Multifunctional integration of biomass-derived porous carbon and zirconium dioxide for electrochemical sensing analysis of methyl parathion

We developed an economical and environment-friendly technique for preparing the expired mung bean-derived porous carbon (EMBPC), which possessed large specific surface area and 3D interlinked carbon conductive network. Zirconium dioxide (ZrO 2 ) nanoparticles were further incorporated into the porous structure of EMBPC to form the EMBPC@ZrO 2 composite, which was served as electrode sensitizer for the fabrication of EMBPC@ZrO 2 /GCE sensor. EMBPC exhibited superior conductivity property and large electroactive area, which helped enhance the charge transfer efficiency between electrolyte and sensing electrode. ZrO 2 nanoparticles with good biocompatibility achieved the efficient adsorption of methyl parathion (MP) owing to the recognition of ZrO 2 towards the phosphate groups of MP. Furthermore, EMBPC with porous carbon conductive structure could make up for the inherent disadvantage of ZrO 2 nanoparticles in the term of electrical conductivity. The EMBPC@ZrO 2 /GCE sensor achieved the highly sensitive MP detection (LOD: 8.77 nM) in linear MP concentration range of 0.01–10 μM. The satisfactory practical property was realized at the EMBPC@ZrO 2 /GCE sensor with satisfactory recovery rates of 91.95–124.72% and low RSD% of 1.21–3.35% for the electrochemical detection of MP in food samples.