Glucose Biosensor Based on Immobilization of Glucose Oxidase in Electrochemically Polymerized Polytyramine Film and Overoxidised Polypyrrole Film on Platinized Carbon Paste Electrode

An amperometric glucose biosensor has been developed based on immobilization of glucose oxidase (GOD) in electrochemically polymerized polytyramine (PTY) and overoxidised polypyrrole (OPPY) on platinized carbon paste electrode (PCPE). By providing a large apparent surface area with the micropores of the electrodeposited platinum particles on the PCPE, GOD was added, and the sensor was more sensitive. Owing to the polymerized polytyramine film and overoxidised polypyrrole film on the PCPE, the sensor was more anti-interferential and more stable. The sensor responds toβ-D-glucose linearly over a concentration range of 1 × 10−5–1.8 × 10−2 M, and the detection limit is 5 × 10−6 M. The response time of the sensor is less than 10 s, and the life time is over 2 months. Due to the permselective characteristics of PTY film and OPPY film, the effects of electroactive interferents, such as ascorbic acid, uric acid, and fructose, can be significantly reduced.