荧光猝灭法研究马钱子碱、士的宁与人血清白蛋白的相互作用

Interactions between brucine,strychnine and human serum albumin by using fluorescence quenching method

目的研究马钱子碱、士的宁与人血清白蛋白(HSA)间非共价结合特性。方法采用荧光猝灭法计算药物与蛋白间的结合常数与结合位点数;根据不同作用温度时药物-蛋白非共价结合复合物的热力学参数变化,分析药物与蛋白间的主要作用力类型。结果当作用温度分别为25℃和35℃时,马钱子碱与HSA的结合常数(K)分别为2.12×104L/mol和1.97×104L/mol,结合位点数(n)分别为1.07和1.07;士的宁与HSA的K分别为6.34×103L/mol和3.05×103L/mol,n分别为1.01、0.97。马钱子碱、士的宁与HSA间的作用力主要为氢键和范德华力。结论马钱子碱、士的宁与HSA能自发形成不发荧光的复合物,这种药物蛋白结合可能对马钱子碱、士的宁的药动学过程产生一定影响。

Objective To investigate the effects of both brucine and strychnine on human serum albumin（HSA）.Methods The binding constant K and the binding sites value（n） between drug and protein were gotten by fluorescence quenching method： and depending on the changes of thermodynamic parameters about the drug-protein complex under different temperatures,the main binding forces could be obtained between these two medicines and HSA.Results When the temperatures were 25 ℃ and 35 ℃,the binding constant K between brucine and HSA were 2.12×10^4 and 1.97×10^4 L/mol with the binding sites value（n） of 1.07 and 1.07,respectively.To strychnine and HSA,the binding constant K at different temperatures were 6.34×10^3 and 3.05×10^3 L/mol.The n were 1.01 and 0.97.Conclusion Brucine,strychnine and HSA can be combined compound which have no fluorescence,and the drug-protein binding may have some impact on the pharmacokinetics of brucine and strychnine.