金丝桃素和β-环糊精结合常数的测定

摘要

The inclusion complex and the binding constants between hypericin and β-cyclodextrin are determined by Microscale Thermophoresis and Molecular Fluorescence Spectrometry,and the experimental data were fitted by Hill equation. It is known that β-cyclodextrin can include Hypericum to some extent. Using these two approaches to test respectively, in the inclusion complex molecule,the ratios of hypericin andβ-cyclodextrin are respectively 1:5 and 1:7, with the microscopic dissociation constants KA of 1.82ng·L-1 and 3.72ng·L-1 as well as the equilibrium dissociation constants Kd of 76.92 and 1120.23. The relatively reliable results can be acquired rapidly by the methods.%采用微量热泳动法和分子荧光光谱法分别测定金丝桃素与β-环糊精的包合物和结合常数，并对实验数据进行Hill拟合.实验表明：β-环糊精对金丝桃素有一定程度的包合.两种方法测得的金丝桃素和β-环糊精包合物中金丝桃素、β-环糊精的分子个数比分别为1：5和1：7，微观解离常数KA分别为1.82ng·L-1和3.72ng·L-1，平衡解离常数Kd分别为76.92和1120.23.该方法快速、简便、试验结果相对可靠.