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Fluorescence dynamics of interactions between polyamide PyPyPyβDp and DNA

Science China chemistry 2006年第1期49卷 75-80页

作者： ZHANG Huijuan1,2, WANG Jin3. WU Yishi1, YUAN Gu3. AI Xicheng1, WANG Li4.& ZHANG Jianping1 1. State Key Laboratory for Structural chemistry of Unstable and Stable Species, Institute of chemistry, Chinese Academy of Sciences, Beijing {4., China 2. School of Life Science and Technology, Beijing Institute of Technology, Beijing 100081, China {3., peking university, Beijing {4., China 4. Center for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing {4., China Correspondence should be addressed to Ai Xicheng and Zhang Jianping 1. State Key Laboratory for Structural chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. School of Life Science and Technology Beijing Institute of Technology Beijing 100081 China 3. college of chemistry and molecular engineering Peking University Beijing 100080 China 4. Center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The photophysical properties of the polyamide PyPyPyβDp (PPP) were investigated by means of steady-state absorption and fluorescence spectroscopies, as well as time-resolved fluo-rescence spectroscopy. It was found that the excited-state properties of PPP are very sensitive to solvents. In TKMC buffer PPP exhibited weak fluorescence with a decay time constant of 16 ps, while with the decrease of the solvent polarity PPP showed the blue-shifted peak position, increased inten-sity and lengthened life-time for its fluorescence behavior. In the presence of calf thymus DNA, it was observed that the fluorescence intensity was enhanced and the fluorescence lifetime increased from 16 to 3. ps for PPP, which verified that PPP bound into the minor groove of DNA duplex.

关键词： polyamide (PPP), calf thymus DNA (ctDNA), time-resolved fluorescence spectroscopy, recognition dynamics.

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Theoretical study on the reaction mechanism of(CH_3._3.O+CO

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Science China chemistry 2005年第1期48卷 18-24页

作者： ZHAO Hongmei1,2,3. SUN Chengke1,4. ZHANG Rongchang3. XI Hongmin3.& LI Zonghe1 1. Department of chemistry, Beijing Normal {4., Beijing 100875, China 2. The Laboratory of molecular Reaction Dynamics, Institute of chemistry, Chinese Academy of Sciences, Beijing 100080, China 3. Department of chemistry, Beihua {4., Jilin 13.013. China 4. Department of chemistry, Qujing Normal {4., Yunnan 655000, China 1. Department of chemistry Beijing Normal University 100875 Beijing China 2. The Laboratory of molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China 3. Department of chemistry Beihua University 132013 Jilin China 4. Department of chemistry Qujing Normal University 655000 Yunnan China

The reaction mechanism of (CH3.3.O with CO has been theoretically investigated using density-functional theory (DFT) calculations at B3.YP/6-3.G* level. In order to get more reliable energy values the single-point energy is evaluated at CCSD (T)/6-3.++G** level. The results show that the reaction is multi-channel and the reaction of (CH3.3.O radical with CO mostly produces (CH3.3. + CO2. The reaction could play a role in eliminating air pollution.

关键词： DFT, B3.YP, (CH3.3.O, radical.

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Distinguishing malignant from normal stomach tissues and its in vivo, in situ measurement in operating process using FTIR Fiber-Optic techniques

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Science China chemistry 2005年第2期48卷 167-175页

作者： XU Yizhuang1, YANG Limin1, XU Zhi3. ZHAO Ying2, LING Xiaofeng3. LI Qingbo1, WANG Jiansheng4. ZHANG Nengwei3. ZHANG Yuanfu1 & WU Jinguang1 1. The State Key Laboratory of Rare Earth Materials and Applications, college of {4. and molecular {3., peking university, Beijing 100871, China 2. Institute of {4., Chinese Academy of Sciences, Beijing 100080, China 3. Department of Surgery, Third Hospital, peking university, Beijing 100083. China 4. Department of Oncology Surgery, the First Hospital of Xi’an Jiaotong university, Xi’an 710061, China Correspondence should be addressed to Wu Jinguang (email: wujg@***) 1. The State Key Laboratory of Rare Earth Materials and Applications College of Chemistry and Molecular Engineering Peking University 100871 Beijing China 2. Department of Surgery Third Hospital Peking University 100083 Beijing China 3. Institute of chemistry Chinese Academy of Sciences 100080 Beijing China 4. Department of Oncology Surgery the First Hospital of Xi’an Jiaotong University 710061 Xi’an China

Gastric tissue samples were studied using mid-IR fiber-optic attenuated total reflectance (ATR) spectroscopy. FTIR spectra of 90 tissue samples from 4. patients, including 3. normal and 58 malignant tissue samples, were chosen as examples. Malignancy was usually characterized by the absence of CH and C=O bands, a weak amide II band near 154. cm-1, a shift of the amide I band to lower wave number, a decrease in the ～14.0 cm-1 peak to less than the～14.0 cm-1 peak. Subtraction spectra indicate that the amide I and amide II bands of normal and malignant tissues have larger differences in peak positions and relative intensities. The statistical analysis results confirm this conclusion. The results indicate that FTIR fiber optic techniques provide important information about cancerous tissue of the stomach, which can be used to differentiate the malignant tissue from the normal tissue. Based on the above results we successfully realize the detection of the tumor tissues of digestive tract in vivo and in situ. And the results of detection cancer near operating room and in vivo and in situ in the operating room are consistent with the conclusions for the samples stored in liquid N2, which is the basis for the clinical application.

