摘要
电化学发光(electrochemiluminescence, ECL),又称为电致化学发光,是指通过施加一定的电压进行电化学反应,在电极表面产生一些电生的物质,然后这些物质之间或电生物质与体系中的某些组分之间通过电子传递形成激发态,由激发态返回到基态而产生的一种发光现象。电化学发光物质三吡啶钌(Ru(bpy)32+)由于性能优越,如何将其有效的固定在电极表面是研究的一个热点。目前,基于Ru(bpy)32+的各种电化学发光传感器,主要集中在免疫分析、PCR分析、DNA单分子检测、药物分析等领域。钛酸盐纳米管作为载体的电化学传感器的研制还比较少,电化学发光传感器用于环境方面的应用研究还比较缺乏,因此加强这方面的工作十分必要。本论文结合近年来关于钛酸盐的研究成果,开展了钛酸盐纳米管及其Ru(bpy)32+复合材料的合成,利用合成的功能材料制备了电化学传感器,获得了一些创新性研究成果。
本文采用水热法制备了二氧化钛纳米管(TNTs),其管径小、管壁薄、比表面积大、因此拥有很多优良的性能。在此基础上,我们进一步合成了Ru(bpy)32+-TNTs的纳米复合材料,并用透射电镜(TEM)、紫外可见光谱(UV-vis)、XPS等进行了表征。将合成的复合材料分散到Nafion溶液中,采用滴涂法修饰到电极上制备成电化学传感器,并对传感器的电化学性能运用循环伏安法进行了研究,同时利用电化学发光检测装置记录了光电信号。并与传统的层层自组装法制备的传感器进行了比较。结果表明分散在Nafion中的纳米复合体的滴涂法能更为有效的固定电化学发光物质Ru(bpy)32+,传感器对三丙胺(TPA)的检测结果也证明了该传感器的稳定性。最后,我们将该传感器用于环境分析领域,探讨了利用电化学发光法测定铅离子的原理与方法,为今后更为广泛的应用研究打下了基础。
Electrogenerated Chemiluminescence, is also called Electrochemiluminescence. It is a sort of electrochemical reactions which will product some electric materials on the surface of the electrode by supplying certain voltages. The generated electric materials turn to the state of excitation through the electron-transfer when it has reaction with the components of system. There will be a chemiluminescence phenomenon when the material returns to be the ground state from the excited state. In recent years, the immobilization of Ru(bpy)32+ has to be a hot research area due to its excellent performance in the electrochemiluminescence (ECL). At present, most of the ECL sensors mainly focus on the areas of the immunoassay, PCR analysis, single molecules detection of DNA, pharmaceutical analysis and so on. The studies of ECL sensor based on titanate nanotubes (TNTs) have rarely been reported especially in the application research of environmental field. In view of this situation, it is very necessary for us to work hard in this area. In this paper, We synthesized the nano composites of Ru(bpy)32+ based on TNTs combined with the method of high speed centrifugation. Based on the synthesized nano composites of Ru(bpy)32+/TNTs, a novel ECL sensor has been constructed through modification of nano composites on a GCE. In the following experiments, we have obtained some useful results by means of the new ECL sensor.
In this paper, TNTs produced by alkali hydrothermal treatment, are one of the most promising materials in various fields for the unique combination of physico-chemical properties, such as large surface area, particular ion exchange, high sedimentation rate and tubular structure. We synthesized the Ru(bpy)32+/TNTs nanocomposites and got its characterizations by transmission electron microscopy (TEM), UV-vis absorbance spectra and XPS analysis. The Ru(bpy)32+/TNTs nanocomposites were sonicated in the solution of Nafion. Subsequently, the dispersion was dipped on the surface of the GCE to fabricate the ECL sensor. The performance of the ECL sensor was detected by tripropylamine (TPA) through the CV scan and ECL detection. The results show that the fabricated ECL sensor is very stable in this method. At last, we take this ECL sensor into the application of the area of environmental analysis. The ECL mechanism of Ru(bpy)32+ and EDTA was discussed and inhibiting effect of Pb(II) to this ECL system was investigated. Meanwhile the analytical method of Pb(II) by ECL was proposed and it laid a solid foundation for its further application.
引文
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