Synthesis and characterization of nickel oxide hollow spheres-reduced graphene oxide-nafion composite and its biosensing for glucose

A novel composite film of nickel oxide hollow spheres (NiOHSs)-reduced graphene oxide (RGO)-nafion (NF) modified glassy carbon electrode (NiOHSs-RGO-NF/GCE) was successfully fabricated via a facile, effective and general strategy and applied in the sensitive and selective determination of glucose. The synthetized nickel oxide was characterized by the hollow spheres with porous surface. The composition, morphology, and structure of the as-prepared NiOHSs-RGO were characterized by the techniques such as Raman spectroscopy, powder X-ray diffraction, energy-dispersive X-ray spectrum, scanning electron microscopy and transmission electron microscopy. Compared with the bare GCE, RGO-NF/GCE, and NiOHSs-NF/GCE electrodes, the NiOHSs-RGO-NF/GCE had higher catalytic activity toward the oxidation of glucose. Under the optimal conditions, selective detection of glucose in a linear concentration range of 0.6246 mu M-10.50 mM was obtained with the limit of 0.03 mu M (3S/N). Moreover, the proposed method was successfully applied to determine glucose in real serum sample with satisfactory results. The results showed that the modified electrode exhibits an excellent catalytic activity, good selectivity, reproducibility, and long-term stability. (C) 2014 Elsevier B.V. All rights reserved.