Electrocatalytic Detection of Hydrogen Peroxide at a Poly(m-phenylenediamine)-modified Carbon Paste Electrode and its Use for Biosensing of Glucose

Abstract

Coverage of carbon paste electrodes with poly(1,3-phenylenediamine) (m-PPD) films results in an accelerated oxidation of hydrogen peroxide. Compared to the bare carbon surface, the coated electrode exhibits a substantial (240 mV) lowering of the oxidation potential and a marked enhancement of the current response. Variables affecting the electrocatalytic behavior, including the electropolymerization potential and time, monomer structure, or pH, are explored. Combining this electrocatalytic action of PPD films with their effective permselective/discriminative properties holds great promise for first-generation oxidase-based amperometric biosensors. For example, it leads to a greatly enhanced glucose response while maintaining an effective rejection of coexisting electroactive species.