异烟肼在10-甲基吩噻嗪修饰碳糊电极上的电催化氧化及电分析方法___

目的：研究了异烟肼(Isoniazid,INH)在10-甲基吩噻嗪修饰碳糊电极(10-methylphenothiazine modified carbon paste electrode，MPT/CPE)上的电化学行为和电化学分析方法。方法：循环伏安法 (Cyclic voltammetry,CV)、计时电流法(Chronoamperometry，CA)和方波伏安法(Square wave voltammetry，SWV)。结果：INH在碳糊电极(Carbon paste electrode，CPE)上的直接电化学氧化过程十分迟缓，MPT/CPE对INH电化学氧化具有良好的催化作用。同时测定了INH在MPT/CPE上的电极过程动力学参数，用方波伏安法(SWV)测得催化氧化峰电流与INH在5.0×10-7~1.0×10-4 mol•L-1浓度范围内呈良好线性关系，线性回归方程为Ipa(μA)=186.63C (10-3 mol•L-1)+30.30，r=0.9971，检出限为2.1×10-7 mol•L-1(S/N=3)。结论：本方法灵敏度高，操作简单，可用于INH电化学定量测定。

Objective:Electrochemical behaviors,electrochemical kinetic parameters and electroanalysis of isoniazid (INH) at carbon paste electrode(CPE) and 10-methylphenothiazine modified carbon paste electrode (MPT/CPE) were investigated.Methods:Cyclic voltammetry(CV),chronoamperometry(CA) and square wave voltammetry(SWV).Results:It was found that isoniazid itself showed a poor electrochemical response at carbon paste electrode (CPE),the electrochemical behaviors could be greatly improved by using MPT/CPE,which enables a sensitive electrochemical determination of the substrate isoniazid.The kinetic parameters of the reaction were evaluated.The catalytic oxidation peak current of isoniazid versus its concentration had a good linear relationship in the concentration range of 5.0×10-7-1.0×10-4 mol•L-1with the correlation coefficient of 0.9971,and the detection limit of 2.1×10-7 mol•L-1 by Square wave voltammetry(SWV).Conclusion:The result can be applied in isoniazid electrochemical determination with both low detection limit and high sensitivity.