IN-SITU INFRARED ANALYSIS OF BIOMEMBRANE MONOLAYERS

拟议研究的总体目标是开发和 应用外反射红外光谱作为 分析方法来观察，在现场，红外光谱的 气-水不溶性模型生物膜 接口. 而空气-水界面的生物膜单层 界面已被广泛用作膜模型 双层和界面现象，几乎没有 关于详细物理结构的现有信息 这些系统。 我们建议将红外光谱应用于 对这些薄膜的原位研究， 描述了它们的结构、动力学和界面性质。 本提案中描述的研究将是第一个 利用振动光谱直接测量 这些模型膜的分子水平物理结构 在空气-水界面。 研制了手动Langmuir-Blodgett薄膜天平， 连接到我们实验室的FT-IR光谱仪上。 我们 建议研究越来越复杂的生物物理表面 这部电影的实验设计。 具体来说，我们打算 进行了以下实验：（1）研究热力学 磷脂单层膜的相变，（2）表征 膜表面的界面化学作为表面- 活性剂与膜界面相互作用，（3）研究 蛋白质单层和脂质-蛋白质复合物 界面，以尝试测量诱导的构象变化， (4)研究肺表面活性剂单层作为天然， 生理相关单层。 K.M.W.教授科夫 纽芬兰圣约翰纪念大学同意 合作进行肺表面活性物质的研究 这些研究的结果应该为物理学提供新的线索。 各种广泛使用的生物膜模型的结构。

The overall objective of the proposed research is to develop and apply the use of external reflection infrared spectroscopy as an analytical method to observe, in-situ, the infrared spectra of insoluble model biomembrane monolayers at the air-water interface. While biomembrane monolayers at the air-water interface have been extensively used as models for membrane bilayers and interfacial phenomena, there is virtually no information available concerning the detailed physical structure of these systems. We propose to apply infrared spectroscopy to the in-situ study of these thin films in order to more precisely described their structure, dynamics, and interfacial properties. The research described in this proposal would be the first to utilize vibrational spectroscopy to directly measure the molecular-level physical structure of these model membrane films at the air-water interface. A manual langmuir-Blodgett film balance has been fabricated and interfaced to an FT-IR spectrometer in our laboratory. We propose to study increasingly more complex biophysical surface films with this experimental design. Specifically, we intend to perform the following experiments: (1) Study the thermodynamic phase transitions of phospholipid monolayer films, (2) characterize the interfacial chemistry of the membrane surface as surface- active agents interact with the membrane interface, (3) study protein monolayers and lipid-protein complexes at the air-water interface to try to measure-induced conformational changes, and (4) study monolayers of pulmonary lung surfactant as a natural, physiologically relevant monolayer. Professor K.M.W. Keough of Memorial University, St. John's Newfoundland, has agreed to collaborate on the lung surfactant studies. The results of these studies should shed new light on the physical structure of a variety of widely used biomembrane models.