GRAPHENE QUANTUM DOT-GADOLINIUM ION CHELATE MAGNETIC RESONANCE CONTRAST AGENT AND PREPARATION METHOD THEREFOR

摘要

A graphene quantum dot-gadolinium ion chelate (Gd@GQDs), relating to the field of nanomaterials. The graphene quantum dot-gadolinium ion chelate is a nanomaterial, whereof the surface has hydrophilic groups, and the preparation method therefor comprises: preparing graphene oxide by using a Hummers method; next, performing heating, oxidation, and purification to obtain pure graphene quantum dots; and finally, chelating the graphene quantum dots with Gd³⁺ to form stable Gd@GQDs. The Gd@GQDs are easy to disperse in water or a aqueous system such as a phosphate buffer solution (PBS) and a biological medium, have good biocompatibility and low toxicity, show an excellent T₁ weighted contrast performance in a 1.5 T magnetic resonance test system, and have an r₁ relaxation rate as high as 72 mM^-1s^-1, the value of r₁ being 20 times higher than the current commercial T₁ weighted magnetic resonance contrast agent Gd-DTPA.