Electrochemical non-enzymatic glucose sensors based on nano-composite of Co3O4 and multiwalled carbon nanotube

Nanocomposite of Co₃O₄ and multiwalled carbon nanotube (MCNT) was synthesised using one step solvothermal method, and an electrochemical non-enzymatic glucose sensor (Co₃O₄-MCNT/GCE) was successfully constructed by a dropping method. The obtained Co₃O₄ and Co₃O_4^- MCNT were characterized and investigated by transmission electron microscopy (TEM) and energy dispersive Xray spectroscopy (EDS). Quantitative analysis of glucose was performed using the amperometric (i-t) method, and plot of current difference versus concentration of glucose was linear in the range of 1.0-122 μmol/L, with a linear correlation coefficient (R²) of 0.9983 and limit of detection (LOD) of 0.28 μmol/L. Sensitivity of this sensor was evaluated as 2550 μA L mmol^-1 cm^-2. This new sensor produced satisfactory reproducibility and stability and was applied to monitor trace amounts of glucose in human serum samples.