Photofunctional Characteristics at Interfaces

在光学显微镜下，聚焦的1064 nm激光照射丁醇水溶液，通过光热相分离形成单个丁醇微滴。同时，利用1064 nm激光可以在太空中操纵生成的丁醇微滴，并用荧光/拉曼光谱对其进行研究。这项特殊的技术还成功地与微芯片以及毛细管电泳法相结合。在这一新技术的基础上，通过激光照射，可以将丁醇水溶液中超微量的分析物提取到单个皮升丁醇液滴中，并基于荧光显微光谱对分析物的液/液萃取过程进行了详细的研究。特别是在使用微芯片的情况下，已经通过激光束实现了分析物到单个液滴的连续和自动的液/液萃取。更进一步的…此外，采用毛细管电泳法对样品进行了提取和分析，为微分析化学提供了一种新的技术手段。另一方面，二茂铁端基烷硫醇自组装单分子膜(SAM)修饰的金电极已被成功地集成到聚合物微通道芯片中。基于SAM中二茂铁基的氧化还原反应，证明了溶液在微通道中的电化学流动控制。通过接触角测量和表面增强红外吸收光谱分析，阐明了微通道芯片中电化学流动控制的基本机理。研究表明，在SAM中二茂铁基的电化学氧化过程中，高氯酸盐阴离子作为二茂铁阳离子的反离子同时吸附在SAM表面，并伴随着水分子在SAM表面的吸附，从而增加了SAM/电极表面的润湿性。当二茂铁基被还原时，高氯酸根离子和水分子分布到水相。通过对高氯酸根离子和水分子的吸附/脱附，可以用电化学方法控制表面润湿性。较少

Irradiation of a focused 1064 nm laser beam to an aqueous butanol solution under an optical microscope gives rise to formation of a single butanol microdroplet through photo-thermal phase separation of the solution. Simultaneously, the butanol microdroplet produced can be manipulated in space by the 1064 nm laser beam and studied by fluorescence/Raman microspectroscopies. The particular technique was also combined successfully with a microchip as well as with a capillary electrophoresis. On the basis of such a new developed technique, an ultra-race amount of an analyte in an aqueous butanol solution can be extracted into a single picoliter butanol droplet by laser irradiation and the liquid/liquid extraction processes of the analyte have been studied in detail on the basis of fluorescence microspectroscopy. In the case of the use of a microchip, in particular, consecutive and automatic liquid/liquid extraction of an analyte into a single droplet has been achieved by a laser beam. Furth … More ermore, the analyte separated by a capillary electrophoresis has been extracted and analyzed by the present methodology, which has high potential as a novel technique for microanalytical chemistry.On the other hand, gold electrodes modified with a ferrocene-terminated alkanethiol self-assembled monolayer (SAM) have been successfully integrated into a polymer microchannel chip. On the basis of oxidation-reduction reactions of the ferrocenyl groups in the SAM, electrochemical flow control of the solution in a microchannel has been demonstrated. The fundamental mechanisms of the electrochemical flow control in the microchannel chip have been also elucidated on the basis of contact angle measurements and surface-enhanced infrared absorption spectroscopy. The study has demonstrated that a perchlorate anion as a counter ion of the ferrocenium cation adsorbed simultaneously onto the SAM surface upon the electrochemical oxidation of the ferrocenyl group in the SAM and this accompanies adsorption of water molecules on the SAM surface, giving rise to the increase in the wettability of the SAM/electrode surface. Upon reduction of the ferrocenyl group, a perchlorate ion and water molecules distribute to the water phase. Through adsorption/desorption of a perchlorate ion and water molecule, the surface wettability can be controlled electrochemically. Less