银微盘电极上谷胱甘肽降解产物的伏安行为

Voltammetric Behavior of Degradation Product of Glutathione at Silver Microdisk Electrode

谷胱甘肽是一个含硫三肽 ,基于谷胱甘肽降解产物中的L_半胱氨酸 (RS- )能与Ag+形成难溶化合物的性质 ,在银微盘电极上研究了其水解产物的伏安行为 ;运用示差脉冲溶出伏安法 (DPSV) ,在0.1mol/LHAc -NaAc介质中 ,谷胱甘肽降解产物的还原峰电流与谷胱甘肽浓度于9.0×10-7～4.0×10-5 mol/L范围内有较好的线性关系 ,测定限为5.0×10 -8mol/L ,用于模拟样品测定 。

The voltammetric behavior of the degradation product of glutathione , L _ cysteine, at self _ assembled silver microdisk electrode in 0.1 mol/L HAc-NaAc buffer solution was investigated. The mechanism of electrode reaction was also discussed. Based on the production of a hardly soluble matter of L _ cysteine with Ag+, a method for the determination of glutathione was proposed by differential pulse cathodic stripping voltammetry. A linear range of 9.0×10-7～4.0×10-5 mol/L and a limit of determination of 5.0×10-8 mol/L for glutathione were obtained. The method was used for determing glutathione content in artificially mixed samples with satisfactory results.