Influence of perfluorocarbons on protein adsorption at Langmuir films

We propose a combined grazing incidence X-ray diffraction and X-ray reflectivity study on the effect of aerolized and gaseous perfluorocarbons (a- and gFCs) to protein adsorption at Langmuir films using different proteins, surface pressures and gas pressures at beamline ID10 of the ESRF. Aim of the proposed experiment is the determination of the lateral and vertical structure of model membranes of lung surfactant lipids like anionic DPPA and zwitterionic DPPC before and after protein adsorption and the influence of an overlying FC atmosphere to the protein adsorption behaviour. The substances have been selected based on their biomedical research interest. Especially a- and gFCs with a high vapour pressure are in focus of research as they represent a new approach to replace liquid FC ventilation and the unsafe use of the animal LS replacements to treat LS injuries or deficiency in adults and neonatal children. The combination of XRR and GID gives a comprehensive picture of the system.

本研究拟结合掠入射X射线衍射（Grazing Incidence X-ray Diffraction, GID）与X射线反射率（X-ray Reflectivity, XRR）技术，在欧洲同步辐射光源（ESRF）的ID10光束线上开展实验，探究雾化全氟碳化物（a-FCs）与气态全氟碳化物（g-FCs）对朗缪尔膜表面蛋白质吸附行为的影响，实验中采用了不同种类的蛋白质、表面压力与气体压力参数。本实验的核心目标为：测定由肺表面活性物质（lung surfactant, LS）脂质（如阴离子型二棕榈酰磷脂酸（Dipalmitoylphosphatidic acid, DPPA）与两性离子型二棕榈酰磷脂酰胆碱（Dipalmitoylphosphatidylcholine, DPPC））构成的模型膜在蛋白质吸附前后的横向与纵向结构，同时探究上方覆盖的全氟碳化物气氛对蛋白质吸附行为的调控作用。本次实验选用的物质均基于其在生物医学领域的研究价值。其中，高蒸气压的a-FCs与g-FCs更是当前研究的重点方向：这类物质为替代液体全氟碳通气疗法提供了全新思路，同时可规避使用动物源肺表面活性物质替代物治疗成人及新生儿肺表面活性物质损伤或缺乏症时存在的安全隐患。XRR与GID技术的联用可全面表征该实验体系的结构与动态行为。