Gold-coated silica-fiber hybrid materials for application in a novel hydrogen peroxide biosensor

We describe the preparation and characterization of a novel type of core-shell hybrid material for application in a novel hydrogen peroxide biosensor, where the structure consists of a continuous gold shell that encapsulates the silica fiber. The SiO2@Au nanofibers had been synthesized by electrospinning silica sol, and then golden seeds were in situ grown on the fiber, lastly the gold-seeded silica fibers were further coated by continuous gold shells. The above nanocomposites had satisfactory chemical stability, excellent biocompatibility and efficient electron transfer property, which may have potential application for the highly sensitive chemical or biological sensors. Cyclic voltammetry (CV) was used to evaluate the electrochemical performance of the SiO2@Au nanocomposites at indium tin oxide (ITO). The biosensor showed high sensitivity and fast response upon the addition of H2O2 and the linear range to H2O2 was from 5 x 10(-6) to 1.0 x 10(-3) M with a detection limit of 2 mu M (S/N =3). The apparent Michaelis-Menten constant of the biosensor was 1.11 mmol L-1. These results indicated that SiO2@Au nanocomposites have potential for constructing of a variety of electrochemical biosensors. (C) 2012 Elsevier B.V. All rights reserved.