生理介质中苦参碱和槐定碱的电化学动力学性质研究

Study on electrochemical kinetics of matrine and sophoridine in a physiological medium

目的:在生理介质中研究苦参碱和槐定碱在玻碳电极上的电化学动力学性质.方法:运用循环伏安法考察了苦参碱和槐定碱的直接电化学氧化行为,用控制电位电解库仑法、计时库仑法、计时电流法测定并计算了它们的电化学动力学参数.结果与结论:在0.30～1.2 V电位窗口内,MT和SR均产生1个不可逆氧化峰,并且它们的电极反应均受扩散步骤控制;用控制电位电解库仑法和循环伏安法得到MT和SR的电极反应电子转移数n和电荷转移系数α,运用计时库仑法和计时电流法测定了它们的扩散系数D及电极反应速率常数kf.

Objective： To investigate the kinetic processes of direct electrooxidation for both matrine and sophoridine in a physiological medium. Method： Their direct electrooxidative behaviors and the parameters of electrochemical kinetics were obtained by cyclic vohammetry （CV）, bulk electrolysis with coulometry, chronocoulometry （CC）, chronoampemmetry （CA）. Result and conclusion： The electrochemical experimental results show that the two totally irreversible oxidation peaks in the region of 0.3-1.2 V vs SCE for both MT and SR were observed, and the electrode reactions processes were diffusion-controlled. Their electron transfer number n and electron transfer coefficient α were obtained by CV and electrolysis with coulometry. The diffusion coefficient D and rate constant kf were also calculated by CC and CA.