几种神经递质电化学传感器构置及应用研究

【作者】 孙宇宏；

【导师】 郑晓晖；

【作者基本信息】 西北大学 ， 药物化学， 2013， 博士

【摘要】 构建分析性能优异的新型电化学传感界面是神经递质传感器研制的关键,本论文从磺酸偶氮类聚合物、石墨烯新型修饰材料的开发入手,构置了多种神经递质检测相关的修饰电极,研究了多巴胺等神经递质化合物在修饰电极表面的电化学行为,并建立了多巴胺、丹参素异丙酯等化合物的伏安分析新方法,该研究为探索神经递质类物质的高灵敏度、高选择性电化学传感界面提供了新思路,拓展了石墨烯及磺酸偶氮类物质的应用范围,对多巴胺相关的药物及制剂的分析检测、质量控制提供了简单易行且高效的分析方法。主要研究内容如下：1.采用电聚合方式,构置了四种磺酸偶氮类聚合物修饰电极,通过化合物聚合过程中电化学行为特点并结合电极表面的光谱学特征,对该类化合物的成膜机理进行推测；将四种聚合物修饰电极用于多巴胺神经递质的电化学检测中,对多巴胺在该类修饰电极表面的电化学催化过程进行研究,提出了该类聚合物结构中的醌腙类官能团进行电化学催化,同时磺酸基吸附的可能电化学过程；最后实现了四种修饰电极对多巴胺、对乙酰氨基酚、尿酸、L-色氨酸、肾上腺素的单独或同时测定。2.研究了含氮化合物柠嗪酸对氧化石墨烯的电还原过程的影响,发现该化合物能够显著提升氧化石墨烯电还原后材料的电催化性能,通过材料的光谱学及表面形态特征,结合近年来对石墨烯材料的研究进展,提出了柠嗪酸对氧化石墨烯的吸附造成不规则堆叠可能为电化学性能得以提升的原因,并将该电还原石墨烯修饰电极用于对多巴胺的电分析,实现了多巴胺的单独测定及多巴胺、尿酸的选择性测定。实验结果证明该材料具有较为优异的分析性能,对多巴胺及尿酸的检出限分别为9.0×10-8mol/L和9.0×10-7mol/L。3.利用构置的聚新胭脂红修饰电极对效应物质成分丹参素异丙酯在该电极上的电化学行为进行了研究,建立了检测丹参素异丙酯的电化学分析方法。实验结果表明,该方法具有较好的分析性能,对丹参素异丙酯分析的线性范围为0.4×10-6～2×10-5mol/L,检出限为1.0×10-7mol/L,优于紫外分光光度法,对丹参素异丙酯片剂进行了样品测定；同时利用该修饰电极对丹参素异丙酯与牛血清白蛋白之间的相互作用进行研究,结果表明丹参素异丙酯能够与牛血清白蛋白结合形成复合物,其结合常数为1.00×1010Lmol-1,结合位点数为2。更多还原

【Abstract】 Using new materials, including organic polymer and graphene in construction of high sensitive and selective electro-chemical sensors for neurotransmitters. In this dissertation, several kinds of electro-chemical sensors based on sulfonic azo dye and graphene materials were fabricated, and the behaviors of electro-chemistry and electro-catalysis for dopamime (DA), uric acid (UA), acetaminophen (AP), L-tryptophan (Trp) and epinephrine (EP) on these modified electrodes were investigated in details. These studies may be of great importance not only in the field of biomedical chemistry and neurochemistry but also for diagnostic and pathological research. The thesis consists of four chapters and the author’s main contributions are as follows:1. By electro-polymerization methods, four kinds of poly (sulfonic azo dye) modified electrodes, including poly (new coccine)/CPE, poly (sunset yellow)/CPE, poly (zincon Sodium Salt)/CPE and poly(ponceau S)/CPE, were fabricated and their behaviors of electro-chemistry and electro-catalysis were investigated respectively. The spectral results and surface characteristics of modified CPE indicated the hydrazone functional groups in the poly (sulfonic azo dye) structure catalysed dopamine electro-chemical reaction, and sulfo functional groups could adsorb of dopamine to enhance the electrochemical properties of the modified electrodes.2. A facile electro-chemical sensor based on citrazinic acid (CA) functionalized graphene (CA-rGO) was fabricated. The composite film modified electrode exhibited excellent selectivity and sensitivity towards dopamine (DA) and uric acid (UA) detection, owing to the electro-catalytic effect of non-directional arrangement of rGO. Differential pulse voltammetry (DPV) was used to determine DA in the presence of UA. It was found that all of oxidation peaks of two species could be well resolved. The calibration curve for DA ranged from0.30to909μM with a detection limit of0.09μM (signal/noise=3). The constructed sensor has been employed to quantitatively determine DA and UA in real samples.3. Electro-chemical characterization of IDHP on poly (new coccine) was investigated by cyclic voltammetry and differential pulse voltammetry. This modified CPE exhibited excellent electro-catalytic activity towards the oxidations of IDHP. Well defined and separated oxidation peaks were observed by CV. Linear calibration plots for the oxidation of IDHP was obtained in the range of0.4x10-6~2xl0-5mol/L. Detection limits of IDHP was found to be1.0xlO-7mol/L. and next the interaction behaviour between IDHP and bovine serum album (BSA) was investigated by CV and DPV. The results indicated that IDHP could combine with BSA to generate non-electroactivity complexes, the binding number was2and the binding constant of1.00x1010L mol"1was obtained.更多还原