Electrochemical Integration of Au Nanoparticles into Poly(3,4-ethylenedioxythiophene) for Nonenzymatic Glucose Sensing

Electrochemical glucose oxidation is an important reaction applicable to various industrial fields, such as chemical processes, fuel cells, and electrochemical glucose sensors. In this study, we report the nonenzymatic electrode materials based on the hybrid materials composed of Au nanoparticles (AuNPs) and poly(3,4-ethylenedioxythiophene) (PEDOT) (Au/PEDOT) for the electrochemical glucose oxidation. The Au/PEDOT hybrid materials are prepared by constant potential electrolysis in the presence of tetrachloroaurate (III) (AuCl4–) using the PEDOT-coated indium tin oxide (ITO) substrate as a working electrode. The constant potential electrolysis performed under the potential, where the Au electrodeposition and the electrochemical doping of PEDOT simultaneously occur, realizes the uniform distribution of AuNPs in PEDOT and forms the network morphologies of AuNPs. The fabricated Au/PEDOT hybrid material shows electrocatalytic properties for the electrochemical glucose oxidation in phosphate buffer solution (PBS) (pH = 7.4), and its sensitivity is 28.0 μA mM–1 cm–2 with a linear concentration range enough to measure the blood sugar level.