Glucose Oxidase/Polypyrrole Biosensor Fabricated by Galvanostatic Electropolymerization Accompanied with a Potential Jumping

摘要

A novel and interesting micro-doughnut structure of glucose oxidase (GODX) was found after fabricating the galvanostatic glucose biosensor. By comparing with the structure reported, this doughnut structure was quite different. Due to the instantaneous voltage jumping from 0.95 to 1.7 V versus Ag/AgCl in the galvanostatic polymerization of pyrrole with commercial GODW the original, dentritic structure of enzyme bundled with polypyrrole (Ppy) became to be doughnut type. Results confirmed that the sensor with doughnut type enzyme possessed of better sensitivity to than that with dentritic type GODX fabricated from potentiometry or mild voltage elevating galvanometry for similar preparing conditions. The sensor with doughnut enzyme also exhibited two-week long-term stability. The discovery of doughnut type enzyme by this electro-modification process may also disclose a novel method for altering the protein structure.