Electroanalytical procedures for quantification of pesticides in commercial formulations

Abstract

Novel electroanalytical procedures are developed for determination of different pesticides content in commercial pesticide formulations using chronopotentiometry. As a working electrode glassy carbon electrode and thin film mercury electrode are used for determination of insecticide imidacloprid and herbicides metamitron and metribuzin. For all determined pesticides one reduction peak is obtained, as a result of irreversible reduction of the analyte on the working electrode. Quantification of pesticides in commercial formulations is performed after optimization and validation of the chronopotentiometric method. Samples of commercial pesticide formulations are primarily dissolved in doubly distilled water, acetonitrile and ethanol for imidacloprid, metamitron and metribuzin, respectively. Ultrasound treatment in duration of 2 min is used to support dissolution. The final dilution is performed in the BrittonRobinson buffer of optimal pH value. Quantitative determination of the pesticide is performed using the calibration curve method, while every sample is analyzed in triplicate. Obtained average recovery and RSD value for 13 samples of commercial pesticide formulations is 100.22% and 0.01%, indicating on the accuracy and precision of the chronopotentiometric method.