Preparation and application of Fe-Gd double-mode magnetic resonance contrast agent with targeting function

The invention relates to preparation and an application of a targeted nano contrast material, in particular to preparation and an application of a Fe-Gd double-mode magnetic resonance contrast agent with a targeting function. The existing clinic magnetic resonance contrast agent has the defects of no targeting and incapacity of enabling the contrast material to access into tumor cells accurately so as not to distinguish the normal tissues from the tumor tissues. The invention adopts the method that amino groups are coupled with active groups so as to enable the water-soluble Fe3O4 to have T1 and T2 double-mode imaging and targeting functions, and can realize specificity identification for tumor cells and tissues by targeted moleculars. The invention has the advantages of simple preparation method, accurate tumor diagnosis and wide applications in fields of medicine and biology, and the contrast agent has the T1 and T2 double-mode magnetic resonance imaging and targeting functions.