High-performance glucose amperometric biosensor based on magnetic polymeric bionanocomposites

One-pot chemical oxidation of 1,6-hexanedithiol (HDT) in its aqueous suspension containing glucose oxidase (GOx) and Fe3O4-Au nanocomposites by 1,4-benzoquinone yields novel Fe3O4-Au-poly(HDT) (PHDT)-GOx magnetic polymeric bionanocomposites (MPBNCs) with GOx immobilized at high load and high activity. Transmission/scanning electron microscopy and UV-vis spectro photometry are used to characterize the prepared MPBNCs. A Fe3O4-Au-PHDT-GOx/Au electrode has been prepared by facile and efficient magnetism separation/immobilization of the MPBNCs onto an Au magnetism-electrode for biosensing of glucose, which exhibits high detection sensitivity (110 mu A cm(-2) mM(-1)), low detection limit (0.33 mu M, S/N = 3), rapid response time (<5 s), and excellent anti-interferent ability and stability. The biosensor performs better than those based on the existing protocols of conventional electropolymerization and chemical preoxidation/electropolymerization of monomer. The chemical oxidation synthesis and magnetism separation/immobilization protocol proposed here for convenient preparation and surface immobilization of functional MPBNCs of the target biomolecules may have application potential in many fields, such as biosensing, biocatalysis, biofuel cells, and bioaffinity separation. (C) 2009 Elsevier B.V. All rights reserved.