玻碳汞膜电极上还原型谷胱甘肽的电化学行为及分析应用

利用循环伏安法(CV)研究了玻碳汞膜电极上谷胱甘肽(GSH)的电化学行为和定量测定方法.在含有GSH的B.R.缓冲溶液(pH=4.0)中,当汞膜电极处汞的氧化电位为正电位时,电极表面生成的亚汞离子与GSH作用生成配合物,并沉积在电极表面起预富集GSH的作用;当电极向负方向扫描时,CV图上出现灵敏的汞的阴极溶出峰电流,且该溶出峰电流与溶液中的GSH浓度呈良好的线性关系.利用该方法对基体成分简单的针剂中的GSH和植物提取液(枸杞)中的GSH含量进行了测定,并与显色光度法的测定结果进行了比较,结果表明两者基本吻合.对电极反应机理和影响阴极溶出伏安特性的像酸度、干扰成分、扫描速率及电流函数等因素作了探讨,并提出了电极反应机理.

Electrochemical Behavior of GSH on Mercury Film Elelctrode and Analytical Application to the GSH Determination

Cyclic voltammetric properties of reduced glutathione（GSH） and quantitatively analysis of GSH using mecury film electrode has been investigated. In Bristol buffer solution （pH = 4.0） containing GSH, meeury film oxidized at relatively positive potential and the formed mercury ions interact with GSH to form complex, which deposited and preconcentrated GSH on the electrode surface. As the potential is negatively scanned, sensitive cathodic stripping current is observed and the current is linearly related with the concentra- tion of GSH in the solution. Quantitative analysis of GSH in syringe sample and plant material （wolf berry） has been proceeded with this method and the results are corespondant with the results obtaiend by spectrome- tric methods. The electrochemical mechanism has been proposed according to the valuation of cyclic voltam- metric properties with different experiment conditions.