Determination of chlorpyriphos in broccoli using a voltammetric acetylcholinesterase sensor based on carbon nanostructure–chitosan composite material

Abstract

The widespread use of organophosphate pesticides (OPPs) in agriculture leads to residue accumulation in the environment, which is dangerous to human health and disrupts the ecological balance. This study reports results obtained by a standard chromatographic method (high performance liquid chromatography, HPLC) and an amperometric method for chlorpyriphos (CPF) determination in broccoli. Reversed-phase HPLC with UV–VIS detection was used for the separation, and the mobile phase was acetonitrile–water (75:25v/v). The electrochemical experiments were performed in phosphate buffer solutions at pH=7.4, with an incubation time of 10min. The response of the sensor was a linear function of CPF concentration from 10−10 to 10−7M with a corresponding equation: y=0.1467x+1.4472 (R2=0.9959) and a detection limit of 1.58×10−10M. The biosensor methodology was used to analyze CPF directly in broccoli that had been previously spiked with CPF solution.