Adsorption and removal of organophosphorus pesticides from Chinese cabbages and green onions by using metal organic frameworks based on the mussel-inspired adhesive interface.

Based on the mussel-inspired adhesive interface (FeO-g-CN@PDA), a novel bionic metal-organic framework (FeO-g-CN-PDA@MIL-101) was successfully prepared. The composite featured a high specific surface area and a multi-microchannel structure, as well as strong thermochemical stability. The structural property of FeO-g-CN-PDA@MIL-101(Fe) was characterized, and the results indicated that FeO, PDA, and MIL-101(Fe) were uniformly coated on the g-CN surface. The adsorption and desorption of organophosphorus pesticides with FeO-g-CN-PDA@MIL-101(Fe) were evaluated by batch experiments. This composite showed high adsorption efficiency and selective removal of coralox, phosalone, and chlorpyrifos. Under the optimal conditions, three organophosphorus pesticides were adsorbed from Chinese cabbage and green onion samples with FeO-g-CN-PDA@MIL-101(Fe). The analytical method exhibited high sensitivity (LOD, 0.19-2.34 μg/L; LOQ, 0.65-7.82 μg/L), excellent practicality, and good stability, suggesting that FeO-g-CN-PDA@MIL-101 was an ideal candidate magnetic adsorbent for the removal of organophosphorus pesticides in Chinese cabbage and green onion samples.