摘要
研究了谷胱甘肽（还原型,glutathione,GSH）在10-甲基吩噻嗪（10-methylphenothiazine,MPT）修饰碳糊电极（MPT/CPE）上的电催化氧化行为。GSH在裸碳糊电极（carbon paste electrode,CPE）上的直接电化学氧化过程十分迟缓,但在MPT/CPE上于0.702 V处出现一个不可逆氧化峰,氧化电流大幅度增大。计时电流（chronoamperometry,CA）实验测得该电催化氧化反应速率常数k为（5.44±0.03）×10^2（mol.L^-1）^-1.s^-1。用线性扫描伏安法（linearsweep voltammetry,LSV）测得催化氧化峰电流与GSH在5.0×10^-6-2.0×10^-3mol.L^-1呈良好的线性关系,线性回归方程Ipa=3.536c＋2.117,r=0.999 0,检测限为1.0×10-6mol.L^-1。同时用本方法对含GSH的市售药品进行了含量测定,结果可靠。
The electrocatalytic oxidation of glutathione （reduced form GSH） at 10-methylphenothiazine （MPT） modified carbon paste electrode （MPT/CPE） was investigated by cyclic vohammetry （CV）. Although GSH itself showed a very poor electrochemical response at carbon paste electrode （ CPE）, the response could be greatly enhanced by using MPT/CPE, which enables a sensitive electrochemical determination of the substrate GSH. The reaction rate constant for catalytic oxidation was evaluated as （5.44± 0. 03 ） × 10^2 （mol · L^-1 ） ^-1 · s^-1 by using chronoamperometry （CA）. The catalytic oxidation peak current of GSH versus its concentration had a good linear relationship in the concentration range of 5.0 × 10^-6 -2.0 × 10^-3 mol· L^-1 with the correlation coefficient of 0. 999 0, and the detection limit of 1.0 × 10^-6 mol · L^-1 by linear sweep voltammetry （LSV）. The method can be applied for the determination of GSH in injection samples with the satisfactory results.
出处
《药学学报》
CAS
CSCD
北大核心
2008年第3期291-294,共4页
Acta Pharmaceutica Sinica
基金
宁夏高等学校科学研究项目(200623)资助
关键词
谷胱甘肽
10-甲基吩噻嗪
碳糊修饰电极
电催化氧化
线性扫描伏安法
glutathione
10-methylphenothiazine
modified carbon paste electrode
electrocatalytic oxidation
linear sweep voltammetry
