原位椭圆偏振术研究牛血清清蛋白在固/液界面的吸附

ADSORPTION OF BOVINE SERUM ALBVMIN AT THE SOLID/LIQUID INTERFACE QUANTITATED BY IN SITU ELLIPSOMETRY

用原位椭圆偏振术系统研究了硅片表面因素及缓冲液环境因素对牛血清清蛋白在固/液界面吸附的影响。在生理条件下,疏水表面与亲水表面相比BSA吸附量较大。随着硅片表面电荷密度增加,BSA吸附量增加。BSA吸附量当体溶液pH值等于BSA等电点时达到最大。而随着体溶液离子强度增加,BSA吸附量亦上升。实验结果提示:除了熵驱动作用之外,硅片表面与BSA分子及BSA分子之间的静电作用在BSA吸附中起着十分重要的作用。

The effects of different silica surfaces and different bulk solutions on the adsorption of BSA at the solid/liquid interface were systematically studied by in situ ellipsometry. The BSA amount adsorbed on the hydrophobia silica surface was larger than that on the hydrophilic silica surface at physiological pH. As the surface charge density increased, the adsorbed BSA amount also increased. It reached maximum at the isoelectric point of BSA. The BSA adsorbed amount increased as ionic strength in bulk solution increased. It is very likely that the electrostatic interactions between silica surface and BSA play an important role in the BSA adsorption.