Effect of Gold Nanoparticles on the Structure and Electron Transfer Characteristics of Glucose Oxidase-Redox Polyelectrolyte-Surfactant Complexes.

M.L. CORTEZ; W. MARMISOLLÉ; D. PALLAROLA; L.I. PIETRASANTA; M. CEOLIN; D.H. MURGIDA; O. AZZARONI; F. BATTAGLINI

CHEMISTRY-A EUROPEAN JOURNAL

WILEY-V C H VERLAG GMBH

Lugar: Weinheim; Año: 2014 vol. 20 p. 13366 - 13374

0947-6539

Efficient electrical communication between redox proteins and electrodes is a critical issue in the operation and development of amperometric biosensors. The present study explores the advantages of nanostructured redox-active polyelectrolyte-surfactant complex containing [Os(bpy)2Clpy]2+ as redox centers and gold nanoparticles (AuNP) as nanodomains for boosting the electron transfer propagation throughout the assembled film in the presence of glucose oxidase (GOx). Film structure was characterized by grazing incidence small-angle X-ray scattering (GISAXS) and atomic force microscopy (AFM), GOx incorporation was followed by SPR and QCM-D, while Raman spectroelectrochemistry and electrochemical studies confirmed the ability of the entrapped gold nanoparticles to enhance the electron transfer processes between the enzyme and the electrode surface. Our results show that nanocomposite films exhibit 5-fold increase in current response to glucose when compared to analogous supramolecular AuNP-free films. The introduction of colloidal gold promotes drastic mesostructural changes in the film, which in turn leads to a rigid, amorphous interfacial architecture where nanoparticles, redox centers and GOx remain in close proximity, thus improving the electron transfer process.