基于聚邻苯三酚修饰的甲霜灵分子印迹传感器制备与应用

摘要

To develop a rapid and accurate method for determining metalaxyl residues in tobacco, a molecular imprinted sensor was prepared by electropolymerizing phenol on the surface of pyrogallol modified glassy carbon electrode with metalaxyl as the template under weak alkali conditions. The sensor was characterized by cyclic voltammetry and tested by differential pulse method. The results showed that: 1) The optimized preparation condition for this sensor was template/functional ratio 1/16, electropolymerization basement solution in a borax buffer with pH 9.0, and the elution time 20 min. 2) Under the optimized experimental condition, the limit of detection, recoveries, relative standard deviations (RSDs) of the developed method were 0.003 mg/kg, 98.5%-113.7% , 2.98%-4.26% , respectively. 3) The sensor was simple in application and rapid in responses and featured a high selectivity, it was suitable to the determination of metalaxyl residue in tobacco.%为快速、准确测定烟草农药残留甲霜灵,在弱碱条件下,以邻苯三酚为修饰材料,甲霜灵为模板,苯酚为功能单体,采用电聚合法在玻碳电极表面成功制备对甲霜灵有高选择性和灵敏度的分子印迹电化学传感器,并采用循环伏安法、差示脉冲法对其进行表征和测试.结果表明:①优化确定的制备该传感器的条件为模板/单体摩尔比1∶16,聚合基底液为pH=9.0的硼砂缓冲液,洗脱时间20 min.②在优化的实验条件下,该传感器测定甲霜灵的检出限为0.003 mg/kg,加标回收率为98.5%~113.7%,相对标准偏差为2.98%~4.26%.③该传感器应用方便,测定速度快,选择性高,适用于烟草农药残留甲霜灵的测定.