Enhancement in Detection of Glucose Based on a Nickel Hexacyanoferrate-Reduced Graphene Oxide-modified Glassy Carbon Electrode

A new kind of electrode modified by depositing nickel hexacyanoferrate (NiHCF) and reduced graphene oxide (RGO) onto the surface of a glassy carbon electrode is proposed. Electrochemical property investigation demonstrated NiHCF nanoparticles formed on the surface of RGO retain their excellent electrochemical activity and the RGO can enhance the electron transfer between NiHCF nanoparticles and the glassy carbon electrode owing to the large surface of the RGO. The morphology of the NiHCF/RGO film was characterized by scanning electron microscopy. The electrochemical behaviour and electrocatalytic performance of the NiHCF/RGO glassy carbon electrode towards the oxidation of glucose were evaluated by cyclic voltammograms. Results showed that the NiHCF/RGO-modified electrode exhibits a pair of well-defined redox peaks. The linear range for the detection of glucose was 1.0 x 10(-6) to 1.7 x 10(-2) M and the detection limit was as low as 2.8 x 10(-7) M based on a signal-to-noise ratio of 3. The as-made sensor was applied to determine glucose levels in human blood serum with satisfactory results. In addition, the effects of common interfering species, including ascorbic acid, uric acid, dopamine, and some carbohydrates are discussed in detail.