热溶液中Nafion膜电极电化学分析法测定偶氮二甲酰胺

摘要

基于偶氮二甲酰胺在热溶液中的高溶解度及其与Nafion膜电极的静电作用,建立了偶氮二甲酰胺的电化学分析法.考察了偶氮二甲酰胺溶解度的温度效应,研究了偶氮二甲酰胺在Nafion膜电极上还原反应的机理.利用热溶液中偶氮二甲酰胺在Nafion膜电极上的伏安响应,用差分脉冲伏安法测定了面粉中的偶氮二甲酰胺含量.在水浴恒温80℃、pH 6.0的实验条件和优化的测试参数下,Nafion膜电极的电流响应与偶氮二甲酰胺的浓度在0.93～ 10.5 μg/L范围内呈线性关系,检出限为0.58 μg/L(S/N=3),对实际样品测定的相对标准偏差小于5.9％,回收率为95.8％ ～ 104.0％,氨基脲和呋喃西林不干扰偶氮二甲酰胺的测定.%Based on the high solubility of azodicarbonamide (ADC) in hot solution and its electrostatic interaction with Nafion film,a new electroanalytical method was developed for the determination of ADC by using Nafion film electrode.The effect of temperature on the solubility of ADC and the mechanism of the reduction reaction of ADC on Nafion film electrode were investigated.Under the experimental conditions such as water bath at a constant temperature of 80 ℃,pH 6.0 and optimal test parameters,the differential pulse voltammetric response was proportional to the concentration of ADC in the range of 0.93-10.5 μg/L,and the detection limit was estimated to 0.58 μg/L.The relative standard deviation was less than 5.86 ％ and the recovery was 95.8％-104.0％ for the determination of the ADC in flour samples.The semicarbazide and nitrofurazone did not interfere with the determination of ADC.