Amperometric nonenzymatic glucose sensor based on a glassy carbon electrode modified with a nanocomposite made from nickel(II) hydroxide nanoplates and carbon nanofibers

We report on a highly sensitive and selective nonenzymatic glucose sensor based on a glassy carbon electrode modified with a composite prepared from nickel(II) hydroxide nanoplates and carbon nanofibers. The nanocomposite was characterized by scanning electron microscopy and powder X-ray diffraction. Electrodes modified with pure Ni(OH)(2) and with the nanocomposite were characterized by electrochemical impedance spectroscopy. Cyclic voltammetric and amperometric methods were used to investigate the catalytic properties of the modified electrodes for glucose electrooxidation in strongly alkaline solution. The sensor exhibits a wide linear range (from 0.001 to 1.2 mM), a low detection limit (0.76 mu M), fast response time (< 5 s), high sensitivity (1038.6 mu A center dot mM(-1) center dot cm(-2)), good reproducibility, and long operational stability. Application of the nonenzymatic sensor for monitoring glucose in real samples was also demonstrated.