丹酚酸B与牛血清白蛋白相互作用的电化学研究

Investigation on Electrochemical Behavior of Interaction between Salvianolic Acid B and Bovine Serum Albumin at DNA Modified Electrode

在0.01 mol.L-1磷酸盐缓冲溶液(pH 7.4)中,用循环伏安法和方波伏安法研究了丹酚酸B与牛血清白蛋白相互作用前后在DNA修饰玻碳电极上的电化学行为。实验表明,丹酚酸B在此修饰电极上于0.100 V处产生良好的氧化峰,加入牛血清白蛋白后,丹酚酸B的电子转移系数α和表观电子传递速率常数ks均发生了变化,氧化峰电位正移,峰电流减小。根据氧化电流的变化求得丹酚酸B和牛血清白蛋白相互作用的结合常数β=1.00×108L.mol-1,结合数m=1.71,表明丹酚酸B与牛血清白蛋白生成了结合比约为2∶1的非电活性复合物。该结果与荧光光谱法的研究结果一致。

The electrochemical behavior of interaction between salvianolic acid B （SalB） and bovine serum album in（BSA） was investigated by cyclic voltammetry and square wave vohammetry based on DNA-modified glass carbon electrode （GCE） in 0. 01 mol/L phosphate buffer solution （pH 7.4 ）. SalB generated a sensitive oxidation peak of 0. 100 V at the DNA-modified GCE. After addition of BSA into the SalB solution, the oxidation current decreased and the peak potential shifted positively. The electrochemical parameters, such as the charge-transfer coefficient α and the standard electron- transfer rate constant ks were also changed. The binding number rn of 1.71 and the binding constant β of 1.00 x 108 L/mol were calculated according to the data of the oxidation current, which indicated that SalB could combine with BSA to generate a non-electric complexes with combination ratio of 2 ： 1. The results were in agreement with that provided by the fluorescence spectrometric method.