▎ 摘　　要

NOVELTY - A magnetic resonance imaging contrast agent based on nano graphene oxide comprises gadolinium(Gd3+)ion type magnetic resonance imaging nano contrast agent pGO-Gd, and gadolinium(Gd3+)ion and branched-chain type polyethylene glycol functional nano graphene oxide(pGO) magnetic resonance imaging contrast agent pGO-Gd. USE - Magnetic resonance imaging contrast agent based on nano graphene oxide used for vivo blood vessel, tumor, lymph node and organ image preparation through vein injection (all claimed) and skin injection. ADVANTAGE - The agent has simple preparation, high magnetic relaxation rate, good conversion, dispersibility and compatibility, and long imaging time window. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of magnetic resonance imaging contrast agent based on nano graphene oxide comprising adding natural graphite powder as raw material with sodium chloride, magnetic force stirring concentrated sulfuric acid and sodium nitrate, adding potassium permanganate, continuously stirring, controlling temperature at room temperature, stirring, reacting at 95 degrees C, adding hydrogen peroxide, termination reacting, washing using dilute hydrochloric acid and deionized water, centrifuging to obtain nano graphene oxide, dispersing into water, regulating concentration, adding N-hydroxysuccinimide (NHS) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), stirring, regulating pH value to 4-7, adding branched-chain type polyethylene glycol as amine solution, stirring and reacting at low temperature, diluting with deionized water, washing by ultrafilter centrifuge at 10-100 KDa molecular weight cut-off to obtain functional nano graphene oxide pGO, dispersing into water, regulating concentration, adding gadolinium ion solution, stirring overnight, diluting with deionized water, washing by ultrafilter centrifuge at 1-100 KPa molecular weight cut-off, and dispersing into water.