Modification of graphene oxide by a facile coprecipitation method and click chemistry for use as a drug carrier†
A ternary composite based on graphene oxide (GO), Fe3O4 nanoparticles and poly[2-(dimethylamino) ethyl methacrylate] (PDMAEMA) was synthesized via anchoring Fe3O4 nanoparticles onto a GO nanosheet by a facile coprecipitation method and subsequently grafting PDMAEMA to the surface by click chemistry. It was shown that the composite had a defined structure and morphology. Thermogravimetric analysis (TGA) results showed that the weight ratio of attached Fe3O4 nanoparticles was above 10.86 wt% and the surface grafting density reached above 2 chains per 10 000 carbon atoms of GO sheet. The composite exhibited good water dispersive stability depending on surface grafting density and grafted chain length. Loading and release behaviours of levofloxacin (LOFX) demonstrated that the composites had high loading capacity and pH triggered controlled release properties.