The preparation and drug delivery of a graphene-carbon nanotube-Fe ₃O₄ nanoparticle hybrid

We report a green and facile procedure of synthesizing a graphene nanosheet-carbon nanotube-iron oxide nanoparticle hybrid (GN-CNT-Fe ₃O₄) as a promising platform for the loading and delivery of anticancer drugs. The obtained GN-CNT-Fe₃O₄ hybrid exhibited superparamagnetic properties with the saturation magnetization of 19.824 emu g^-1. This hybrid nanostructure possesses a superior capability of binding the anticancer drug 5-fluorouracil (5-FU) with a high loading capacity of up to 0.27 mg mg^-1 with a 5-FU concentration of 0.5 mg mL^-1, and also possesses a pH-activated release profile. Moreover, cellular uptake studies show that the resulting GN-CNT-Fe ₃O₄ hybrid can be internalized efficiently by HepG2 cells. In vitro cytotoxicity tests suggest that the obtained GN-CNT-Fe ₃O₄ hybrid is nontoxic for Chang liver cells, even at the high concentration of 80 μg mL^-1, however, the 5-FU-loaded GN-CNT-Fe₃O₄ hybrid showed significant cytotoxic effects in HepG2 cells. The results show that this novel 3D hybrid is a promising candidate for anti-cancer drug delivery systems.