目的:采用荧光光谱技术研究羟基喜树碱与牛血清白蛋白(BSA)的相互作用。方法:根据292 K和311 K时羟基喜树碱对BSA的荧光猝灭作用,利用Stern-Volmer方程,双倒数方程以及F?rster非辐射能量转移理论处理实验数据,采用同步荧光光谱探讨了羟基喜树碱对BSA构象的影响。结果:羟基喜树碱与BSA间的结合距离r=3.08 nm(292 K),结合常数(Kb)为1.260×106 L·mol-1(292 K)和3.881×104 L·mol-1(311 K),羟基喜树碱与BSA结合的热力学参数△rHm〉0,△rSm〉0,△rGm〈0。结论:羟基喜树碱对BSA的荧光猝灭作用属于静态猝灭,二者主要靠疏水作用力结合。
Objective:To study the interaction of bovine serum albumin(BSA) with anticancer drug hydroxycamptothecin(HCPT) by fluorescence quenching spectra and synchronous fluorescence spectra.Methods:The Stern-Volmer curve and double logarithm equation and F?rster theory of non-radiation energy transfer was used to deal with the dates of fluorescence quench,and the synchronous spectrum was used to investigate the conformational changes of BSA.Results: The binding distances(r) of hydroxycamptothecin to BSA was 3.08 nm(292 K);the binding constants(Kb) were 1.260×106 L·mol-1(292 K) and 3.881×104 L·mol-1(311 K),respectively.The thermodynamic parameters △rHm〉0,△rSm〉0 and △rGm〈0. Conclusion:The static quenching exits between BSA and anticancer drug hydroxycamptothecin super-molecular complex,and interaction of them is mainly driven by hydrophobic force.