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The authors describe a nonenzymatic glucose sensor that was obtained by electrochemical deposition and oxidization of metallic nickel on the surface of nitrogen-doped reduced graphene oxide (N-RGO) placed on a glassy carbon electrode (GCE). An analysis of the morphology and chemical structure indicated the composite to possess a well-defined vermicular Ni(OH) nanorods combined with N-RGO. The electrochemical performance of the modified GCE with respect to the detection of glucose in 0.1 M NaOH was investigated by cyclic voltammetry and amperometry. The wrinkle and protuberance of N-RGO for loading of nanostructured Ni(OH) are found to increase electrical conductivity, surface area, electrocatalytical activity and stability. The modified GCE displays a high electrocatalytic activity towards the oxidation of glucose in 0.1 M NaOH solution. The lower detection limit is 0.12 μM at an applied potential of +0.45 V (vs Ag/AgCl) (S/N=3), and the sensitivity is 3214 μA mM cm. The modified GCE possesses long-term stability, good reproducibility and high selectivity over fructose, sucrose and lactose. [ABSTRACT FROM AUTHOR]

A newly fabricated nitrogen-doped graphene (NGE) supported hemin composite was prepared with facile one-pot method deriving from graphene oxide. Hemin was directly anchored on the surface of NGE during the N-doping process with doping-reducing agent of 2-aminopyridine. XPS results revealed the nitrogen doping of graphene and the integration of Hemin with NGE, and the hemin-N C (H-NGE) composite was characterized with TEM and SEM. The peroxidase-like activity of hemin maintained, displaying fast redox property. The H-NGE also exhibited remarkable electrocatalysis towards O 2 and H 2 O 2 reduction due to the high-speed charge-transfer between hemin and the modified electrode. The good electroactivity of NGE and the excellent synergic effect enables an enhanced electrochemical performance. Based on the well-designed H-NGE, the electrocatalytic H 2 O 2 determinations was monitored amperometrically with a low detection limit (0.092 μM). [ABSTRACT FROM AUTHOR]