Determination of Glucose with Biosensor by Immobilization of Glucose Oxidase with Chitosan

A glucose biosensor was fabricated from a glucose oxidase-immobilized by chitosan and oxygen electrode.The effects of concentration of chitosan(0.3%),enzyme loading(0.8 mg),pH 7.0,phosphate buffer concentration(300 mmol/L),and temperature 25 ℃ for the response of the biosensor were investigated.The glucose biosensor has a linear response range of 0.016-1.10 mmol/L with a detection limit of 8.0 μmol/L(S/N=3).The response time was less than 60 s.The biosensor showed extremely good stability with a shelf-life of at least 3 months.The biosensor exhibited good repeatable response to a 0.25 mmol/L glucose solution with a relative standard deviation of 2.5%(n=10).The precision of fabrication of the biosensors using four different membranes was good with a RSD of 4.7%.Some common potential components in sample such as niacinamide,vitamin B6,vitamin B12,vitamin E,Ca2+,Mg2+,K+ and Zn2+ showed no interferences on the response of the glucose biosensor.The biosensor was successfully applied to determine the glucose in commercial beverage samples.