Cobalt ferrite nanoparticles decorated on exfoliated graphene oxide, application for amperometric determination of NADH and H2O2

Here, cobalt ferrite nanocomposite decorated on exfoliated graphene oxide (CoFe2O4/EGO) was synthesized. The nanocomposite was characterized by different methods such as X–ray diffraction spectroscopy, scanning electron microscopy, energy dispersive X–ray diffraction microanalysis, FT-IR, Raman spectroscopy and electrochemical methods. The CoFe2O4/EGO nanocomposite was used to modify glassy carbon electrode (GCE). The voltammetric investigations showed that CoFe2O4/EGO nanocomposite has synergetic effect towards the electro-reduction of H2O2 and electro-oxidation of nicotinamide adenine dinucleotide (NADH). Rotating disk chronoamperometry was used for their quantitative analysis. The calibration curves were observed in the range of 0.50 to 100.0 µmol L–1 NADH and 0.9 to 900.0 µmol L–1 H2O2 with detections limit of 0.38 and 0.54 µmol L–1, respectively. The repeatability and reproducibility of the electrochemical sensor for NADH and H2O2 analysis were studied too. The selectivity of the electrochemical sensor was investigated. The new electrochemical sensor was successfully was applied for the determination of NADH and H2O2 in real samples with satisfactory results.