Preparation And Application Of Magnetic Molecularly Imprinted Polymer For Sulfonamides

Sulfonamides?SAs?are a widely used antibacterial drug,which are commonly used in breeding industry.Due to the high water solubility and-low binding constants,most of the used SAs are not metabolized,which could be easy to migrate into the environment with animal feces and urine.The resistance of microorganisms resulted from the SAs residues could bring the drug resistance genes to the next generation or other biological bacteria trough the breeding or genetic drift,and then make threat to human by the food chain.However,according to the low abundance and enormous interferences in environment,it is urgent to develop a rapid enrichment method for SAs.Molecularly imprinted polymers with high specificity and selectivity have been widely used in the pretreatment process of pollutants.Up to now,with the magnetic separation characteristics,magnetic molecularly imprinted polymers have been applied into the quick separation of samples.In this study,a kind of core-shell magnetic molecularly imprinted polymers?Fe₃O₄@MIPs?with specific selectivity for sulfonamides,was prepared by precipitation polymerization.The Fe₃O₄@MIPs were synthesized on the surface of Fe₃O₄@Si O2 by the copolymerization of vinyl end groups using sulfanilamide as a dummy template based on the principle of epitope,MAA as the functional monomer,EDMA as cross-linking agent,AIBN as the initiator.Compared with previous research,this kind of Fe₃O₄@MIPs possessed the core-shell structure,leading to a faster transfer rate and adsorption kinetics process.Fe₃O₄@MIPs were firstly characterized by FT-IR,SEM and specific surface area and so on.And results showed that Fe₃O₄@MIPs had the core-shell structure with a size at 500-1000 nm.Fe₃O₄@MIPs performed the best –adsorption ability using water as the adsorption system,with the best p H range between 4 to10.Because Fe₃O₄@MIPs had a thin imprinted layer,After 7 times of ultrasonic extractions,the template molecule could be completely eluted from Fe₃O₄@MIPs.The adsorption equilibration of Fe₃O₄@MIPs could achieve only in 10 min,and the theoretical maximum adsorption amount wad 8.46 mg/g.After 5 times of adsorption and regeneration,the adsorption loss rate of Fe₃O₄@MIPs was only 18%,suggesting that the Fe₃O₄@MIPs had a good reusability.Besides,Fe₃O₄@MIPs performed well when using other SAs as the separation targets.Finally,river water was used as sample,and the recoveries of Fe₃O₄@MIPs ranged from 79.3% to 92.6%,with the relative standard deviation?RSD?at 0.9% to 7.3%.Thus,the prepared Fe₃O₄@MIPs could be applied to the enrichment and separation of the SAs from environmental samples.