Development And Application Of A New Type Of Magnetic Composites Blot

In this paper, magnetic molecularly imprinted polymers (MIPs) based on Fe4O3were prepared by sol-gel or thermal polymerization method with surface imprintingtechnique. And these polymers were successfully used in the separation of food additiveand natural product.1. Rhein magnetic molecularly imprinted polymer (Fe3O4@SiO2@MIP) wasprepared based on the magnetic particles by using rhein as the template molecule,phenyl and amino group silane agent as binary functional monomer and tetraethylorthosilicate (TEOS) as cross-linking agent. The Fe3O4@SiO2@MIP was characterizedby scanning electron microscope (SEM). The results showed that the rhein imprintedlayer has been grafted on magnetic particles surface successfully. TheFe3O4@SiO2@MIP is uniform cube structure and the thickness of the imprinted shell isabout75~100nm. Combined with magnetic solid phase extraction (M-SPE) andhigh-performance liquid chromatography technology, the imprinted material employedas stationary phase was used to separate, enrich and detect rhein, emodin andchrysophanol from kiwi fruit root successfully.2. A novel melamine magnetic molecularly imprinted polymer（Fe3O4-GO@SiO2@MIP） was prepared based on graphene oxide (GO) by usingmelamine (MEL) as the template molecule, methacrylic acid (MAA) as the functionalmonomer and ethylene glycol dimethacrylate (EGDMA) as the cross-linker. TheFe3O4-GO@SiO2@MIP was characterized by scanning electron microscope (SEM)、transmission electron microscope (TEM)、 thermogravimetric analysis (TGA) andvibrating sample magnetometer (VSM). The results showed that MEL imprinted layerwas grafted on magnetic GO surface successfully. The adsorption properties wereinvestigated by high performance liquid chromatography, and the results demonstratedthat the Fe3O4-GO@SiO2@MIP exhibited specific selectivity towards MEL. Themaximum adsorption capacity of Fe3O4-GO@SiO2@MIP was33.11mg g-1, and theselectivity factor of MEL towards CYR and CYA was2.43and2.84, respectively.Combined with magnetic solid phase extraction (M-SPE) and high-performance liquidchromatography technology, the imprinted material employed as stationary phase wasused to separate, enrich and detect melamine from sample solution of milk successfully.3. Magnetic molecularly imprinted polymer（Fe3O4@SiO2@MIP）was prepared byusing magnetic iron oxide as the carrier, curcumin as the template molecule,methacrylic acid (MAA) as the functional monomer and ethylene glycol dimethacrylate(EGDMA) as the cross-linker. The Fe3O4@SiO2@MIP was characterized by scanningelectron microscope (SEM)、 thermogravimetric analysis (TG)、 vibrating sample magnetometer (VSM) and infrared spectroscopy (IR). The results showed that themolecularly imprinted polymer was prepared successfully on magnetic iron oxidesurface. The adsorption properties were investigated by high performance liquidchromatography (HPLC), and the results demonstrated that the Fe3O4@SiO2@MIPexhibited specific selectivity towards curcumin. The maximum adsorption capacity ofFe3O4@SiO2@MIP was36.2mg g-1, and the selectivity factor of curcumin towardsrhein and emodin was2.0and2.2, respectively. Combined with magnetic solid phaseextraction (M-SPE) and high-performance liquid chromatography technology (HPLC),the imprinted material employed as stationary phase entraction material was used toseparate, enrich and detect curcumin in ginger powder sample solution successfully.