNPs as biolabels. Through monitoring the upconversion fluorescence intensity or fluorescent imaging of the final immunocomplexes, high sensitivity is achieved for the proposed immunoassay and as low as 0.1 ng/mL goat anti-human immunoglobulin G （IgG） can be detected, which suggests that PAA-modified UCNPs may serve as an ideal candidate for use as bioanalysis and bioimaging probes.

关键词： surface modification upconversion nanophosphor ligand exchange immunoassay bioimaging

SYNTHESIS AND CHARACTERIZATION OF A NOVEL BLUE LIGHT EMITTING ROD-COIL DIBLOCK OLIGOMER

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Chinese Journal of Polymer science 2002年第5期20卷 401-407页

作者： Lifang Yang Haifeng He Hongqing Cao Xinhua Wan Qi-feng Zhou Department of Polymer science & Engineering college of chemistry & molecular Engineering Peking university Beijing 100871, china Peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China

Four new rod-coil diblock molecules, which had well-defined para-phenylene oligomers (PPP, from biphenyl to quinquephenyl) as rigid segments and poly(ethylene oxide) (PEO, M-w ca. 750) as flexible segments, were synthesized. The chemical structure and the number of repeating unit in PEO coil and PPP rod were characterized by H-1-NMR and MALDI-TOF mass spectrometry. The diblock oligomers showed good solubility in common organic solvents and aggregated in water as characterized by a blue shift in UV-vis absorption spectra, a red shift in emission spectra, quenching of the fluorescence and formation of the microfibrilla and fractal-like structures. The formation of different supramolecular structures meant that this effort might lead to commercial important highly organized functional materials.

关键词： rod-coil diblock oligomer MALDI-TOF mass spectrometry microfibrilla aggregate fractal-like pattern

Inhibitory effect of picroside Ⅱ on hepatocyte apoptosis

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Acta Pharmacologica Sinica 2005年第6期26卷 729-736页

作者： Hua GAO, Ya-wei ZHOU~2 college of chemistry and molecular Engineering, Peking university, Beijing 100871, china college of chemistry and molecular Engineering Peking University Beijing China

Aim: To investigate the influence of picroside on hepatocyte apoptosis and its mechanism. Methods: Morphological changes and quantification of apoptotic cells were determined under transmission electron microscopy and flow cytometry respectively. DNA fragmentation was visualized by agarose gel electrophoresis. Semi-quantitative reverse transcription-PCR (RT-PCR) was used to analyze the expression of bcl-2 and bax genes. The content of manganese-superoxide dismutase (SOD) in liver mitochondria was detected by the Marland method. The content of malonic aldehyde (MDA) and the protein level in liver tissue were determined by thiobarbituric acid colorimetry and Lowry method. Results: Picroside decreased the levels of alanine aminotransferase and aspartate aminotransferase in the serum resulting from acute-liver injured mice induced with D-GalN and LPS; it also reduced the content of MDA, and thus, enhanced the activity of SOD. Picroside 0 mg/kg was found to protect hepatocytes against apoptosis in a dose-dependent manner; it up-regulated the expression of bcl-2 genes, thus increased the bcl-2/bax ratio. Conclusion: Picroside 鈪an protect hepatocytes against injury and prevent hepatocytes from apoptosis. It might by upregulating the bcl-2 gene expression and antioxidation.

关键词： picroside Ⅱ hepatocytes apoptosis oxidative stress bcl-2 genes bax genes

Sensitive Determination of DNA by RLS Enhancement of Metal Ions

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wuhan university Journal of Natural sciences 2004年第2期9卷 234-238页

作者： Huang Jian-ping 1,2, Chen Fang 1, Ai Xin-ping 1, He Zhi-ke 1 1. college of chemistry and molecular sciences, wuhan university, wuhan 430072, Hubei, china 2. Department of Environmental Engineering, Hubei Agricultural college, Jingzhou 434025, Hubei, china wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Hubei Agricultural college Department of Environmental Engineering Jingzhou Hubei China (GRID:grid.49470.3e) wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The interactions between metal ions and DNA have been studied by the resonance light scattering (RLS) spectra. In the acidic condition, the RLS signals of metal ions, especially the transition metal ions in group IB and IIB, were increased by DNA. And it is found that the enhancement of RLS signals is linear to the concentration of DNA, so the RLS method for DNA determination was proposed in the presence of Cu2+. On the optimum conditions, the linear range and the detect limit of ctDNA is 4×10?8–4×10?6 g· mL?1 and 1. 13×10?8 g·mL?1, respectively. The proposed method is successfully applied to determine the extracted plasmid DNA ofBacillus subtilis DB104. Key words resonance light scattering - DNA - metal ions CLC number O 657.3 Foundation item: Supported by National Natural science Foundation of china (20275028) and the National Key Basic Research and Development Program (973 Program 2002CB211800).Biography: Huang Jian-ping(1964-), male, Associate professor, research direction: bioanalysis.

关键词： resonance light scattering DNA metal ions

A Novel Polymethyl Methacrylate (PMMA)-TiO_2 Nanocomposite and Its Thermal and Photic Stability

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wuhan university Journal of Natural sciences 2006年第2期11卷 415-418页

作者： ZAN Ling LIU Zhongshi FA Wenjun PENG TianYou college of chemistry and molecular sciences Wuhan University Wuhan 430072 Hubei China

A new kind of polymethyl methacrylate （PMMA）-TiO2 nanocomposite was synthesized through polymerization. The thermal and photic stability of this PMMA TiO2 nanocomposites were investigated. The as prepared samples were characterized by scanning electron microscopy （SEM）, UV-Vis spectroscopy, differential thermal analysis （DTA） and the photo-induced weight loss, The results show that the photostability of the PMMA-TiO2 nanocomposite is higher than that of the pure PMMA under UV-light irradiation, The weight loss of the pure PMMA reaches 30 % after 300 h UVirradiation, while the composite only 0.3% under the identical experimental condition. The glass transition temperature （TR） of pure PMMA is only 80℃, while the Tg of the composite reaches 258℃. Compared with pure PMMA, the thermal stability of the composite is greatly enhanced.