关键词： FTIR, Fiber-Optics, stomach tissues, cancer, diagnosis.

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Synthesis and Crystal Structure of 4.6Di-tert-butyl-2-hydroxy-3.(N-1-phenylethyliminomethyl) phenyl bis(triphenylphosphine)palladium bromide

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Chinese Journal of Structural chemistry 1999年第4期18卷 54-59页

作者： XU JiaXi\ ZHANG ZeYing\= (college of chemistry and molecular {3.,{4., Beijing 100871, China) Coll. of Chem. and Molec. Eng. Peking University Beijing 100871 China

１ＩＮＴＲＯＤＵＣＴＩＯＮＰａｌａｄｉｕｍｃｏｍｐｌｅｘｅｓｓｕｃｈａｓｔｅｔｒａｋｉｓ（ｔｒｉｐｈｅｎｙｌｐｈｏｓｐｈｉｎｅ）ｐａｌａｄｉｕｍａｒｅａｋｉｎｄｏｆｉｍｐｏｒｔａｎｔｃａｔａｌｙｓｔｓｉｎｔｈｅｒｅａ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＰａｌａｄｉｕｍｃｏｍｐｌｅｘｅｓｓｕｃｈａｓｔｅｔｒａｋｉｓ（ｔｒｉｐｈｅｎｙｌｐｈｏｓｐｈｉｎｅ）ｐａｌａｄｉｕｍａｒｅａｋｉｎｄｏｆｉｍｐｏｒｔａｎｔｃａｔａｌｙｓｔｓｉｎｔｈｅｒｅａｃｔｉｏｎｏｆｃａｒｂｏｎｃａｒ...

关键词： palladium complex synthesis molecular structure crystal structure

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Applications of functionalized ionic liquids

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Science China chemistry 2006年第5期49卷 385-401页

作者： LI Xuehui1, ZHAO Dongbin2,3. FEI Zhaofu2 & WANG Lefu1 1. Department of Chemical engineering, Guangdong Provincial Laboratory of Green Chemical Technology, South China Uni-versity of Technology, Guangzhou 51064., China 2. Swiss Federal Institute of Technology, Lausanne, EPFL, CH-1015 Lausanne, Switzerland 3. PKU Green chemistry Center, Beijing National Laboratory for {4. Sciences, {3. of chemistry and {4. engineering, peking university, Beijing 100871, China 1. Department of Chemical engineering Guangdong Provincial Laboratory of Green Chemical Technology South China University of Technology Guangzhou 510641 China 2. Lausanne EPFL Swiss Federal Institute of Technology CH-1015 Lausanne Switzerland 3. PKU Green chemistry Center Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

Recent developments of the synthesis and applications of functionalized ionic liquids (including dual-functionalized ionic liquids) have been highlighted in this review. Ionic liquids are at-tracting attention as alternative solvents in green chemistry, but as more functionalized ILs are pre-pared, a greater number of applications in increasingly diverse fields are found.

关键词： ionic liquids functionalized ionic liquids dual-functionallzed ionicliquids reaction media asymmetric synthesis nano-materials porous materials lubricants flue-gas desulfurization oil desul-furization

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Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2, ZHANG Jiao qiang 3. (1. Department of chemistry,Northwest university, Xi′an 710065, China 2. Department of chemistry and Chemical {3., Baoji college of Arts and Science, Baoji 721007, China 3. Department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

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Synthesis,Structure and Antitumor Activities of Tridccapeptide PSPP3.from Papaver Somniferum Pollen

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Chinese Chemical Letters 1999年第2期10卷 115-116页

作者： Jia Xi XU Sheng JIN(college of chemistry and molecular {3.,{4., Beijing 100871) Coll. of Chem. and Molec. Eng. Peking University Beijing 100871 China

Five analogs and five segments of the Papavor Somniferum pollen tridecapeptidePSPP3.were designed and synthesized by using solid-phase peptide synthesis method. Theirinhibitive activities to human liver tumor cell Bel-74.2 were assayed by MTT method and theirsecondary structures in solution were determined by CD spectra. The relationship of the structureand activity was discussed.

关键词： Pollen peptide anti-tumor activity structure and activity

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Status of study on biological and toxicological effects of nanoscale materials

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Science China chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2 & JIA Guang3.1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab), Institute of High Energy Physics, Chi-nese Academy of Sciences, Beijing 10004., China 2. college of chemistry and molecular {3., peking university, Beijing 100871, China 3. Department of Occupational and Environmental Health Sciences, School of Public Health, peking university, Beijing 100083. China 1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences 100049 Beijing China 2. college of chemistry and molecular {3. Peking University 100871 Beijing China 3. Department of Occupational and Environmental Health Sciences School of Public Health Peking University 100083 Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

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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 {3.,{4., Beijing 100871, China college of chemistry and molecular {3. 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

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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 {3. {4.,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

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