牛血清白蛋白与奎宁和奎尼丁的相互作用研究

The enantioselective interaction between bovine serum albumin and quinine/quinidine

牛血清白蛋白(BSA)自组装在经电沉积纳米金修饰的玻碳电极表面,构建了简单的电化学手性传感界面,并讨论了该界面与不同浓度范围的抗疟疾手性药物奎宁和奎尼丁的相互作用。实验采用扫描电子显微镜(SEM)和循环伏安技术(CV)研究了手性界面的表面形貌和电化学行为,并用差分脉冲伏安法(DPV)和紫外-可见分光光度法(UV-Vis)测试了BSA与奎宁、奎尼丁之间的选择性作用。实验结果表明,当奎宁和奎尼丁浓度小于5.0×10^(-4)mol/L时,手性界面与奎尼丁作用后获得较大的电流响应,而当奎宁和奎尼丁的浓度等于或大于5.0×10^(-4)mol/L时,手性界面与奎宁作用后获得较大的电流响应;这是由于较大浓度时,奎宁和奎尼丁会破坏BSA的内部氢键、暴露疏水腔,使BSA以一种更疏松的状态存在,有利于电子传递。

A simple chiral sensing platform for enantioselective recognition of the anti-malaria chiral drug of quinine（QN） and quinidine（QD） was fabricated via the self-assembled of bovine serum albumin（BSA） on the electrodepositive gold nanoparticles（Au NPs） modified glassy carbon electrode. The sensing platform was characterized with scanning electron microscope（SEM） and cyclic voltammetry（CV）. Differential pulse voltammetry（DPV） and Ultraviolet-visible spectroscopy（UV-Vis） were used to study the enantioselective interaction between QN/QD and bovine serum albumin. The results displayed that after the self-assembled interface interacting with QN and QD, a larger electrochemical signal was achieved from QD when the concentration of QN and QD less than 5.0×10^-4mol/L, however, a larger singal was obtained from QN when the concentration of QN and QD increased to 5.0×10^-4mol/L due to QN and QD damaged the intraprotein hydrogen bonds of BSA which make BSA unfold and compelled the protein adopt a more imcompact conformation state which enhanced the electron transfer rate.