RUI: New Devices and Methods for Microscale Spectroelectrochemistry

在这个由化学部化学测量成像计划资助的项目中，位于彭布罗克的北卡罗来纳州大学化学物理系的Paul Flowers教授正在开发用于非常小样品的化学分析的新设备和协议。这项研究为微尺度化学分析创造了新的工具和方法，相对于现有的可比技术，这些工具和方法在分析时间、成本和样本量要求方面具有优势。该项目雇用的本科生助理从不同的人口，是16%的美国印第安人和33%的非洲裔美国人，从事民族和种族群体，目前在国家的科学劳动力代表性不足的学生数量可观。与研究直接相关的课程实验室活动正在开发中，并纳入现有的化学课程在大二和高年级，显着扩大该项目的教育影响。光谱电化学（SEC）是指光谱和电化学技术的同时应用，通常涉及进行电解样品的光谱测量。自20世纪60年代SEC首次报道以来，这些技术已成为表征化学物质的氧化还原性质和阐明电极过程机制的成熟工具。最近和不断增长的努力是针对使用SEC作为定量化学分析的基础，基本上用惰性的非消耗性电极代替常规测定中使用的化学试剂。弗劳尔斯教授的小组以前开发了一种原型设备，允许SEC分析远低于1微升的样品体积，比任何其他报道的设备大约小两个数量级。在这个项目中，这个原型的基本设计正在进行调整，以允许微升和亚微升样品的流动分析。使用简单的聚合物浇铸技术来制造这些流动池，并使用伏安法、库仑法、计时吸收法和电压吸收法来评估其性能。在平行的设备制造工作，利用SEC测量策略的微尺度测定正在开发选定的生物和生物医学相关的化合物。

In this project funded by the Chemical Measurement & Imaging Program of the Chemistry Division, Professor Paul Flowers of the Department of Chemistry & Physics at the University of North Carolina at Pembroke is developing new devices and protocols for the chemical analysis of very small samples. This research creates new tools and methodology for microscale chemical analysis that offer advantages in analysis time, cost and sample size requirement relative to comparable existing techniques. The project employs undergraduate assistants selected from a diverse population that is 16% American Indian and 33% African American, engaging significant numbers of students in ethnic and racial groups that are presently underrepresented in the nation's scientific workforce. Curricular laboratory activities directly related to the research are being developed and integrated into existing chemistry courses at the sophomore and senior levels, significantly broadening the educational impact of the project.Spectroelectrochemistry (SEC) refers to the simultaneous application of spectroscopic and electrochemical techniques and typically involves making spectral measurements on samples undergoing electrolysis. Since the first reports of SEC in the 1960s, these techniques have become well-established tools for characterizing the redox properties of chemical species and elucidating the mechanisms of electrode processes. A more recent and growing effort is directed towards the use of SEC as the basis for quantitative chemical analyses, essentially replacing the chemical reagents used in conventional assays with an inert, nonexpendable electrode. Professor Flowers'group has previously developed a prototype device that permits SEC analysis of sample volumes well below one microliter, roughly two-orders of magnitude lesser than any other reported device. In this project, the basic design of this prototype is being adapted to permit flow analyses of microliter and sub-microliter samples. Simple polymer casting techniques are being utilized to fabricate these flow cells, and their performance is being evaluated using voltammetry, coulometry, chronoabsorptometry and voltabsorptometry. In parallel to the device fabrication work, microscale assays that exploit SEC measurement strategies are being developed for selected compounds of biological and biomedical relevance.