Synthesis and characterization of magnetic polymeric nanocomposites for pH-sensitive controlled release of methotrexate.

As one of the well-known anticancer drugs, methotrexate (MTX) has been limited in clinical application due to its side effects on normal tissues. This study focused on the one-step hydrothermal synthesis and in vitro evaluation of Fe3O4/RGO-PEI as MTX carriers for targeted anticancer therapy. In which, the Fe3O4 provided magnetic response properties; RGO acted as a stage for Fe3O4 loading and improved the dispersion of Fe3O4; polyethylenimine (PEI) was used as a surface modifier and a storehouse for MTX. The prepared Fe3O4/RGO-PEI nanocomposites exhibited a suitable size, good stability and magnetic responsibility. And the MTX loading content and loading efficiency were calculated to be 26.6% and 90.5%, respectively. What's more, due to the diffusion and dissolution of PEI, the Fe3O4/RGO-PEI-MTX exhibited excellent pH-sensitivity, the values of MTX release rate (%) within 48 h at pH 5.8 and 4.0 were 64.3% and 87.4%, respectively. Furthermore, MTT assays in cancer cells (HepG2) and normal cells (HUVEC) demonstrated that Fe3O4/RGO-PEI-MTX exhibited high anticancer activity while low toxicity to normal cells, and also the Fe3O4/RGO-PEI composites were practically non-toxic. Thus, our results revealed that Fe3O4/RGO-PEI-MTX would be a competitive candidate for targeted delivery and controlled release of MTX.