One-step co-electropolymerized conducting polymer–protein composite film for direct electrochemistry-based biosensors

A novel meliorative conducting polymer–redox protein composite film was fabricated via one-step co-electropolymerization approach. With electrostatic interactions between the conducting polymer and the protein, the composite film possesses attractive features, especially in studies of direct electron transfer of redox proteins as well as the development of unique protein based biosensors. Electrochemical impedance spectroscopy (EIS), atomic force microscopy (AFM), reflectance absorption infrared spectroscopy (RAIR) and ultraviolet visible spectroscopy (UV–vis) were performed to characterize the unique film. The direct electron transfer of the redox protein in the composite film were explored, and its bioactivity was also investigated by catalyzing the reductions of H2O2 and NO2−, demonstrating its great potential applications in direct electrochemistry-based high performance biosensors.