First electroanalytical studies of methoxyfenozide and its interactions with dsDNA

Abstract The widespread use of pesticides is one of the major health and environmental concerns. There is an urgent need to develop improved analytical methodologies as well as for a deep insight into the mechanism behind the interaction between pesticides and the nucleic acids of living organisms. In the present work, the electrochemical behavior of the diacylhydrazine insecticide methoxyfenozide (Met) on a boron-doped diamond electrode and its interaction with double-stranded DNA (dsDNA) were investigated for the first time by applying cyclic voltammetry and square-wave (SW) voltammetry. The influence of numerous factors, such as composition of the supporting electrolyte, its pH, and voltammetric parameters, was analyzed. Under the optimized conditions, a simple and sensitive SW voltammetric procedure was developed for the determination of Met. Quantification was found to be linear from 5.0 × 10−7 to 7.0 × 10−5 mol L−1, with a detection limit of 1.4 × 10−7 mol L−1. The application of the developed voltammetric methodology for the analysis of tap water, river water and grape juice was tested with spiked samples. Studies on the interaction between methoxyfenozide and double-stranded salmon sperm DNA were conducted using both voltammetric and spectroscopic techniques. The results obtained indicated the dominance of the intercalative binding mode between Met and dsDNA. The binding constants of the formed complex were calculated based on the changes in the electrochemical and spectroscopic behaviors of Met in the presence of dsDNA.