A novel electrochemical sensor via Zr-based metal organic framework–graphene for pesticide detection

Methyl parathion (MP), as a typical organophosphorus pesticide, has been widely used in pest control and plant growth regulation. Simultaneously, the problem of pesticide residues also poses a serious threat to the environment and human health. Currently, pesticide residue detection technology still faces great challenges in practical applications due to the problems of expensive facilities and complicated operations in conventional analysis methods. To address these problems, a novel nonenzymatic electrochemical pesticide sensor was reported. A zirconium-based metal organic framework material with terephthalic acid as a ligand (Zr-BDC) was designed to combine with electro-reduced graphene oxides (rGO). The Zr-BDC-rGO nanocomposite contains Zr-OH groups with high affinity for phosphate groups, endowing it with selective recognition and a higher adsorption capacity for MP. Moreover, rGO has a high specific surface area and excellent electron transport capability, making it an excellent functionalized adsorption and substrate material, which could improve the conductivity of the material and achieve a lower detection limit. Upon optimization, this sensor provided a wide linear range from 0.001 to 3.0 μg mL −1 and low limit of detection 0.5 ng mL −1 for MP. This work provides a rapid, sensitive and cost-effective sensing platform for pesticide residue detection. Graphical abstract