基于聚吡咯纤维-纳米金修饰BDD电极对亚硝酸盐的检测

Determination of nitrite based on PPy/AuNPs modified BDD electrode

利用聚吡咯纤维/纳米金(PPy/AuNPs)修饰硼掺杂金刚石(BDD)电极对亚硝酸盐进行检测.2×10-3mol/L亚硝酸盐在不同电极上的差分脉冲伏安结果表明PPy/AuNPs具有较高的电催化活性.实验研究了不同pH的缓冲液和修饰量对电极响应的影响,得出最佳缓冲液pH值为5,最佳修饰量为15μL.在最优条件下,亚硝酸盐的浓度与其峰电流在50~400μmol/L范围内呈线性关系,线性方程为Ip=0.003 96c+0.011 79(R^2=0.995 5),检出限为0.66μmol/L.采用本方法对实际样品中的亚硝酸盐的含量进行测定,平均回收率为93.62%~99.23%.

The polypyrrole（PPy）fibers modified boron-doped diamond（BDD）electrode has been successfully developed for the detection of nitrite.Differential pulse voltammetry was used to investigate the properties of the bare BDD electrode and the PPy/AuNPs-BDD electrode in a2×10-3 mol/L nitrite solution.The results indicated that PPy/AuNPs had higher electrocatalytic activity.The effect pH of different buffer solutions and modified quantity on the electrode response was investigated,and the results showed that the optimal buffer solution pH was 5and the optimal modified quantity was 15μL.Under the optimized condition,the peak currents was proportional to nitrite concentration ranging from 50 to 400μmol/L,and the linear equation was Ip= 0.003 96 c ＋ 0.011 79（R2=0.995 5）,with a detection limit of 0.66μmol/L.This method could be used for detecting nitrite in practical samples using the PPy/AuNPs-BDD electrode,the average recovery was 93.62%-99.23%.