三聚氰胺磁性印迹固相萃取材料的制备及其应用

采用磁性氧化石墨烯(GO)为载体，三聚氰胺(MEL)为模板分子，甲基丙烯酸(MAA)为功能单体，乙二醇二甲基丙烯酸酯(EGDMA)为交联剂，制备了新型三聚氰胺磁性印迹聚合物。 采用扫描电子显微镜(SEM)、透射电子显微（TEM）、差热分析(TG)和样品振动磁强计(VSM)对该磁性印迹聚合物进行表征和分析，结果表明，在氧化石墨烯表面成功制备磁性印迹聚合物。 结合高效液相色谱分析技术对该印迹聚合物的吸附性能进行检测，结果表明，该磁性印迹聚合物对三聚氰胺表现出特异性吸附性能，最大吸附容量为33.11 mg/g；相对于环丙氨嗪和三聚氰酸，三聚氰胺的选择因子(β)分别是2.43和2.84。 结合磁固相萃取与液相色谱检测技术，实现了牛奶样品溶液中三聚氰胺的分离、富集和检测。

Preparation and Application of Melamine Magnetic Molecularly Imprinted Solid Phase Extraction Material

A novel melamine magnetic molecularly imprinted polymer(Fe3O4-GO@SiO2@MIP) was prepared based on graphene oxide(GO) using melamine(MEL) as the template molecule, methacrylic acid(MAA) as the functional monomer and ethylene glycol dimethacrylate(EGDMA) as the cross-linker. The Fe3O4-GO@SiO2@MIP was characterized by scanning electron microscope(SEM), transmission electron microscope(TEM), thermogravimetric analysis(TGA) and vibrating sample magnetometer(VSM). The results showed that MEL imprinted layer was grafted on magnetic GO surface successfully. The adsorption properties were investigated by high performance liquid chromatography, and the results demonstrated that the Fe3O4-GO@SiO2@MIP exhibited specific selectivity towards MEL. The maximum adsorption capacity of Fe3O4-GO@SiO2@MIP is 33.11 mg/g, and the selectivity factor of MEL towards CYR and CYA is 2.43 and 2.84, respectively. Combined with magnetic solid phase extraction(M-SPE) and high-performance liquid chromatography with the imprinted material as stationary phase, melamine from the sample solution of milk was successfully separated, enriched and detected.