石英晶体微天平实时监测亲和素对低密度脂蛋白的吸附

Real-time in situ study of adsorption of low density lipoprotein onto surface of Avidin using quartz crystal microbalance

利用石英晶体微天平(QCM)实时监测低密度脂蛋白(LDL)在亲和素(Avid in)上的吸附,并探讨二者的作用机理。实验结果表明:Avid in与LDL之间的相互作用方式主要是静电吸附,即中性环境下带正电的Avid in可与LDL分子表面的带负电的磷脂分子发生静电吸引,当LDL浓度为0.049 5 g/L时,最大吸附量达到3.54×10-7g/cm2,吸附率为59.68%,NaC l溶液的洗脱效果达到了86%。研究证实:Avid in具有较大的吸附量和较高的吸附率,有望作为新型吸附LDL的吸附剂配基。

The use of quartz crystal microbalance （QCM） for monitoring in situ adsorption of low density lipoprotein （LDL） onto Avidin is described, and interaction mechanism is also discussed. Experimental results show that the binding of Avidin and LDL is electrostatic adsorption, because phospholipid with negatively charged at the surface of LDL had been found to mediate the interaction between LDL and Avidin under neutral condition. The maximal LDL adsorption capacity attains 3.54 × 10^ -7 g/cm^2 and the adsorptive efficiency calculated 59.68 % when LDL concentration is 0. 049 5 g/L. NaCl solution elution effect attains 86 %. In a word, a new method to evaluate the adsorption behavior is provided and Avidin is seen to be a potential lagand for LDL sorbent.