Detection of Carbendazim Residues in Aqueous Samples by Fluorescent Quenching of Plant Esterase

A method based on the inhibition of plant esterase from pesticides has been proposed and validated for the determination of carbendazim residues in aqueous samples. After optimization in pH, temperature, and detection time, a lower detection limit of 0.105 mu M was obtained in the linear range from 0.105 to 41.84 mu M. Upon analysis of the detection mechanism, carbendazim was found to be binding to plant esterase via the van der Waals force and the hydrogen bond with a single binding site through an exothermic reaction. Moreover, the proposed method was satisfactorily applied to the analysis of carbendazim residues in different aqueous samples, obtaining a remarkably good agreement with the standardized reference method.