A novel NiO/C@rGO nanocomposite derived from Ni(gallate): A non-enzymatic electrochemical glucose sensor

The development of suitable substrate materials in electrochemical sensors is essential for rapid and reliable quantification in the diagnostic and clinical fields. In this paper, NiO/C@rGO nanocomposite was synthesized through nickel (gallate) pyrolysis with graphene oxide and employed as a substrate to construct a glucose sensor with high selectivity and sensitivity. The structural characterizations of NiO/C@rGO were assessed by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, energy disperse spectroscopy, and elemental mapping. The newly fabricated biosensor (NiO/C@rGO/GCE) exhibited a high sensing performance with an extensive dynamic linear range (from 1 μM to 1115 μM) and a low limit of detection (LOD) 0.658 μM (S/N = 3) toward glucose. In addition, the NiO/C@rGO-based sensor displayed good stability, favorable repeatability, and anti-interference ability for determining glucose. It was also used to measure glucose in serum samples, and satisfactory results were attained. These results illustrated that the NiO/C@rGO nanocomposite could be applied as an excellent electrochemical sensing material with high sensitivity to diagnose glucose-related illnesses.