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591.
Hirudin, a thrombin inhibitor, is a polypeptide of 65 amino acids. To check purity levels and perform pharmacokinetic studies of recombinant hirudin (r-hirudin), a specific and reproducible analysis method is required. Capillary electrophoresis (CE) is rapidly becoming an important procedure for the analysis of biological molecules. Recently, CE combined with immunoassay has emerged as a new analytical technique. CE-based immunoassay (CEIA) is a sensitive and specific method combining laser-induced fluorescence (LIF) and immunoassay. Therefore, in this study, we specifically investigated fluorescence labeling and determination of r-hirudin by CEIA with a LIF detector using labeled r-hirudin and polyclonal antibody. r-Hirudin was labeled with fluorescein isothiocyanate (FITC). FITC-labeled r-hirudin was purified using high-performance liquid chromatography (HPLC). The method is based on preincubation of r-hirudin and antibody for 20 min, followed by CE analysis using an uncoated capillary. Free and bound r-hirudin were separated within 5 min using CE with high reproducibility. This study demonstrated that the CEIA method could be applied to quantitative analysis of r-hirudin in biological fluids. 相似文献
592.
Jonathan P. Markham Ban Wang Dr. Edwin D. Stevens Dr. Stuart C. Burris Dr. Yongming Deng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(26):6638-6644
A photocatalyzed ortho-alkylation of pyridine N-oxide with ynamides and arylacetylenes has been developed, which yields a series of α-(2-pyridinyl) benzyl amides/ketones. Mechanistic studies, including electrochemical studies, radical-trapping experiments, and Stern–Volmer fluorescence quenching studies demonstrate that pyridine N-oxide serves as both a redox auxiliary and radical acceptor to achieve the mild photocatalytic single-electron oxidation of carbon–carbon triple bonds with the generation of a cationic vinyl radical intermediate. 相似文献
593.
Wenliang Fan Wang Yanlai Zhu Jun Ban S. L. 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2018,92(10):2086-2091
Russian Journal of Physical Chemistry A - The copper zinc tin sulfide (CZTS) thin films are prepared by a promising non vacuum compacting process based on ball milling and coating technique. The... 相似文献
594.
595.
Xu Yuli Zhang Kang Wang Cheng Zhu Qiqi Luo JiaQi Chen Fang Xiao Fangzhu Peng Guowen 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(3):1145-1155
Journal of Radioanalytical and Nuclear Chemistry - A novel material called m-carboxyphenyl azo calix[4]arene amine oxime derivatives (M-CCAOD) was synthesized by diazotization-coupling reaction and... 相似文献
596.
Li-Ping Wang Guang Li Wen-Zhi Li Chao-Lei Ban Yu-Chao Li Cong Guo Meng-Meng Zhang Ling-Yun Liu Na-Na Lu Meng-Zhu Zheng 《中国化学快报》2014,25(12):1620-1624
A novel copolymer with fluorescence properties in mesoporous silica SBA-15 was prepared via a combination of surface-initiated reversible addition-fragmentation chain transfer(RAFT) polymerization and "click" chemistry.A sufficient amount of peroxide groups were introduced into mesoporous silica SBA-15 channel pores and were further used to initiate the RAFT polymerization of styrene and 4-vinylbenzyl azide,resulting in SBA-15 supported polystyrene-co-poly(4-vinylbenzyl azide) copolymer(PS-co-PVBA/SBA-15) hybrid material.The samples were characterized by Fourier transform infrared spectroscopy(FT-IR),transmission electron microscopy(TEM),thermogravimetry analysis(TGA),N_2 adsorption-desorption isotherms and X-ray diffraction(XRD),respectively.The results show that the styrene and 4-vinylbenzyl azide had copolymerized inside mesoporous silica SBA-15.Subsequently,Npropargyl-carbazole(PC) was connected to PS-co-PVBA/SBA-15 hybrid material via "click" reaction,resulting in PS-co-PVBC/SBA-15 with carbazole side groups hybrid material.The fluorescence spectrum is dominated by a broad band from 350 nm to 400 nm in narrow region and the maximum peak is 362 nm,indicating the characteristic absorption of the carbazole group of PS-co-PVBC/SBA-15 hybrid material. 相似文献
597.
598.
Nonlinear Dynamics - Flexible robots with controllable mechanisms have advantages over common tandem robots in vibration magnitude, residual vibration time, working speed, and efficiency. However,... 相似文献
599.
Initial dynamic mechanical and dielectric studies on a systematic series of γ glutamate polypeptides
An-Lac Nguyen Ban The Vu Garth L. Wilkes 《Journal of Macromolecular Science: Physics》2013,52(3):367-389
The complementary dynamic mechanical and dielectric methods have been extensively employed in the characterization of organic polymers. While the former method is sensitive to molecular motions that affect the mechanical properties, the latter has the advantage of detecting molecular motions that involve dipole oscillation. We have used both methods simultaneously within this study in order to help understand a portion of the molecular transitions that occur within a series of synthetic polypeptides. 相似文献
600.
ABSTRACTOptoelectronic devices, widely used in high energy and nuclear physics applications, suffer severe radiation damage that leads to degradations in its efficiency. In this paper, the influence of gamma radiation (137Ce source) and beta radiation (90Sr source) on the photoelectric parameters of the Si solar cell, based on the I–V characterization at different irradiation exposer, has been studied. The penetrating radiation produces defects in the base material, may be activated during its lifetime, becoming traps for electron–hole pairs produced optically and, this will, decrease the efficiency of the solar cell. The main objective of the paper is to study and measure changes in the I–V characteristics of solar cells, such as efficiency, maximum current, maximum power, and efficiency, due to the exposure of solar systems to different doses of γ and β irradiations. 相似文献