Study on Atomically Ordered Surfaces of Functional Electrodes for Electron Transfer Reactions of Metalloproteins

本研究利用金单晶电极表面研究了修饰电极对金属蛋白电子转移反应的表面功能.单晶电极表面的制备与表征：采用真空蒸发法和火焰退火淬火法制备了金单晶电极表面，并利用STM/AFM和电化学测试对不同制备条件下的金单晶电极表面进行了表征.用于金属蛋白电子转移反应的功能电极表面：（1）利用扫描隧道显微镜（STM）、表面增强红外吸收光谱（SEIRAS）和电化学还原脱附技术研究了修饰Au单晶电极的表面结构。例如，在Au（111）表面上，吸附的4-吡啶巯基（4-PySH）表现出p（5* 3R-<square root>3 O-）结构的矩形晶胞，其中两个相邻的4-PySH相互作用，而2-PySH则表现出p（5* 3R-3 O-）结构的矩形晶胞，其中两个相邻的4-PySH相互作用，而2-PySH则表现出p（5 * 3R-3 O-）结构的矩形晶胞。 ...更多信息 -PySH修饰电极显示p（4* <square root>7 R-40.9 π）结构，没有二聚体形成，表明2-PySH吸附在硫醇盐S和吡啶N原子上。(2)利用In 2 O3电极的高亲水性sin-face，发现天然和重组肌红蛋白的生物学功能和电子传递动力学与血红素的结构密切相关，如血红素的卟啉骨架、氧化还原中心的金属离子类型、配位结构等.在单晶金电极表面用硫醇修饰：非常少量（约100%）。发现硫醇改性剂溶液中的硫化物杂质在某些情况下使改性的表面结构复杂化。然而，改性表面的结构在很大程度上受改性过程的热力学和动力学方面的控制。吸附在电极表面的硫醇的还原脱附峰电位被发现是一个很好的措施，用于预测修饰表面的结构。硫醇改性表面的电化学制造也得到了发展。少

In the present study, surface functions of modified electrodes for electron transfer reactions of metalloproteins have been examined by using gold single crystal electrode surfaces.1. Preparation and characterization of single crystal electrode surfaces :Gold single cryatal surfaces were prepared by both vacuum evaporation and flame-annealing-quenching methods, and their surfaces were characterized by STM/AFM and electrochemical measurements as a function of preparation conditions.2. Functional electrode surfaces for electron transfer reactions of metalloproteins :(1) Surface structures of modified Au single crystal electrodes for cytochrome c electrochemistry were studied by STM, surface-enhanced IR absorption spectroscopy (SEIRAS) and the electrochemical reductive desorption technique. On the Au(1 11) surface, for example, adsorbed 4-pyridinethiol (4-PySH) showed the rectangular unit cell of p(5*<square root>3R-3Oﾟ) structure with an interaction of two neighboring 4-PySH, while the 2 … More -PySH modified electrode showed a p(4*<square root>7R-4O.9ﾟ) structure with no dimer formation, suggesting that 2-PySH adsorbs at both thiolate S and pyridine N atoms.(2) Using highly hydrophilic sin-face of In203 electrodes, biological functions and electron transfer kinetics of native and reconstituted myoglobins were found to be related very much to the heme structure, such as the porphyrin backbone of the heme, type of metal ion of the redox center, coordination structure etc.3. Modification with thiols on single crystal gold electrode surfaces :A very small amount (ca. 1%) of sulfide impurity in a thiol modifier solution was found to make the modified surface structure complicated in some cases. However, the structure of modified surface was very much controlled by thermodynamic and kinetic aspects of the modification processes. The reductive desorption peak potentials of thiols adsorbed on the electrode surfaces were found to be used as an excellent measure for predicting the structures of the modified surfaces. Electrochemical fabrication for the thiol modified surface has also developed. Less