Preparation and evaluation of superparamagnetic core-shell dummy molecularly imprinted polymer for recognition and extraction of organophosphorus pesticide.

In this paper, we reported a simple and effective strategy to synthesize core-shell dummy template magnetic molecularly imprinted polymers (FeO@DMIPs) using ethyl paraoxon as a template for the recognition and selective extraction of organophosphorus pesticide. Initially, monodisperse FeO nanoparticles were synthesized directly through a facile one-pot hydrothermal method. Then, the imprinted layer was synthesized directly on the surface of the magnetic core by means of a one-pot sol-gel copolymerization which avoided further modification of the external part of the magnetic core. The structure and morphology of the materials (FeO@DMIPs) were characterized by SEM, TEM, FTIR, XRD, and VSM. It was observed that FeO@DMIPs showed regular morphology, good dispersibility, and superparamagnetism. The synthesis conditions for the formation of FeO@DMIPs were systematically investigated. It was found that the morphology and monodispersity of FeO@DMIPs were highly influenced by the ratio of the mixture solvent of methanol and water and the volume ratio of functional monomer (APTES) and cross-linker (TEOS). The binding performance of the imprinted polymers was investigated through a series of adsorption experiments, which indicated that the FeO@DMIPs had a fast adsorption rate (15 min) and high adsorption capacity (195.7 mg g) to methyl parathion and phoxim. Meanwhile, real wine sample tests demonstrated a good extraction effect. This study provides a possibility for the selective extraction of organophosphorus pesticide residue in a complex matrix. [ABSTRACT FROM AUTHOR]