Covalent immobilization of glucose oxidase to poly(O‐amino benzoic acid) for application to glucose biosensor

A biosensor for glucose utilizing glucose oxidase (GOX) covalently coupled to poly(o‐amino benzoic acid) (PAB; a carboxy‐group‐functionalized polyaniline) is described. Amperometric response measurements conducted via unmediated and mediated (with ferrocene carboxylic acid and tetrathiafulvalene) reoxidation of GOX show that glucose can be detected over a wide range of concentrations. An enzyme‐conducting polymer‐mediator model provides for better charge transport in a biosensor. The optimal response, obtained at pH 5.5 and 300 K, lies in the 1–40 mM range. A kinetic plot yields the value of the apparent Michaelis–Menten constant, K_m^app. The operational stability of the PAB‐based glucose biosensor was experimentally determined to be about 6 days. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 662–667, 2000