Electrochemical immobilisation of enzymes: Part II. Glucose oxidase immobilised in poly-N-methylpyrrole

Electrochemical polymerisation of N-methylpyrrole in buffered aqueous solution containing the enzyme glucose oxidase produces adherent films at the electrode surface containing the active enzyme. Electrodes prepared in this manner can be used to detect glucose in solution in the range 0–0.22 mol dm−3. The observed response from such electrodes as a function of glucose concentration, enzyme loading, and film thickness are in excellent agreement with theory. From a comparison of the experimental results and the theory we are able to characterise the enzyme kinetics and diffusion within the conducting polymer film. The results are consistent with a model in which the hydrogen peroxide produced by the enzymatic reaction reacts at the electrode surface and not at the polymer itself.