Lee Youngmi, Ding Zhifeng, Bard Allen J
Department of Chemistry and Biochemistry, University of Texas at Austin, 78712, USA.
Anal Chem. 2002 Aug 1;74(15):3634-43. doi: 10.1021/ac015713u.
A technique that combines scanning electrochemical microscopy (SECM) and scanning optical microscopy (OM) was developed. Simultaneous scanning electrochemical/optical microscopy (SECM/OM) was performed by a special probe tip, which consists of an optical fiber core for light passage, surrounded by a gold ring electrode, and an outermost electrophoretic insulating sheath, with the tip attached to a tuning fork. To regulate the tip-substrate distance, either the shear force or the SECM tip current was employed as the feedback signal. The application of a quartz crystal tuning fork (32.768 kHz) for sensing shear force allowed simultaneous topographic, along with SECM and optical imaging in a constant-force mode. The capability of this technique was confirmed by obtaining simultaneously, for the first time, topographic, electrochemical, and optical images of an interdigitated array electrode. Current feedback from SECM also provided simultaneous electrochemical and optical images of relatively soft samples, such as a polycarbonate membrane filter and living diatoms in a constant-current mode. This mode should be useful in mapping the biochemical activity of a living cell.
开发了一种将扫描电化学显微镜（SECM）和扫描光学显微镜（OM）相结合的技术。通过一种特殊的探针尖端进行同步扫描电化学/光学显微镜（SECM/OM）操作，该探针尖端由用于光传输的光纤芯、被金环电极包围以及最外层的电泳绝缘鞘组成，且尖端连接到一个音叉上。为了调节尖端与基底的距离，可采用剪切力或SECM尖端电流作为反馈信号。使用石英晶体音叉（32.768 kHz）来感测剪切力，能够在恒力模式下同时进行形貌以及SECM和光学成像。通过首次同时获取叉指阵列电极的形貌、电化学和光学图像，证实了该技术的能力。来自SECM的电流反馈还能在恒流模式下提供相对柔软样品（如聚碳酸酯膜过滤器和活硅藻）的同步电化学和光学图像。这种模式在绘制活细胞的生化活性图谱方面应该会很有用。
