Preparation And Application Of Surface Molecular Imprinted Polymer Of Sulfadimethoxine

With the improvement of the living standards of our people and the rapid development of animal husbandry,people’s demands for animal-derived foods no longer stay in the pursuit of quantity,instead,customers hope to obtain high quality,safe products.In recent years,due to the severe animal disease prevention and control situation at home and abroad,the abuse of antibacterial drugs to animal in China has be continued,causing potential harm to human health and the environment.Among these antibacterial drugs,sulfa antibiotics,which are cheap,efficient in prevention,cure and production promotion,have become one of the varieties of veterinary drugs that are easily abused.The detection of veterinary drug residues is the last line of defense before animal-derived foods enter thousands of households.The composition of animal-derived foods is complex,so it is necessary to find sensitive and efficient detection methods.In this experiment,Sulfadimethoxine was used as a template molecule to prepare a surface molecularly imprinted polymer on the surface of microsilica gel by atom transfer radical polymerization,which was expected to use as a specific extractant for matrix dispersion solid phase extraction.With chromatography,it was used to establish an analytical method for the determination of Sulfadimethoxine residues in pork samples.The prepared surface molecularly imprinted polymer were characterized by scanning electron microscopy,infrared spectroscopy,elemental analysis and thermos-gravimetric analysis to confirm the structural characteristics of the molecularly imprinted polymer.At the same time,the static adsorption test was used to investigate the kinetic behavior,isothermal adsorption curve and adsorption selectivity of the molecularly imprinted polymer.The prepared microspheres were then used as matrix extractant for solid phase dispersion extraction in the pretreatment of pork samples,and high performance liquid chromatography was used to detect the residues of Sulfadimethoxine in pork.Through structural characterization,it was confirmed that the molecular imprinted layer had been formed on the surface of the silica microspheres.Through the study of adsorption kinetics,isothermal adsorption curve and selective adsorption,it is proved that the prepared molecularly imprinted polymer has faster adsorption rate and reaches the adsorption equilibrium at 1.5 h.The adsorption amount is high and exhibits better adsorption specificity performance than non-molecularly imprinted polymer.A sample pretreatment method was established by using the molecularly imprinted polymer as an extractant for matrix dispersion solid phase extraction.The final recovery rate of pork samples was 65%-85%,and the RSD was about 5%.The precision RSD is less than 7%,the detection limit of the method is 10 μg/kg,and the limit of quantification is 30 μg/kg.In summary,this paper established a drug residue analysis method for the detection of Sulfadimethoxine residues in pork,which lays a theoretical and practical foundation for the efficient detection of sulfonamide residues in meat samples and the application of surface molecular imprinting techniques.