Preparation And Application Research Of Molecularly Imprinted Polymers Of The Sterigmatocystin

Sterigmatocystin?ST?is secondary metabolites which are produced by Aspergillus flavus,Aspergillus nidulans and other fungi.It can mostly contaminate grain and fodder.ST has an extreme toxicity just next to Aflatoxin.As a result,ST has a serious threat for human and animal life.Therefore,the establishment of ST detection method has an important significance.In the paper,two types of molecularly imprinted polymers were prepared,which have high adsorptive selectivity to ST.Molecular imprinted polymers as solid phase extraction material coupled with high performance liquid chromatography,the ST detection method was established and used for the actual sample detection.?1?1,8-dihydroxyanthraquinone?DT?has a similar structure with ST for its low toxicity,low cost and market commercialization used as an alternative template,AM as functional monomer,EGDMA as crosslinker,AIBN as initiator,molecularly imprinted polymer materials?MIPs?was prepared using a bulk polymerization successfully.The material is characterized using infrared spectroscopy,scanning electron microscopy techniques.To verify the adsorption properties of MIPs,adsorption experiments?including adsorption kinetics experiment,equilibrium adsorption experiments and selective adsorption experiments?were processed,and the results showed that MIPs has a higher selection adsorption to ST and adsorption capacity to ST was 3.99 mg g'1.MIPs as the solid phase extraction material,the best conditions for SPE were optimized including the type of sample solvent,eluent composition,elution volume and other conditions.The SPE coupled with HPLC method was established to detect ST residues in food.?2?Fe₃O₄ NPs was synthesized by hydrothermal as a support carrier and the core-shell structure magnetic Fe₃O₄@MIPs was prepared by precipitation polymerization,and was characterized by infrared spectroscopy,scanning electron microscopy,VSM and a series of adsorption experiments to verify the adsorption ability of Fe₃O₄@MIPs.The results showed that the magnetic imprinted polymers have a higher selective adsorption to ST and the adsorption capacity of ST was 3.98 mg g^-1.The method using magnetic solid phase extraction associated with HPLC was established to detect the ST content in the sample.To verify the feasibility of the two established methods,three blank samples of rice,wheat,millet were spiked at three levels with 50,100,200 p.g kg^-1 to calculate the spiked recovery.The results showed an average recovery between 80.6%-88.7%and the relative standard deviation?RSD?was between 0.4%-5.6%by MIP-SPE-HPLC.The average recovery was between 81.2.6%-85.3%and RSD was between 0.7%-5.5%by MMIP-MSPE-HPLC.In a consequence,it is proved that the analytical method is accurate and feasible.