Switchable hydrophilicity solvent-based microextraction coupled with fluorescent detection of dichlorvos

Abstract

The risk of the hazardous pesticide dichlorvos (DDVP) entering the human body through aquatic products is causing concern as global demand for aquatic products increases. Herein, a novel approach ground on switchable hydrophilicity solvent-based microextraction coupled with fluorescent detection of DDVP in aquatic products was established. Sodium nonanoate, a switchable hydrophilic solvent, was converted into nonanoic acid in-situ for use as an extractant under acidic conditions to extract DDVP from aquatic products. Thereafter, DDVP was hydrolyzed to dichloroacetaldehyde (DCA) by adjusting the extraction solution to an alkaline condition. The fluorescent substances were generated due to the condensation reaction of DCA and resorcinol which can achieve the quantification of DDVP. The assay had a linear relationship between 40 and 280 μg kg−1, with a limit of detection of 2.4 μg kg−1. The assay has been used to determine the residual content of DDVP in grass carp, sea cucumber, and abalone samples. The recoveries ranged from 93.8% to 106%. The strategy integrating microextraction and detection offers insight into monitoring pesticides in food products.