【作者】 韩军英；

【导师】 孙伟；

【作者基本信息】 青岛科技大学 ， 物理化学， 2005， 硕士

【摘要】 蛋白质是生物体的重要组成部分,它可以和许多内源外源性物质发生相互作用,蛋白质的分析测定是生化分析、临床监测、食品检测等方面的重要内容。电分析化学是一种有效研究生物大分子结构与功能的手段,本论文将蛋白质的分析检测同电分析化学的内容相结合,开展了蛋白质电化学探针的研究及分析应用方向的研究工作。本论文主要包括以下内容: 1.开展了蛋白质的电化学探针的研究。以滴汞电极、静汞电极等为工作电极,采用线扫伏安法、循环伏安法等电化学手段,结合紫外-可见分光光度法,根据蛋白质的结构特点和与有机小分子结合的本质,筛选了一些具有电化学活性的有机小分子如酸性铬蓝K、变色酸2B、变色酸2R、钍试剂、铬天青S等,以它们为电化学探针,以人血清白蛋白为模型,研究了它们与蛋白质的结合反应。在酸性条件下,这些有机小分子能够发生解离而带负电荷,而人血清白蛋白带正电荷,两者可以发生相互作用。这些有机小分子具有电化学活性,能够在电极上发生极谱还原反应,当加入蛋白质后,由于相互作用而导致了还原峰电流的降低,峰电流的降低值同蛋白质的加入量在一定浓度范围内呈现较好的线性关系。对结合反应条件和电化学检测条件进行了优化,考察了常见金属离子、氨基酸等物质对分析测定的干扰,在最佳条件下,建立了测定不同蛋白质的工作曲线,并将所建立的电化学分析新方法应用于正常人血清样品中蛋白质含量的测定,结果与经典的考马斯亮蓝G-250光度法一致,说明了本分析方法的准确性和可靠性。 2.对结合反应机理进行了电化学推导。考察了上述有机小分子在溶液中的电化学行为以及与蛋白质相互作用后溶液的电化学参数的变化情况,结果表明,加入蛋白质后,溶液的电化学参数如标准电极电位E~0,标准速率常数K_s和电子转移系数α等基本不发生变化,说明其与蛋白质发生结合后成生了一种非电化学活性的生物超分子复合物,降低了溶液中有机小分子的游离浓度,从而使有机小分子的还原峰电流降低。利用相关的电化学方程分别对结合反应的结合比和结合常数进行了求解。 3.初步开展了生物多糖物质肝素钠的电化学研究。选择了中性红为探针,更多还原

【Abstract】 Protein is an important substance in human body and it can easily bind with the inner and exo substances to influence the healthy of human. The qualitative and quantitative analysis of protein is also an important factor in biochemical and clinical assays. Electroanalytical chemistry is one of the most interesting research techniques that can be used to investigate the structures and mechanisms of biomolecules. This thesis combines with the analytical determination of protein with electroanalytical chemistry and focuses on the study of the electrochemical probes of protein and analytical application. The paper can be summarized as follows:1. The electrochemical probes of protein are carefully studied. The interaction of small molecules such as acid chrome blue K, chromotrope 2B, chromotrope 2R, thorin, chromazurol S were selected and used as electrochemical probes for the determination of protein with different electrochemical method such as linear sweep voltammetry, cyclic voltammetry and UV-Vis spectrophotometric method. The small organic molecules are electrochemical active and can be reduced on the mercury electrode. On the addition of protein, the reduction peak current decreases because of interaction. The decrease of reductive peak current is proportional to the protein concentration. The conditions of binding reaction and the electrochemical determination were optimized. The influences of coexisting substances such as metal ions and amino acids were tested. Under the optimal conditions the working curves for different proteins were established and the proposed methods were further applied to the detection of the content of albumin in healthy human serum samples. The更多还原