A nonenzymatic electrochemical glucose sensor depending on a NiNPs/Co₃O₄/functionalized graphene oxide-modified...

In the present research, the aim was to develop a novel electrochemical enzyme-free glucose sensor dependent upon a nickel nanoparticles (NiNPs)/cobalt (II, III) oxide (Co₃O₄)/carboxylated graphene oxide (GO-COOH)-modified glassy carbon (GC) electrode. The electrocatalytic performance of the electrode was tested using various electrochemical methods such as amperometry and cyclic voltammetry (CV). The NiNPs@Co₃O₄/GO-COOH/GC electrode showed noticeably superior electrocatalytic behavior for glucose oxidation in 0.1 M NaOH media, ascribed to the good synergistic impact between NiNPs, Co₃O₄, and GO-COOH. The amperometric response of the NiNPs@Co₃O₄/GO-COOH/GC electrode to glucose exhibited two linear determination ranges at +0.55 V potential. The first one was between 4.8 × 10^-7 and 9.5 × 10^-4 M and the second one was between 9.5 × 10^-4 and 4.87 × 10^-3 M. The limit of detection was 1.4 × 10^-7 M dependent upon a signal-to-noise ratio of 3. The sensor displayed good performance factors such as selectivity, reproducibility, and stability. Furthermore, the suitability of the sensor for detecting glucose in biological fluids proved satisfactory.