Engineering Research Equipment Grant: Advanced Laser Fluorescence for Interfacial Mass Transfer Studies

在这个研究设备项目中，一种先进的激光器 将开发一种荧光仪器来确定表面 或荧光标记的 空气/水和油/水单分子膜探针 接口。 这种改进的装置是基于一个简单的莫尔 使用荧光测量表面扩散的技术 光漂白后的恢复（FRAP），其中膜被漂白 以周期性的模式。 这种改进的FRAP技术将避免 与放射性示踪剂技术相关的许多问题 用于测量表面扩散。 这项新的实验技术 还将允许将研究表面扩散扩展到 以前无法研究的界面系统 放射性示踪法 此外，还可以将 在流动和扩散输运过程之间， 单分子膜 周期性图案增加了空间 分辨率相对于传统的单点FRAP 技术，导致更准确的扩散常数 决心。 该仪器将用于继续先前的地面工作 扩散在单分子膜，特别是，以确定 表面扩散系数的可靠值及其 表面浓度和温度依赖性 单分子层状态，以阐明性质的两个- 流体/流体界面处的三维质量传递。 激光 荧光仪器也将用于其他研究 项目包括单层结构，L-B膜，双层，和 固/液界面

In this Research Equipment project, an advanced laser fluorescence apparatus will be developed to determine the surface or translational diffusion coefficients of fluorescent-labeled probes in monomolecular films at air/water and oil/water interfaces. This improved apparatus is based on a simple Moire technique for measuring surface diffusion using fluorescence recovery after photobleaching (FRAP) where the film is bleached in a periodic pattern. This improved FRAP technique will avoid many of the problems associated with the radiotracer technique for measuring surface diffusion. This new experimental technique also will permit one to extend the study surface diffusion to interfacial systems previously inaccessible to study by the radiotracer method. In addition, one will be able to separate between flow and diffusional transport processes occurring in monomolecular films. The periodic pattern increases the spatial resolution relative to the conventional single spot FRAP technique, resulting in more accurate diffusion constant determinations. This apparatus will be used to continue previous work on surface diffusion in monomolecular films, in particular, to determine reliable values of the surface diffusion coefficient and its surface concentration and temperature dependence within various monolayer states in order to elucidate the nature of two- dimensional mass transfer at fluid/fluid interfaces. The laser fluorescence apparatus also will be used in other research projects including monolayer structure, L-B films, bilayers, and solid/liquid interfaces.