An amperometric glucose biosensor based on poly( o-aminophenol) and Prussian blue films at platinum electrode

Abstract

Prussian blue (PB), as a good catalyst for the reduction of hydrogen peroxide, has been combined with nonconducting poly( o-aminophenol) (POAP) film to assemble glucose biosensor. Compared with PB-modified enzymatic biosensor, the biosensor based on glucose oxidase immobilized in POAP film at PB-modified electrode shows much improved stability (78% remains after 30 days) in neutral medium. Additionally, the biosensor, at an applied potential of 0.0 V, exhibits other good characteristics, such as relative low detection limit (0.01 mM), short response time (within 5 s), large current density (0.28 mA/cm 2), high sensitivity (24 mA M −1 cm −2), and good antiinterferent ability. The apparent activation energy of enzyme-catalyzed reaction and apparent Michaelis–Menten constant are 34.2 KJ mol −1 and 10.5 mM, respectively. In addition, effects of temperature, applied potential used in the determination, pH value of the detection solution, and electroactive interferents on the amperometric response of the sensor were investigated and are discussed.