Non-enzymatic electrochemical detection of caffeic acid in food samples with spinel magnesium cobalt oxide incorporated graphene nanohybrid electrocatalyst

Caffeic acid (CA) is one of the significant polyphenolic compounds primarily used as an antioxidant and medicine. The extensive usage of CA increases toxicity and affects health. Consequently, we have prepared an electrochemical sensor based on spinel magnesium cobalt oxide (MCO) with graphene (GR) sheets derived electrocatalyst (MCO/GR) for the rapid detection of CA. The elemental, and structural details were investigated with several spectroscopic techniques. The electrocatalytic behavior towards the CA was estimated with different voltammetric methods. Our MCO/GR-based electrochemical sensor demonstrated a low detection limit (0.003 µM), optimal sensitivity (1.494 µA µM^–1 cm^–2), low limit of quantification (0.013 µM), and good linear ranges (0.01 µM to 0.69 µM and 0.69 µM to 447.19 µM). This sensor showed good electrochemical performance and was applied to monitor CA in various food samples and obtained remarkable recoveries. Based on these results, our MCO/GR sensor is a promising electrochemical platform for determining CA.