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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]

In this study, a simple route for the synthesis of hollow mesoporous carbon materials (HMCMs) with adjustable shell thicknesses via a one-pot strategy for direct carbonization and etching was developed. HMCMs were examined as a carrier matrix for the delivery of tetracycline hydrochloride (TH). The thickness of the mesoporous shell could be tuned between 7 and 90 nm by changing the amount of cetyltrimethylammonium bromide and composition of the polymer precursor. The obtained materials were characterized by transmission electron microscopy, scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, and N adsorption-desorption isotherms. The optimum conditions for the synthesis of the HMCM spheres were systematically investigated. The synthesized materials possessed specific surface areas of 710-954 m g and average pore diameters of 3.8 nm. The performance of the HMCMs towards the delivery of TH was tested in vitro in an aqueous bath at 37 °C; the release of TH from these drug delivery systems was monitored by UV-Vis spectroscopy. Results demonstrated that by adjusting the mesoporous carbon shell thickness of the HMCMs, high TH adsorption capacities (722-850 mg g) and tunable higher drug releases ranging from 15 to 25 h and sustained lower drug releases over the subsequent ~30 h were achieved. [ABSTRACT FROM AUTHOR]