Sensitive and selective non-enzymatic detection of glucose by monodispersed NiO @ S-doped hollow carbon sphere hybrid nanostructures.

Development of selective, sensitive and non-enzymatic sensor for glucose determination is highly important for the diagnosis and management of diabetes. Herein, we have reported the novel ultra sensitive and non-enzymatic sensor development by in-situ wraped NiO nanostructures (∼10-15 nm) on the sulfur-doped hollow carbon nanospheres (SDHCNSs) through hydrothermal-assisted process. The structural and morphological properties of the nanocomposites were characterized by X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) techniques. The prepared NiO@SDHCNSs was directly used as an electrochemical sensor for glucose determination, and its performance was evaluated by cyclic voltammetry and amperometric techniques. The fabricated non-enzymatic biosensor was exhibited remarkably good sensitivity (1697 μA mM-1cm-2), low detection limit (LOD) (52 nM), a wide linear range (up to 13 mM) of glucose with desirable selectivity, stability and reproducibility. Further, the constructed sensor has demonstrated an excellent anti-interference property in the presence of common interferences such as dopamine (DA), uric acid (UA) and ascorbic acid (AA). Most interestingly, the fabricated electrode is applicable for the practical analysis of glucose in the real blood serum and urine samples. The excellent electrochemical performances of NiO@SDHCNSs towards the oxidation of glucose are attributed to the increased electron transfer passage through unique hollow spherical morphology with increased redox couple of Ni(OH)2/NiOOH derived from NiO. Thus, the improved electrochemical performances of NiO@SDHCNSs can be adopted as a potential electrode for the real sample analysis.