Development of Non-contact and Non-destructive Optical Waveguide Spectroscopy and Their Application to Electrochemical Analysis of Proteins fixed on the Interface.

在本计画中，我们首次成功地利用非接触式光波导光谱法来分析吸附在不透明基底上的分子的可见光吸收。非接触式测量采用新开发的专用电池系统。波导和衬底之间的差距距离通过薄间隔物或微粒来控制。用该池系统获得了固定分子的清晰吸收光谱，其间隙小于400 nm。此外，已经用不透明电极检查了相同的实验，以分析分子或蛋白质在电极表面的电化学响应。有趣的是，基质表面的物理化学特性极大地影响了蛋白质的吸附，这很容易用这种技术检测。该方法还发现了以前从未分析过的慢电子转移反应。还进行了动态测量，这被证明是有效的工具，吸附分子的分析。

In this project, we firstly succeeded to analyze the visible absorption of molecules adsorbed on the opaque substrate with non-contact optical waveguide spectroscopy. Non-contact measurement was carried out with newly developed special cell systems. The gap distance between waveguide and substrate was controlled with either thin spacer or micro particles. Clear absorption spectra of the fixed molecules were obtained with this cell system with very small gap less than 400 nm. Further, the same experiments have been examined with opaque electrodes to analyze the electrochemical response of molecules or proteins at the electrode surface. It was interesting that the physicochemical characteristics of the substrate surface greatly affected the adsorption of proteins that was easily detected with this technique. Slow electron transfer reaction was also detected by this method that had never been analyzed previously. Dynamic measurement was also carried out which was revealed to be effective tools for the analysis of adsorbed molecules.