Synthesis and characterization of the core–shell magnetic molecularly imprinted polymers (Fe3O4@MIPs) adsorbents for effective extraction and determination of sulfonamides in the poultry feed

• Published in: Journal of Chromatography A Vol. 1245; pp. 8 - 16
• Main Authors: Kong, Xuan, Gao, Ruixia, He, Xiwen, Chen, Langxing, Zhang, Yukui
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 06.07.2012
• Subjects: adsorbents; Adsorption; ammonia; Animal Feed - analysis; Animals; Anti-Bacterial Agents - analysis; binding sites; chickens; chromatography; cross-linking reagents; drug residues; Drug Residues - analysis; Ducks; ethylene glycol; Ferrosoferric Oxide - chemistry; Food Contamination - analysis; Fourier transform infrared spectroscopy; Imprinted polymers; iron; Magnetic nanoparticles; magnetite; medicated feeds; Molecular Imprinting; Molecularly imprinted polymers (MIPs); nanoparticles; polymers; Polymers - chemical synthesis; Polymers - chemistry; Poultry; Poultry feed; scanning electron microscopes; Scanning electron microscopy; Selectivity; silica; Silicon dioxide; sol-gel processing; Solid Phase Extraction - instrumentation; Solid Phase Extraction - methods; Sulfonamide; sulfonamides; Sulfonamides - chemistry; Sulfonamides - isolation & purification; Surface chemistry; transmission electron microscopes; transmission electron microscopy; Poultry feed; Molecularly imprinted polymers (MIPs); Sulfonamide; Magnetic nanoparticles
• ISSN: 0021-9673; 1873-3778
• DOI: 10.1016/j.chroma.2012.04.061

► We present a general method to prepare the core–shell magnetic MIPs nanoparticles (Fe3O4@MIPs) for sulfamethazine. ► The Fe3O4@MIPs possess a highly improved imprinting factor, fast adsorption kinetics and high adsorption capacity. ► The structure and affinity properties of the resulting Fe3O4@MIPs were characterized. ► We used Fe3O4@MIPs for enrichment and determination of SMZ in the poultry feed samples. In this study, we present a general method to prepare the core–shell magnetic molecularly imprinted polymers (MIPs) nanoparticles (NPs) for sulfamethazine (SMZ). The resulting Fe3O4@MIPs NPs possess a highly improved imprinting effect, fast adsorption kinetics and high adsorption capacity, and can be applied to extract sulfonamide in the poultry feed. In this protocol, the magnetite NPs were synthesized by co-precipitating Fe2+ and Fe3+ in an ammonia solution first. Silica was then coated on the Fe3O4 NPs using a sol–gel method to obtain silica shell magnetic NPs. Subsequently, the vinyl groups were grated onto silica-modified Fe3O4 surface by 3-methacryloyloxypropyltrimethoxysilane. Finally, the MIPs films were formed on the surface of Fe3O4@SiO2 by the copolymerization of vinyl end groups with functional monomer, methacrylic acid, cross-linking agent, ethylene glycol dimethacrylate, the initiator azo-bis-isobutyronitrile and template molecule, sulfamethazine. The morphology, magnetic, adsorption and recognition properties of Fe3O4@MIPs NPs were characterized using transmission electron microscope (TEM), scanning electron microscope (SEM), Fourier transform infrared (FT-IR) spectrometer, vibrating sample magnetometer (VSM) and re-binding experiments. The results showed that the binding sites of Fe3O4@MIPs were good accessibility, fast adsorption rate and the maximum adsorption capacity of Fe3O4@MIPs to SMZ was 344.8μgg−1. The selectivity of the obtained Fe3O4@MIPs NPs were elucidated by the different rebinding capability of SMZ and structural related sulfonamides in the mixed solution. The results indicated that the Fe3O4@MIPs had high imprinting factor 9.5 and significant selectivity. A method was developed for enrichment and determination of SMZ in the poultry feed samples with recoveries of duck and chicken feed ranging from 63.3 to 76.5% and 68.7 to 74.7%, respectively and the relative standard deviations (RSD) (<6.7%).