Development of MWCNT/Co3O4 Nanocomposite-Based Electrodes for Electrochemical Sensing of Ascorbic Acid

Ascorbic acid (AA), popularly known as Vitamin C, is a biomolecule essential for tissue repair, enzyme generation and immune system regulation. While the natural sources of AA are citrus fruits and vegetables, it is also available in the form of dietary supplement and topical serums. Due to the manifold functions and applications of AA in human physiology, it becomes necessary to monitor the AA level in real samples. Other than the traditional approaches, the recent research are targeted on the development of smart electrodes for quick and accurate electrochemical sensing of AA. In the present study, electrodes based on cobalt oxide (Co3O4) hybridized with multi-walled carbon nanotube (MWCNT) have been developed. The Co3O4 nanoparticles have been synthesized via a facile and rapid microwave synthesis method. These were further doped with lithium and blended with MWCNT for achieving high electrochemical activity. The cyclic voltammetry and chronoamperometry studies exhibited a positive outcome for the detection of AA with a limit of detection (LOD) value of 0.55 mM. The quick detection of AA through amperometry is an important achievement and reveals the synergistic activity of CNT/metal oxide-based hybrid electrodes for developing future high-sensitive electrochemical sensors.