GALACTOSE BIOSENSORS USING COMPOSITE POLYMERS TO PREVENT INTERFERENCES

A biosensor using a composite polymer to prevent interferences was use d in a flow injection analysis system for the detection of galactose i n human plasma. The biosensor consisted of galactose oxidase immobiliz ed on a platinized carbon electrode that had been modified with a comp osite polymer. The composite polymer showed improved selectivity to hy drogen peroxide compared with either of its individual polymeric compo nents, Nafion and a copolymer of diaminobenzene and resorcinol. The co mposite polymer minimized the effect of possible interference from ura te, ascorbate, and acetaminophen. This analytical system had a minimum detection limit of 50 mu M, linearity to 6 mM, a storage stability of greater than 30 days, and a high sample throughput (approx. 120 sampl es/h).