Research Initiation Awards: Surface-Induced Conformational Changes in Protein Films

这个项目将试图通过原位椭偏测量法将表面诱导的吸附蛋白质构象变化的速度或程度与其平衡吸附质量联系起来。将评估α-乳清蛋白、β-乳球蛋白和kappa-酪蛋白在锗上的平衡等温线。然后，通过椭偏仪连续监测膜厚来量化时间对这些蛋白质所经历的构象变化的影响。现在众所周知，高分子量的蛋白质可以通过它们与表面的相互作用来破坏。破坏的程度似乎与时间有关。据推测，这种损伤是在蛋白质展开时发生的，使更多的表面与它们被吸引到的表面区域接触。这一现象对生物医学技术和生物技术的下游加工都很重要。如果蛋白质随着它与表面逐渐强烈的相互作用而展开，似乎有理由预计被吸附的蛋白质膜的表观厚度随着时间的推移而减小，损伤量与膜厚度相关。这个项目将检验这一假设，并导致对这一现象及其动力学的更好理解。

This project will attempt to relate the rate or extent of surface- induced conformational changes in adsorbed proteins to their equilibrium adsorbed mass by in situ ellipsometry. Equilibrium isotherms of alpha-lactalbumin, beta-lactoglobulin, and kappa-casein on germanium will be evaluated. Then, the influence of time on conformational changes experienced by these proteins will be quantified by continuously monitoring the film thickness by ellipsometry. It is now well known that high-molecular weight proteins can be damaged by their interactions with surfaces. The extent of damage seems to be time-dependent. It is hypothesized that this damage occurs as the protein unfolds to bring more of its surface into contact with regions of the surface to which they are attracted. This phenomenon is important to both biomedical technology and downstream processing in biotechnology. If the protein unfolds as it interacts progressively strongly with the surface, it seems reasonable to expect the apparent thickness of a film of adsorbed protein to decrease with time and for the amount of damage to correlate with the film thickness. This project will test that hypothesis and lead to a better understanding of the phenomenon and its dynamics.