PEDOT-GO Nanocomposites Based Detection of DNA Fragments Resulting from UV Induced dsDNA Damage

Abstract

DNA oxidative damage, particularly 8-oxoguanine (8-OxoG), is a biomarker of great significance as it leads to genomic instability and diseases, so a sensitive electrochemical platform to detect 8-oxoG using a poly(3,4-ethylenedioxythiophene) (PEDOT)/reduced graphene oxide (rGO)/ZnO nanocomposite have been proposed. The density functional theory (DFT) screening of the late transition metal oxide/rGO hybrids showed ZnO to be the most reactive matrix towards 8-oxoG, which is also consistently supported by the QTAIM, MEP and IRI analysis, which shows that Zn and O are partially covalently bonded and thus provides a strong interaction with the oxidative lesion of DNA. PEDOT/rGO-ZnO film was formed through the electropolymerization and electrodeposition processes on SPE and characterized using Fourier-transform infrared spectroscopy, scanning electronic microscopy and X-ray diffraction studies, which proved the successful synthesis of an effective and uniform hybrid network. The electrochemical performance was assessed by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). The partially covalent ZnO-rGO interface increases stability and charge transfer, making the PEDOT/rGO-ZnO composite a promising device in real- time on-site detection of oxidative DNA damage.