Poly(deep eutectic solvent)@MOF-801 for technical surveillance of carbaryl: Pesticide residue safety control strategy

Carbamate pesticide residues in agricultural water and crops pose a significant threat to ecological safety and human health. In this research, a DES-mediated surface molecular imprinting strategy was developed to construct a high-performance adsorbent, PDES@MOF-801, for the selective removal of carbaryl from Poria cocos, a medicinal-food homologous crop. A zirconium-based MOF-801 was employed as the substrate, while a deep eutectic solvent (DES, choline chloride-acrylic acid, 1:2) was introduced as a functional monomer and transient structural regulator to guide imprinting-site formation. Density functional theory (DFT) calculations were integrated as a design-guiding tool to elucidate the formation, dissociation, and reconstruction of high-affinity recognition cavities at the molecular level. Adsorption experiments demonstrated that PDES@MOF-801 exhibited a high adsorption capacity (30.33 mg/g), a favorable imprinting factor (2.83), and stable performance over five reuse cycles. In practical sample analysis, the material achieved efficient removal of carbaryl from Poria cocos, with recoveries of 99.4-105.8%, a detection limit of 0.056 mg/L, and a quantification limit of 0.188 mg/L. Overall, this work establishes a mechanistically informed and efficient imprinting strategy for carbamate pesticide removal, providing a sustainable solution for pesticide residue monitoring, pollutant control, and agricultural quality management.