鲁米诺-十六烷基三甲基溴化铵介质中敌敌畏农药的电化学发光检测

Electrochemiluminescence detection of dichlorvos pesticide in luminol-CTAB medium.

作者信息

Chen Xiao-Mei, Lin Zhi-Jie, Cai Zhi-Min, Chen Xi, Wang Xiao-Ru

机构信息

Department of Chemistry and Key Laboratory of Analytical Sciences of the Ministry of Education, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.

出版信息

Talanta. 2008 Sep 15;76(5):1083-7. doi: 10.1016/j.talanta.2008.05.007. Epub 2008 May 16.

DOI:10.1016/j.talanta.2008.05.007

PMID:18761159

Abstract

A simple, novel electrochemiluminescence (ECL) method for the detection of dichlorvos pesticide (DDVP) with high sensitivity was discovered. Detection was carried out in a static ECL system, in which a glassy carbon electrode was selected as the working electrode. ECL parameters, including the concentrations of cetyrltrimethylammonium bromide and luminol, the solution pH, and the scan rate of the applied potential, were optimized. Under these optimal conditions, the linear response of ECL-emission versus DDVP concentration was valid in the range 5-8000 ng/L (r(2)=0.9982) with a relative standard deviation of 4.3% at 2000 ng/L (n=10), yielding a detection limit (S/N=3) of 0.42 ng/L. The ECL emission was caused by a radical reaction process, in which the dissolved oxygen in the luminol solution reacted with the DDVP and generated free radicals. The free radicals reacted with the luminol anion and yielded the luminol radical. The approach presented was successfully applied to the determination of DDVP residues in vegetable samples.

摘要

发现了一种简单、新颖的用于高灵敏度检测敌敌畏农药（DDVP）的电化学发光（ECL）方法。检测在静态ECL系统中进行，其中选择玻碳电极作为工作电极。优化了包括十六烷基三甲基溴化铵和鲁米诺浓度、溶液pH值以及施加电位的扫描速率等ECL参数。在这些最佳条件下，ECL发射与DDVP浓度的线性响应在5 - 8000 ng/L范围内有效（r(2)=0.9982），在2000 ng/L时相对标准偏差为4.3%（n = 10），检测限（S/N = 3）为0.42 ng/L。ECL发射是由自由基反应过程引起的，其中鲁米诺溶液中的溶解氧与DDVP反应并产生自由基。自由基与鲁米诺阴离子反应生成鲁米诺自由基。所提出的方法成功应用于蔬菜样品中DDVP残留量的测定。