Analytical Microscopy Methods for Characterizing Lipid Vesicles and Bilayers

化学系的化学测量和成像(CMI)和生命过程化学(CLP)计划支持犹他大学的Joel M.Harris教授开发新的方法来表征脂泡及其双层膜的组成、结构和功能。光学捕获共聚焦拉曼显微镜正在发展，以探测单个脂泡的组成和结构，目的是更好地了解脂双层结构与其通透性之间的关系。这反过来可能提供对分子摄取和释放的控制，这影响了药物输送和痕量分析应用。正在开发荧光显微镜工具来探测固定在玻璃表面的单个脂泡，目的是评估内部pH和分子传输速率，这可以作为单分子事件来检测。这项工作还试图设计一种方法来测量小肽与支撑的脂双层的结合，以及膜结合多肽种群的定量测定及其结合和解离的动力学。这项研究将为新的理解脂膜的结构和功能以及影响它们的过程提供途径。这些膜是活细胞的重要组成部分，例如，对它们的了解对于成功开发膜活性药物产品至关重要。该研究为研究生和本科生提供光谱学、显微镜、胶体科学和生物化学方面的多学科培训。该项目通过参与课堂活动、为盐湖城地区服务的新科学中心捐款以及运送到犹他州农村地区的新巡回展览，影响了K-12教育和公众意识。

The Chemical Measurement and Imaging (CMI) and Chemistry of Life Processes (CLP) programs of the Division of Chemistry support Prof. Joel M. Harris of the University of Utah to develop new approaches to characterizing the composition, structure, and functioning of lipid vesicles and their bilayer membranes. Optical trapping confocal Raman microscopy is being developed to probe the composition and structure of individual lipid vesicles, with an aim to better understand the relationship between the structure of the lipid bilayer and its permeability. This in turn may provide control over molecular uptake and release, which impact drug delivery and trace analysis applications. Fluores¬cence microscopy tools are being developed to probe individual lipid vesicles immobilized on glass surfaces, with an aim of assessing internal pH and molecular transport rates, which can be detected as single-molecule events. The work also seeks to devise means to measure the affiliation of small peptides with supported lipid bilayers, and quantitative determina¬tion of membrane-bound peptide populations and their kinetics of binding and unbinding.This research will provide routes to new understanding of the structure and functioning of lipid membranes and the processes that affect them. These membranes are important components of living cells, and their understanding is critical, for example, to the successful development of membrane-active pharmaceutical products. The research provides multidisciplinary training of graduate and undergraduate students in spectro¬scopy, microscopy, colloid science, and biological chemistry. The project impacts K-12 education and public awareness through involvement in classrooms, contributions to a new science center serving the metropolitan Salt Lake City area, and new touring exhibits that are transported to rural districts of the State of Utah.