Quinone‐modified polymers as electron transfer relay systems in amperometric glucose sensors

A polysiloxane and an acrylonitrile–ethylene copolymer with covalently attached p‐hydroquinone/benzoquinone moieties were prepared and tested as electron transfer relay systems in amperometric glucose biosensors. Using experiments involving cyclic voltammetry and stationary potential measurements, it was shown that the polysiloxane relay system can efficiently mediate electron transfer from reduced glucose oxidase to a conventional carbon‐paste electrode. Sensors containing this polymeric relay system and glucose oxidase respond rapidly to low (<0.1 mm) glucose concentrations, with steady state current responses achieved in less than 1 min. The acrylonitrile–ethylene copolymer was found to be less efficient than the polysiloxane system at mediating the electron transfer from reduced glucose oxidase to the electrode. The dependence of the sensor response on the nature of the polymer backbone is discussed.