▎ 摘　　要

NOVELTY - A magnetic graphene material is obtained by depositing ferrite-type magnetic nanoparticles on graphene. USE - Magnetic graphene material is used for detecting phthalate in food (claimed). ADVANTAGE - The magnetic graphene material has high phthalate-detecting efficiency. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) preparation of magnetic graphene material. Graphene oxide and sodium chloride are reacted under alkaline condition, to obtain surface carboxylated graphene oxide. Then, polyethyleneimine (PEI) and ethyl amine propyl carbodiimide are added to oxide and reacted, to obtain PEI-modified graphene oxide. Iron acetylacetonate, amine and diphenyl ether are mixed and reacted under protection of nitrogen, ethanol is added to precipitate and centrifuged, to obtain precipitate. Then, water, oleic acid and oleamide are added to the precipitate, ultrasonically-treated, centrifuged and supernatant fluid is removed, to obtain oil-soluble ferrite nanoparticles. The obtained nanoparticles are dissolved in dimercaptosuccinic acid solution, pH value of solution is adjusted to 7-8, washed using pure water and dried, to obtain dimercaptosuccinic acid-modified ferrite oxide nanoparticles. The dimercaptosuccinic acid-modified ferrite oxide nanoparticles are loaded to surface carboxylated graphene oxide, to obtain magnetic graphene material; and (2) usage method of magnetic graphene material for detecting phthalate, which involves mixing magnetic graphene material with sample rich in phthalate, eluting with organic solvent, and detecting phthalate using chromatography.