Novel Electro-generated Chemiluminescence Reaction at Boron-doped Diamond Electrode and Application for Selective Detection of Bio-related Compounds

本研究的目的是探索硼掺杂金刚石（BDD）表面的新型电化学发光（ECL）反应，并利用新型ECL反应在BDD电极上实现新的分析系统，特别是用于医学用途。硼掺杂金刚石表面新型ECL反应的探索。在掺硼金刚石电极上的[Ru(bpy)_3]^<2+>的ECL体系中，在抗坏血酸作为共反应物分子存在下，在约3.5 V vs. Ag/AgCl的极高电位区观察到强ECL发射。ECL反应的峰电位与共反应物浓度呈线性关系，ECL强度与共反应物OH自由基吸氢速率呈正相关。因此，澄清了在极高电位区发生的ECL反应包括出水时BDD表面OH自由基生成的共反应物自由基形成过程。通过应用这种新的ECL反应进行电化学分析，可以选择性地检测容易与OH自由基形成还原自由基的化合物（如2-丙醇或四氢呋喃）。[Ru(bpy)_3]^<2+>的ECL系统是一种能够通过控制样品的pH值来选择性地检测尿液中的草酸（包括许多电化学活性化合物）的分析方法。为了实现能够检测草酸的光化电极材料，研究了在高密度、高耐久性的金刚石表面直接改性[Ru(bpy)_3]^<2+>的方法。作为修饰方法，我们选择了金刚石表面碳原子与旁吡啶图例中引入的十二烷基端形成C-C键的方法。将改良的BDD电极安装在高效液相色谱系统的ECL检测器中，对真实尿液进行分析。仅对真实尿液中的草酸有ECL发射，HPLC和FIA的ECL强度在同一范围内，表明该修饰的BDD电极可选择性检测真实尿液中的草酸，灵敏度高（S/N= 3.5 μm）。此外，在3小时的连续分析中，这种修饰电极没有显示ECL强度的退化。因此，我们可以成功地制造出具有高耐久性的光功能化电极材料，用于选择性检测真实尿液中的草酸。少

The objective of this study is to explore the novel electro-generated chemi-luminescence (ECL) reaction at the boron-doped diamond (BDD) surface and to realize the new analyzing system, especially for medical purpose, using the novel ECL reaction at BDD electrodes.[1]The exploration of the novel ECL reaction at boron-doped diamond surface.For the ECL system of [Ru(bpy)_3]^<2+> at the boron-doped diamond electrodes, the strong ECL emission was observed in the extremely higher potential regions of approximately 3.5 V vs. Ag/AgCl in the presence of ascorbic acid as a co-reactant molecule. The peak potentials of this ECL reaction show the linear relation with the concentration of the co-reactant, and the ECL intensities were correlated with the rates for hydrogen abstraction reaction by OH radicals from the co-reactant. Therefore, it was clarified that the ECL reaction in the extremely higher potential region includes the process of the co-reactant radical formation by OH radicals generate … More d at the BDD surface during water discharge.By applying this novel ECL reaction for the electrochemical analysis, it is possible to selectively detect the compounds that easily form the reducing radicals with OH radicals (e.g.2-propanol or tetrahydrofuran).[2]The development of the diamond ECL sensor for medical application 〜 Analysis System for oxalic acid in urineThe ECL system using [Ru(bpy)_3]^<2+> was the analytical method that enable to selectively detect oxalic acid in urine including numerous electrochemically active compounds by controlling the pH value of the sample. In order to realize the photo-fictionalized electrode material that enable oxalic acid detection, the development of the method of the direct modification of [Ru(bpy)_3]^<2+> on the diamond surface with high density and high durability was carried out. As the modification method, it was selected the methods to form C-C bonding between carbon atoms on diamond surface and terminus of dodecyl groups introduced in the bypyridil legend. Modified BDD electrode was installed into the ECL detector in HPLC system, and the real urine was analyzed. ECL emission was obtained only for oxalic acid in real urine, and ECL intensity for HPLC and that for FIA were in the same range, indicating that this modified BDD electrode can selectively detect oxalic acid in real urine with high sensitivity (S/N=3,5μm). Moreover, this modified electrode did not show the degradation of ECL intensities during continuous analysis over 3 hours. Therefore, we could successfully fabricate the photo-functionalized electrode materials for the selective detection of oxalic acid in real urine with high durability. Less