Amperometric glucose biosensor based on the deposition of copper and glucose oxidase onto glassy carbon transducer

The performance of a first generation glucose amperometric biosensor based on the entrapment of glucose oxidase (GOx) within a net of copper electrode posited onto activated glassy carbon electrode, is described. The copper el ectrodeposited offers an efficient electrocatalytic activity towards the re duction of enzymatically-liberated hydrogen peroxide, allowing for a fast a nd sensitive glucose quantification. The influence of the electrodeposition conditions (pH, potential, time, copper salt and enzyme concentrations) on the response of the bioelectrode was evaluated from the amperometric signa ls of hydrogen peroxide and glucose. The combination of copper electrodepos ition with a nafion membrane allows an excellent selectivity towards easily oxidizable compounds such as uric and ascorbic acids at an operating poten tial of -0.050 V. The response is linear up to 2.0 x 10(-2) M glucose, the detection limit being 1.2 x 10(-3) M.