关键词： polymethyl methacrylate ( PMMA )-TiO2 nanoeomposite polymerization thermal and photic stability

EFFECTS OF L-PHENYLALANINE ON THE RADIATION SYNTHESIS OF POLY(N,N'-METHYLENEBISACRYLAMIDE-co-4-VINYLPYRIDINE)(MICRO)GELS

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Chinese Journal of Polymer science 2005年第6期23卷 643-650页

The effects of L-phenylalanine （L-Phe） on the synthesis ofpoly（N,N＇-methylenebisacrylamide-co-4-vinylpyridine）（poly（Bis-co-4-VP））（micro）gels by γ-ray irradiation were studied. The addition of L-Phe could not only decrease the gelation dose （Dg） of the synthesis obviously, but also transform the morphology of copolymer from microgel to gel. In addition, the swelling ability of the （micro）gels was also affected in the presence of L-Phe. The decrease of Dg was ascribed to the effect of pH, while the transformation of the morphology was ascribed to the effect of L-Phe on the stability of the poly（Bis-co-4-VP） microgel. Such an effect was confirmed further as compared with the effects of L-alanine, L-glutamic acid, L-arginine, sulfuric acid and aqueous ammonia.

关键词： L-Phenylalanine γ-Ray irradiation Gelation dose Morphology transformation (Micro)gel

Immobilized chitosan as a selective absorbent for the nickel removal in water sample

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Journal of Environmental sciences 2003年第5期15卷 633-638页

作者： WU Jian min, WANG Yong yao (Department of chemistry, college of science, Zhejiang university, Hangzhou 310027, china. ) Department of chemistry College of Science Zhejiang University Hangzhou 310027 Chin

Method for preparation of chitosan immobilized on silica gel(CTS silica) was described. The CTS silica was used as absorbent for the absorption of nickel in water. The results showed that this absorbent had relatively high selectivity and strong affinity to nickel. The maximum absorption capacity for nickel can reach 667 mg/g of chitosan. Factors that affect the absorption capacity, such as pH, ion strength and the presence of calcium, EDTA and the mechanism of absorption were discussed in detail. The absorbent can be regenerated with acid and reused for several times. The recovery rate for nickel can reach 99 99%. This absorbent filled in a column can be used in nickel removal from wastewater and drinking water.

关键词： immobilized chitosan nickel wastewater treatment

Correlation of Behavior Changes and BOLD Signal in Alzheimer-like Rat Model

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 803-810页

作者： Zheng-Hui HU#, Xiao-Chuan WANG1#, Li-Yun LI3, Mai-Li LIU3, Rong LIU1, Zhiqun LING1, Qing TIAN1, Xiao-Wei TANG, Yi-Gen WU2*, and Jian-Zhi WANG1* Department of Physics and Bio-X disciplinary Laboratory, Zhejiang university, Hangzhou 310027,china 1 Department of Pathophysiology, Tongji Medical college, Huazhong university of science and Technology, wuhan 430030, china 2Institute of High Energy Physics and Key Laboratory of Nuclear Analysis Techniques, Chinese Academy of sciences, P.O. Box 918, Beijing 100039, china 3wuhan Institute of Physics and Mathematics, State Key Laboratory of Magnetic Resonance and Atomic and molecular Physics, Chinese Academy of sciences, wuhan 430071, china Department of Physics and Bio-X disciplinary Laboratory Zhejiang UniversityHangzhou 310027China Department of Pathophysiology Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030 China wuhan Institute of Physics and Mathematics State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Chinese Academy of SciencesWuhan 430071 China Institute of High Energy Physics and Key Laboratory of Nuclear Analysis Techniques Chinese Academy of SciencesP.O. Box 918 Beijing 100039 China

To explore a potential means for the early diagnosis of Alzheimer disease, we studied the relationship of resting T2* signal and tau hyperphosphorylation/spatial memory deficit. The rat model with tau hyperphosphorylation and spatial memory deficit was established by bilateral hippocampi injection of isoproterenol (IP). Then, the correlative alteration between resting T2* signal and spatial memory retention was assessed with blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) study and Morris Water Maze test, and Western blot was employed to confirm tau hyperphosphorylation. The analysis showed following results. (1) Tau phosphorylation at Ser396/Ser404 and Ser199/Ser202 was signifi- cantly increased in IP-injected rats as detected by PHF-1 and tau-1, respectively. (2) An AD-like spatial memory retention disturbance was induced at 24 h after isoproterenol injection. (3) A sensitivity threshold of resting T2* signal intensity, which separated the IP-treated rats from vehicle control, was obtained by applying linear regression analysis, and an estimated sensitivity statistical threshold was at 32.62. These results suggest that resting T2* signal may serve as a noninvasive quantitative marker in predicting AD-like spatial memory deficits and tau hyperphosphorylation.

关键词： Alzheimer disease (AD) functional magnetic resonance imaging (fMRI) isoproterenol (IP) Morris Water Maze diagnosis