The integration of Mn and Co redox couples endowed MnCo2O4-modified electrochemical sensing platform for ultrasensitive detection of Carbendazim residue in fruit and vegetable samples

This study reports the carbendazim (CBZ) detecting capability of spinel cobaltite MnCo 2 O 4 (MCO) synthesized via a microwave-assisted hydrothermal approach. The MCO-modified screen-printed electrode (MCO/SPE) exhibited excellent electrocatalytic activity toward CBZ oxidation. As a result, the proposed sensor enables sensitive CBZ detection over two distinct linear ranges (0.05–5 μM and 25–500 μM), with a low detection limit of 0.02 μM and a high sensitivity of 6.46 μA μM −1  cm −2 . The enhanced sensing performance is attributed to the synergistic redox activity of Co 2+ /Co 3+ and Mn 2+ /Mn 3+ couples, which enhance both electrical conductivity and catalytic activity, together with the nanorod morphology that promotes efficient diffusion of CBZ molecules and electrolyte species. The applicability of the MCO/SPE was further validated through effective CBZ detection in fruit and vegetable samples as compared with the liquid chromatography–tandem mass spectrometry (LC-MS/MS) method, showing strong potential for food safety monitoring.