毛细管区带电泳测定两种生物碱与牛血清白蛋白的结合常数研究

Determination of the binding constants of two alkaloid compounds with bovine serum albumin by capillary zone electrophoresis

采用毛细管电泳淌度移动法研究盐酸麻黄碱、磷酸可待因与牛血清白蛋白(BSA)的结合常数.使用未涂层弹性石英毛细管柱75μm×60cm(有效长度50cm),在pH 7.40、浓度25mmol/L Tris-HCl的电泳缓冲溶液及分离电压20kV,紫外检测波长214nm,温度37℃的条件下,测得盐酸麻黄碱、磷酸可待因与BSA的结合常数分别为1.46×104 L/mol和0.75×104 L/mol.该法简单、快捷,可用于研究结合比为1∶1的药物小分子与生物大分子的相互作用.

The binding constants between two alkaloid compounds （ephedrine hydrochloride and codeine phosphate） and bovine serum albumin （BSA） were determined by capillary zone electrophoresis （CZE） on the basis of mobility shift method. The optimal conditions were. an uncoated fused-silica capillary （75 μm×60 cm）, the detection wavelength of 214 nm, applied voltage of 20 kV and temperature of 37 ℃. 25 mmol/L Tris-HC1 （pH=7.40） was selected for the running buffer. Under the optimum conditions, the binding constants （Kb） of these two alkaloid compounds were 1.46×10^4, 0. 75×10^4 L/mol for ephedrine hydrochloride and codeine phosphate, respectively. It was easy and simple to estimate the interaction of small molecule drugs with biomacromolecules with 1 ： 1 molar binding ratio.