A composite magnetic particulates composed of Fe3O4/Au/glucose oxidese(Gox) was synthesized, which exhibited a good superparamagnetism. A novel amperometric biosensor has been developed for the determination of glucose based Fe3O4/Au/GOx particulate absorbed on the refit glassy carbon electrode through magnet. The performance of the sensor was studied by cyclic voltammetric and chronoamperometric techniques. In PBS of pH7.0, with the presence of the mediator of ferrocene ferrocene, a linear calibration plot was obtained in the glucose concentration range between 5.0×10-5～2.0×10-2mol/L, and the response time to glucose was less than 10s. The sensor exhibited high sensitivity, good selectivity and stability, due to the existence of nanometer Fe3O4 and nano-Au which maintain the enzymatic activity of glucose oxidase, and the sensor was easily to renew because the enzyme has a good magnetism.

Key words: magnetism, nano-Au, glucose oxidase, biosensor