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991.
This review summarizes recent advances in electrochemical biosensors based on carbon nanotubes (CNTs) and carbon nanofibers (CNFs) with an emphasis on applications of CNTs. CNTs and CNFs have unique electric, electrocatalytic and mechanical properties, which make them efficient materials for developing electrochemical biosensors.We discuss functionalizing CNTs for biosensors. We review electrochemical biosensors based on CNTs and their various applications (e.g., measurement of small biological molecules and environmental pollutants, detection of DNA, and immunosensing of disease biomarkers). Moreover, we outline the development of electrochemical biosensors based on CNFs and their applications. Finally, we discuss some future applications of CNTs. 相似文献
992.
The electrophoretic mobility and catalytic activity of individual molecules of Escherichia coli beta-galactosidase were measured using CE-LIF detection. Both the mobility and activity were reproducible for each molecule but differed between individual molecules. Assays were performed using uncoated capillaries and capillaries coated with different polymers, using enzymes from different sources and by three different experimental protocols. In all cases the observed ranges in electrophoretic mobilities were similar. The observed range in the electrophoretic mobility may be explained by structural microheterogeneity resulting in a gain or loss of up to 1.6 suppressed charge units. There was no observed relationship between the observed activities and electrophoretic mobilities. If the finding that individual beta-galactosidase molecules have heterogeneous electrophoretic mobility can be extended to other proteins, this may limit the resolution possible for capillary zone electrophoresis protein separations. 相似文献
993.
构建大菜粉蝶Lipocalin蛋白家族中的BBP蛋白突变文库, 依据基因序列, 分别设计10条和12条引物, 通过PCR重叠延伸法得到包含随机突变蛋白BBP的基因序列, 并重组到噬菌粒载体pCANTAB5E中构建Lipocalin突变文库, 库容达到4.0×109. 以偶联分子BSA-克百威和OVA-克百威为靶分子, 采用柱式和平皿式交叉法对Lipocalin文库进行了筛选, 用竞争洗脱法洗脱特异结合活性的噬菌体. 经过3轮筛选, 从第3轮的洗脱液中随机挑选了10个重组克隆, 用Dot-blotting法检测出K7 anticalin分子能与克百威特异结合. 为研发克百威的Anticalin类检测试剂盒提供了候选分子, 也为拓宽Lipocalin文库在有害小分子检测方面的应用奠定了基础. 相似文献
994.
2,6-二甲基吡啶经氧化、酯化、Claisen酯缩合后制得新型化合物2-乙酯基-6-乙酰基吡啶(4), 用其作为前驱体, 与一系列小分子脂肪胺: 甲胺、乙胺、乙二胺在微波条件下生成3个吡啶酰胺化合物5, 6, 7. 通过元素分析, 1H NMR, IR和MS对这些化合物进行了表征. 对6-乙酰基-N-甲基吡啶-2-甲酰胺(5)的X射线晶体衍射研究表明: 其属于正交晶系, Pca2(1)空间群, 晶胞参数a=2.2784(2) nm, b=0.4350(4) nm, c=0.9267(3) nm; α=β=γ=90°; Dc=1.288 Mg•m-3, V=0.91856(14) nm3. 实验还发现: 2-乙酯基-6-乙酰基吡啶与脂肪胺及芳香胺缩合时会发生两类不同的反应, 小分子脂肪胺选择与酯基发生胺解反应, 而芳香胺则率先在乙酰基上发生席夫碱缩合. 对这两类有趣的反应机理进行了深入探讨. 相似文献
995.
通过多步反应合成了一种新型的具有“双极(bipolar)”性质和发光性能的以N原子为中心的星型有机小分子低聚物——三(4-(5-(4-(5-(4-(二苯胺基)苯基)-1,3,4-噁二唑-2)苯基)-1,3,4-噁二唑-2)苯基)胺. 用1H NMR, MS和元素分析进行了表征, 研究了化合物的热稳定性和固体粉末的光致发光性质, 并用循环伏安法测定了其电化学性能. 结果表明, 这种合成的同时具备空穴传导和电子输入双重功能基团的星型有机小分子光致发光性能优良(量子效率92%), 热稳定性好, 可以作为制作有机电致发光器件的候选材料. 相似文献
996.
997.
