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 0.05M Pyrrole, 0.1M NaPF6 at a current density of 0.3mA/cm2 for 90s. The immobilization was done by physically adsorbing 5µL of Glucose Oxidase (GOx) on PPy thin film. Glutaraldehyde (0.1wt.%, 5µL) 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.