An enhanced strategy using poly(m-aminobenzene sulfonic acid) nanofibres for rapid detection of DNA oxidative damage induced by hollow TiO2 nanocubes

A novel membrane comprising of hollow TiO2 nanocubes and poly(m-aminobenzene sulfonic acid) (PABSA) nanofibres was constructed on the glassy carbon electrode (GCE) for detecting the oxidative damage of natural dsDNA induced by TiO2 under UV radiation. The TiO2/PABSA membrane was used for efficient dsDNA immobilization, dsDNA oxidation through photogenerated hydroxyl radicals, and as the platform for electrochemical sensing. The properties of the TiO2/PABSA membrane and the immobilization of dsDNA were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy using [Fe(CN)6]3−/4− as the indicator. The resulting oxidative damage of dsDNA was detected by monitoring the CV response of an intercalated electroactive probe, namely, Co(phen)33+. PABSA has a profound synergistic effect with the hollow TiO2 on the DNA damage detection and the sensor has the potential of becoming a powerful tool for the rapid assessment of the genotoxicity of existing and new chemicals.