利用3-噻吩丙二酸修饰玻碳电极检测粮油中残留苯嗪草酮

Determination of metamitron residue in cereal and oil using poly (3-thiophenemalonic acid) modified glassy carbon electrode

利用电化学聚合法制备3-噻吩丙二酸修饰玻碳电极，应用循环伏安法研究苯嗪草酮在3-TPA修饰玻碳电极上电化学行为，考察pH值、富集时间、扫描速率及扫描范围等条件对该修饰电极检测苯嗪草酮影响。在最佳条件下，利用差分脉冲伏安法得出苯嗪草酮浓度在9．77×10^-7～6．25×10^-5mol／L范围内呈良好线性关系，相关系数r=0．9998，检测限为9．77×10^-7mol／L。面粉、米粉和花生油样品加标回收率分别为99．2％、100．1％、93．9％，相对标准偏差为0．17％、0．25％、0．49％。

In this paper, poly （ 3-thiophenemalonic acid ） modified glassy carbon electrode was prepared by electrochemical polymerization, and the electrochemical behavior of metamitron was studied on the modified electrode using cyclic voltammetric method. Effects of pH value of buffer solution, accumulation time, scan rate and range were also studied and the optimum conditions were gained. Under optimum conditions, the modified electrodes showed a linear response over a metamitron concentration range of 9.77 × 10^-7 and 6.25 ×10^-5mol/L with 9.77 × 10^-7 mol/L of LOD, r=0.9998. The recoveries of metamitron added in wheaten flour, rice flour and peanut oil samples were 99.2%, 100.1% and 93.9% for 3 measurements with the relative standard deviations were 0.17%,0.25% and 0.49%, respectively.