Stephen P Vijayan R Bhat A Subbarao N Bamezai RN 《Journal of computer-aided molecular design》2008,22(9):647-660
Pyruvate phosphate dikinase (PPDK) is the key enzyme essential for the glycolytic pathway in most common and perilous parasite Entamoeba histolytica. Inhibiting the function of this enzyme could control the wide spread of intestinal infections caused by Entamoeba histolytica in humans. With this objective, we modeled the three dimensional structure of the PPDK protein. We used templates with 51% identity and 67% similarity to employ homology-modeling approach. Stereo chemical quality of protein structure was validated by protein structure validation program PROCHECK and VERIFY3D. Experimental proof available in literature along with the in silico studies indicated Lys21, Arg91, Asp323, Glu325 and Gln337 to be the probable active sites in the target protein. Virtual screening was carried out using the genetic docking algorithm GOLD and a consensus scoring function X-Score to substantiate the prediction. The small molecule libraries (ChemDivision database, Diversity dataset, Kinase inhibitor database) were used for screening process. Along with the high scoring results, the interaction studies provided promising ligands for future experimental screening to inhibit the function of PPDK in Entamoeba histolytica. Further, the phylogeny study was carried out to assess the possibility of using the proposed ligands as inhibitors in related pathogens. 相似文献
998.
Jun Wang Cui Qin Li Shu Yan Zhang Fang Sun Teng Jie Ge 《中国化学快报》2008,19(1):43-46
Dendritic molecules with dodecyl groups as the hyperbranchs were synthesized in methanol by Michael addition with dodecylamine and methyl acrylate as raw materials. This new-type dendritic molecules were called vividly "broom molecules" in this report. The surface tension of the aqueous solution of broom molecule terminated amino group was measured by using the dropvolume method. The demulsification performance of the broom molecules for the oil/water (O/W) simulated crude oil emulsion was examined. The experimental results revealed that, as a new-type of surfactants, the broom molecules terminated amino groups showed demulsification for the O/W simulated crude oil emulsion. 2007 Jun Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved. 相似文献
999.
Liu FL Wang CH 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,70(5):1141-1145
Bonding, vibrational and magnetic properties of the cage-like molecule C(24)O(12) are studied by DFT calculations. Infrared- and Raman-active vibrational frequencies of the cage-like molecule C(24)O(12) are assigned. Two (13)C and one (17)O nuclear magnetic resonance (NMR) spectral signals of the cage-like molecule C(24)O(12) are characterized. Heat of formation of the cage-like molecule C(24)O(12) is estimated. Compared to C(60) and the cage-like molecule C(24)O(12), only from the thermodynamic points of view, C(24)O(12) is more stable than C(60). Thus we believe that the cage-like molecule C(24)O(12) has sufficient stability to allow its experimental preparation. We proposed that it could be synthesized by using the condensation of molecules C(6)(OH)(6) and C(12)Cl(12). Since the symmetry of C(24)O(12) is D(6), it is a chiral molecule. 相似文献
1000.
Xiaodan Yu Yihang Guo Kexin Li Xia Yang Leilei Xu Yingna Guo Jianglei Hu 《Journal of molecular catalysis. A, Chemical》2008,290(1-2):44-53
A series of insoluble cesium partly substituted Wells–Dawson type heteropolyacids, CsxH6−xP2W18O62 (x = 1.5–6.0), were synthesized and characterized using the techniques including UV–vis/DRS, FT-IR, XRD, XPS, and N2 porosimetry. As the unique and reusable solid acid catalysts, CsxH6−xP2W18O62 salts were applied to produce diphenolic acid by the condensation reaction of phenol with bio-platform molecule, levulinic acid. For comparison, cesium partly substituted Keggin type heteropolyacids (CsxH3−xPW12O40, x = 1.0–3.0), HCl, HZSM-5, and MCM-49 were also tested. Influences on the catalytic activity and selectivity were considered for factors including solvent, molar ratio of phenol to levulinic acid, amount of catalyst, reaction temperature, stirring speed, and reaction time. The experimental results demonstrated that both Cs1.5H4.5P2W18O62and Cs2.5H0.5PW12O40 exhibited excellent catalytic performance under solvent-free conditions. Furthermore, both selectivity and activity of Cs1.5H4.5P2W18O62 were higher than those of Cs2.5H0.5PW12O40. Reasons for the different catalytic behaviors between two types of cesium partly substituted heteropolyacids were investigated. 相似文献