将裸玻碳电极在0.2 mol/L NaH₂PO₄-Na₂HPO₄溶液中于+1.7 V恒电位处理400 s后，得到电活化玻碳电极（EGCE）。以EGCE为工作电极，研究了缓冲溶液、pH、富集时间、富集电压和扫描速度对甲氧苄啶（TMP）测定的影响。结果表明，EGCE对TMP有较高的电化学响应。通过差分脉冲伏安法测试，TMP的氧化峰电流与浓度分别在1.25×10^-7~3.0×10^-5 mol/L、3.0×10^-5~1.0×10^-4 mol/L范围内呈良好的线性关系，检出限为8.2×10^-8 mol/L （S/N=3）。该方法操作简单、快速，用于检测TMP的重现性和稳定性好。

An electro-activated glassy carbon electrode (EGCE) is prepared through activating a bare glassy carbon electrode (GCE) in a 0.2 mol·L^-1 NaH₂PO₄-Na₂HPO₄ buffer solution for 400 s by potentiostatic method at +1.7 V.By using ECGE as working electrode,the effects of buffer solution,pH,accumulation time,accumulation voltage and scanning rate on trimethoprim (TMP) detection are investigated.Study results show that EGCE has a higher electrochemical response to TMP than GCE.By differential pulse voltammetry,it is found that a linear relation exists between the oxidative peak current and the concentration of TMP under the optimal conditions,and the linear ranges are 1.25×10^-7 to 3.0×10^-5 mol·L^-1,3.0×10^-5 to 1.0×10^-4 mol·L^-1,respectively.The detection limit is 8.2×10^-8 mol·L^-1 (S/N=3).This method is simple,fast,reproducible and stable for detection of TMP.

兰天宇(1989-),男,硕士,实验师,研究方向为功能材料和电分析化学,tianyulan1989@163.com