两种NADH电化学检测方法的研究

发布时间：2018-05-06 02:36

本文选题：NADH + 3-氨基苯硼　；参考：《西北大学》2017年硕士论文

【摘要】：烟酰胺腺嘌呤二核苷酸(NADH)是人体中最重要辅酶之一,在人体的许多氧化还原反应中起着传递电子和质子的作用,研究NADH的电化学氧化对了解生命体系的电荷转移有着非常重要的意义。但由于NADH在裸电极表面的过电位较高,因此,在分析实际样品时会受到许多电活性物质的干扰,从而导致电极表面钝化、灵敏度降低以及重现性变差等问题。通过对电极表面进行修饰,不仅可以降低NADH的过电位,同时也可以避免干扰物质的影响。本论文基于硼亲作用实现NADH在电极表面的富集,结合吩嗪硫酸甲酯(PMS)对NADH的催化,实现对了在低电位下NADH的高灵敏检测;研究了氧化还原介体与二价阳离子对NADH的协同电催化作用;共分为三章:1.第一章主要对NADH及其在人体的作用以及NADH电化学传感器的研究进展进行了简单的介绍。2.第二章采用硼酸功能化多壁碳纳米管(MWCNTs)吸附吩嗪硫酸甲酯(PMS)作为电极修饰材料,构建了低电位高灵敏的NADH电化学传感器。硼酸作为识别单元可有效实现NADH在电极表面的富集;同时,电极表面吸附的PMS对富集的NADH产生电催化作用。该传感器不仅具有较高的灵敏度,而且可在较低电位下实现检测,有效地避免了共存物质的干扰。3.第三章研究了氧化还原介体与二价阳离子对NADH的协同电催化作用。将PMS固定在MWCNTs和离子液体(IL)复合电极表面,MWCNTs大的比表面积增加了PMS在电极表面的负载量,IL较高的导电性加速了 NADH与电极之间的电子转移。在以上修饰电极上研究了七种二价阳离子对NADH的电催化作用,研究表明,Ca~(2+) 的催化效果最好,催化电流增大了 2.3倍,从而实现了对NADH高灵敏的电化学检测。
[Abstract]:Nicotinamide adenine dinucleotide (NADH) is one of the most important coenzymes in human body and plays an important role in the transport of electrons and protons in many redox reactions. It is very important to study the electrochemical oxidation of NADH for understanding the charge transfer of the living system. However, due to the high overpotential of NADH on the bare electrode surface, many electroactive substances interfere with the analysis of the actual sample, which leads to the passivation of the electrode surface, the decrease of the sensitivity and the poor reproducibility of the electrode surface. By modifying the electrode surface, not only the overpotential of NADH can be reduced, but also the influence of interfering substances can be avoided. In this paper, the enrichment of NADH on the electrode surface based on boron lipophilicity and the catalytic activity of phenazine methyl ester sulfate (PMSs) on NADH were carried out to achieve the high sensitivity detection of NADH at low potential. The synergistic electrocatalytic effect of redox and divalent cations on NADH was studied, which was divided into three chapters: 1: 1. In the first chapter, the research progress of NADH and its role in human body and the electrochemical sensor of NADH are briefly introduced. In chapter 2, a low potential and high sensitivity NADH electrochemical sensor was constructed by using boric acid functionalized multiwalled carbon nanotubes (MWCNTs) to adsorb Phenazine Methyl Sulfate (Phenazine Sulfate) as electrode modified materials. Boric acid can effectively realize the enrichment of NADH on the electrode surface and the PMS adsorbed on the electrode surface can produce electrocatalytic effect on the enriched NADH. The sensor not only has high sensitivity, but also can be detected at lower potential, effectively avoiding the interference of coexisting substances. 3. In chapter 3, the synergistic electrocatalysis of NADH by redox and divalent cations was studied. The large specific surface area of PMS on the surface of MWCNTs and ionic liquid PMS composite electrode increases the loading amount of PMS on the electrode surface and the high conductivity of IL accelerates the electron transfer between NADH and the electrode. The electrocatalytic effect of seven kinds of divalent cations on NADH was studied at the above modified electrode. The results showed that the catalytic effect was the best, and the catalytic current increased 2.3 times, thus the highly sensitive electrochemical detection of NADH was realized.
【学位授予单位】：西北大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：Q75;O657.1

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