Enhanced Adsorption of Glucose Oxidase by Introducing Artificial Porosity into Polypyrrole Based Glucose Biosensors

A polypyrrole (PPy) based biosensor fabricated on a Pt plated nano-porous alumina electrode has been described. By selecting nano-porous electrodes, the enzyme adsorption has been increased and the usage of a cross linking agent has enhanced the performances of the sensor remarkably. A thin film of PPy/PF₆ ^- was synthesized with 0.05 M Pyrrole, 0.1 M NaPF₆ at a current density of 0.3 mA/cm² for 90 s. The immobilization was done by physically adsorbing 5 muL of glucose oxidase (GOx) on PPy thin film. Glutaraldehyde (0.1 wt.%, 5 muL)was used for cross-linking. The synthesized films were characterized by using amperometric electrochemical technique and scanning electron microscopy (SEM). Amperometric responses were measured as a function of different concentrations of glucose. Nanoporous electrodes lead to high enzyme loading. Stability, sensitivity, reproducibility and repeatability have been increased with the usage of cross-linking.