Applications of Novel Scanning Probe Methods to Electrochemical Studies.

分析和表面化学计划支持德克萨斯大学奥斯汀分校的艾伦·巴德教授的这一项目，其中将开发几种新的扫描探针/电化学显微镜技术。首先，扫描电化学显微镜(SECM)将被应用于测量通过双层脂膜的单个通道的离子通量，然后是活细胞的离子通量。初步实验已经检测到碘通过细胞膜的运输，其他研究人员已经使用巴德教授的SECM方法来监测分子离子通过活细胞膜的运输。SECM有可能既作为一种成像设备，又作为一种定量工具来提取有关离子传输的动力学信息。一个潜在的应用领域是神经元微环境和胞吐过程中神经递质的释放。第二种仪器将SECM与电致化学发光相结合。以前的研究证明了这种潜力，但受到尖端大小和尖端-衬底间距的限制。新开发的探针将克服这些问题，并允许详细研究电极表面及其附近的电化学反应。其应用包括通过一种称为“分子伏安法”的方法对分子电子器件进行表征。在分子尺度的纳米结构中，电子电荷的离散性已经被证明对器件性能起着显著的作用，这些可以用所提出的分析方法来进一步研究。扫描探针显微镜被广泛地应用于表面的研究，包括从化学反应的电极表面到活细胞的表面。在这个项目中，将开发新的技术，目标是改善成像特征的量化。例如，离子通道已经在细胞膜上成像。下一个问题是：离子通过成像离子通道的传输速度是多少？

The Analytical and Surface Chemistry program supports this project by Professor Allen Bard of the University of Texas at Austin in which several new scanning probe/electrochemical microscopy techniques will be developed. First, scanning electrochemical microscopy (SECM) will be applied to the measurement of ion flux through a single channel of a bilayer lipid membrane, and then of living cells. Preliminary experiments have detected iodine transport across a membrane, and other researchers have used Prof. Bard's SECM method to monitor molecular ion transport through living cell membranes. There is the potential to use SECM both as an imaging device and as a quantitative tool to extract kinetic information about ion transport. A potential area of application is in the neuronal microenvironment and the release of neurotransmitters during exocytosis. A second instrument combines the SECM with electrogenerated chemiluminescence. Previous studies demonstrated the potential, but were limited by tip size and tip-substrate spacing. Newly developed probes will overcome these problems and permit detailed studies of electrochemical reactions at and near electrode surfaces. Applications include characterization of molecular electronic devices via a method termed "molecular voltammetry". In molecular scale nanostructures, the discreteness of the electronic charge has been demonstrated to play a prominent role in device performance, and these can be further studied with the proposed analytical methods.Scanning probe microscopy is widely used in the study of surfaces, including chemically reactive electrode surfaces to the surface of a living cell. In this project, new techniques will be developed with a goal toward improving the quantification of the imaged features. For example, ion channels have been imaged on cell membranes. The next question is: What is the rate of ion transport through the imaged ion channel?