A novel green synthesized NiO nanoparticles modified glassy carbon electrode for non-enzymatic glucose sensing

A novel nickel oxide nanoparticles modified glassy carbon electrode was fabricated and used as a non enzymatic sensor for glucose determination. Aimed as promising alternative to conventional chemical methods, NiO-NPs were synthesized via a green synthetic approach using Nigella sativa Extract. NiO NPs were characterized using Fourier transfer infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy with EDS profile. Electrochemical measurements were performed using cyclic voltammetry (CV) and Chrono-ammperometry (CA) in 0.1 M NaOH solutions, revealing a well defined redox couple of NiIII/NiII. The electrogenerated NiIII species on the electrode surface act as an excellent catalyst toward the glucose oxidation reaction. Our modified electrode presents good stability, short response time < 3 s, low detection limit around 3.2 µM, and two linear ranges of detection from 50 µM to 600 µM, and from 1 mM to 10 mM with sensitivity equal to 987.85 mA cm-2mM−1 and 170.85 mA cm-2mM -1 respectively.