基于电化学技术的Ⅱ型拟除虫菊酯分子印迹膜的研制

拟除虫菊酯类农药残留造成的安全问题已受到越来越广泛的关注,开发快速检测技术可为农副产品中拟除虫菊酯类农药残留的监控提供技术支持。本实验以邻氨基酚为功能单体,以Ⅱ型拟除虫菊酯农药结构类似物间苯氧基苯甲酸为模板分子,采用循环伏安法电聚合技术在玻碳电极表面聚合形成可检测含间苯氧基苯甲酸结构的Ⅱ型拟除虫菊酯农药的分子印迹膜,用于Ⅱ型拟除虫菊酯类农药的检测研究。5 min可完成对农药的响应,其响应电流变化值与一定浓度范围内的溴氰菊酯、氰戊菊酯、甲氰菊酯、氯氟氰菊酯呈良好的线性关系,相关系数r分别为0.991、0.992、0.992、0.990,精密度分别为2.20%、2.80%、2.50%、2.12%,检出限在0.01mg/kg~0.30 mg/kg之间。对加标红桔、贡桔和椪柑样品进行检测,准确性高。

Preparation of Molecularly Imprinted Membrane for Type II-pyrethroid Determination Based on Electrochemical Technique

Recently, increasing attention has been paid to the hazards of pyrethroid insecticide residues. Rapid detection techniques can provide technical support for monitoring the pyrethroid pesticide residues in agricultural products. Using o-aminophenol (OAP) as the functional monomer and 3-phenoxybenzoic acid (3-PBA) (the structural analog of type II-pyrethroid insecticides) as the template molecule, the electropolymerized molecularly imprinted membrane (MIM) was prepared for the detection of type II-pyrethroid insecticides; MIM was synthesized on the surface of glassy carbon electrode (GCE) by the method of cyclic voltammetry in this study. The prepared MIM was applied in the detection of type II-pyrethroid insecticides and responses to the insecticides were completed within five minutes. The changes in the peak current value showed a good linear correlation with deltamethrin, fenvalerate, fenpropathrin, and cyhalothrin within a certain concentration range; the corresponding correlation coefficients were 0.991, 0.992, 0.995, and 0.990, respectively; precisions were 2.20%, 2.80%, 2.50%, and 2.12%, respectively; and detection limits ranged from 0.01 mg/kg to 0.30 mg/kg. The system was used for measurements of spiked citrus samples such as tangerine, Gong orange, and Ponkan, and results showed high accuracy.