The use of hybrid electrochemical double-stranded DNA/2′-deoxyguanosine 5′-monophosphate (bio)sensors based on anodically pre-treated “basal-plane” pyrolytic graphite electrode for monitoring of the interaction between double-stranded DNA and neonicotinoid insecticide clothianidin

Abstract

We present the utilization of the novel hybrid electrochemical DNA biosensor, as well as the fabrication and testing of novel dGMP (2′-deoxyguanosine 5′-monophosphate) (bio)sensor based on anodically pre-treated “basal-plane” pyrolytic graphite electrode (BPPGE) for the investigation of the interaction between double-stranded DNA (dsDNA) and neonicotinoid insecticide clothianidin (CLOT) via linear-sweep voltammetry (LSV). The results clarify the nature of the interaction as partial-intercalation (marked by high preference towards guanine bases) with binding constant (Kb) of 8.1 × 105 L/mol, free Gibbs energy (∆G0) of −33.154 kJ/mol, and site-binding size (s) of 0.58 bp. The conclusions obtained by LSV are further supported by molecular docking that confirmed a partial-intercalative mode of interaction with the predominant involvement of the hydrogen bonds (exclusively with the guanine bases) for the stabilization of dsDNA-CLOT complex.