Immobilization of alcohol dehydrogenase on poly[1-(2-carboxyethyl)pyrrole] film for fabrication of ethanol-responding electrode

Alcohol dehydrogenase (ADH) was immobilized on the film of poly[1-(2-carboxyethy] pyrrole], which was prepared by electrochemical polymerization of 1-(2-carboxyethyl)pyrrole. The film exhibited a stable conductivity of 10−4-10−3 S/cm over the temperature range 0-200 °C. A significant amount of ADH (50-100 g/cm2) was immobilized on the polymer film by use of a condensing reagent. Although activity of ADH was decreased by the immobilization, the ADH-immobilized polymer film showed amperometric response to ethanol at +0.85 V vs. SCE in the presence of nicotinamide adenine dinucleotide (a redox mediator). These results demonstrate that the polymer film acts as both an ADH-supporting layer and a conductive medium in the alcohol-driven amperometric device.