Sol–gel derived iridium composite glucose biosensor

Iridium powder is introduced into sol–gel process for the first time to fabricate a novel type of sol–gel derived metal composite electrode. The iridium ceramic electrode shows excellent electrocatalytic action for both oxidation and reduction of hydrogen peroxide. The glucose biosensor based on sol–gel derived iridium composite electrode was fabricated. The biosensor shows highly selectivity towards glucose because of the strong catalytic action of iridium composite matrix for enzyme-liberated hydrogen peroxide at low operating potential, at which common interferences cannot be sensed. The novel type of biosensor can be renewed by simply mechanical polishing with favorable reproducibility and long-term stability.