大黄素电化学性质的研究

Emodin:An electrochemical study

目的:研究了大黄素的电化学性质以及大黄素与牛血清白蛋白(BSA)相互作用的电化学行为。方法:采用循环伏安法和差分脉冲伏安法对大黄素进行电化学行为的研究,并在不同pH值下进行线形扫描实验;同时应用紫外-可见分光光度法对大黄素与牛血清白蛋白的结合情况进行了研究。结果:大黄素在-0.522V处出现一个明显的还原峰;大黄素与牛血清白蛋白结合生成了一种非电活性的超分子化合物,并对结合反应的机理进行了探讨。结论:大黄素的还原峰电流与扫描速率呈简单线性关系。大黄素与牛血清白蛋白结合形成非电活性的超分子化合物导致大黄素氧化还原峰电流降低,峰电位基本不变,峰电流的下降值同所加入的BSA浓度在一定范围内呈线性关系。

Objective：To investigate electrochemistry of emodin and an electrochemical behavior of the interaction of emodin with bovine serum albumin（BSA） .Methods：The linear sweep voltammetry was tested with various pH values.And an ultraviolet-visible spectrophotometry was used to investigate the interaction of emodin with bovine serum albumin（BSA）.Results：A reductive peak potential of emodin was in-0.522V.An electrochemically inactive supramolecular complex BSA-Emodin was formed.Conclusion：The peak current decreases along with the increase in the times of scan,and the linear relation was found between the peak current and scan rate.The potential of reductive peak is linear with the logarithm values of scan rate.With the addition of BSA into an emodin solution,both the reduction and oxidation currents decrease with minor changes in the peak potential.The electrochemical parameters,such as the charge-transfer coefficient α and the standard electron-transfer rate constant ks in the absence and presence of BSA,were estimated.