Electrodes modified with monoolein cubic phases hosting laccases for the catalytic reduction of dioxygen.

An enzyme-catalyzed process has been used for dioxygen monitoring. The enzymes were two different laccases (p-diphenol:dioxygen oxidoreductases), chosen as catalysts for dioxygen reduction. The laccases were immobilized in a liquid crystalline cubic phase formed with monoolein. The structures of the cubic phases, both with and without enzymes, were established using small-angle X-ray scattering. The catalytic reduction of dioxygen was performed using a glassy carbon electrode modified with cubic phases containing the enzymes. The modified electrode was used as a dioxygen sensing system, based on the increasing reduction current of a suitable electrochemical probe in the presence of dioxygen.