▎ 摘　　要

We report a facile approach to synthesize water-dispersible nanocomposite with Fe3O4 nanoparticles (NPs) attached to graphene (G), which combines the growth of Fe(3)O(4)NPs and the reduction of graphene oxide (GO) in one single step. The unique hydrophilic surface structure of Fe3O4/G nanocomposite leads to it being colloidally stable, non-cytotoxic, well-dispersible and biocompatible in aqueous solution verified via bio-experiments. In vivo tests also prove that Fe3O4/G nanocomposite, which can be cleared from the body through the metabolic processes, is harmless to the living body. Most importantly, the Fe3O4/G nanocomposite showed T-2 relaxivity (123.04 mM(-1) s(-1)) indicating its potential as a sensitive T-2 contrast agent. (C) 2016 Published by Elsevier B.V.