Polymer grafted magnetic graphene oxide as a potential nanocarrier for pH-responsive delivery of sparingly soluble quercetin against breast cancer cells.

In this work, polymer grafted magnetic graphene oxide (GO-PVP-Fe 3 O 4 ) was successfully synthesized for efficient delivery of anticancer drug. Firstly, GO was functionalized with the hydrophilic and biocompatible polymer polyvinylpyrrolidone (PVP) and then grafted with magnetic nanoparticles (Fe 3 O 4 ) through an easy and effective chemical co-precipitation method. Quercetin (QSR) as an anticancer drug was loaded onto the surface of GO-PVP-Fe 3 O 4 via non-covalent interactions. The drug loading capacity was as high as 1.69 mg mg -1 and the synthesized magnetic nanocarrier shows pH-responsive controlled release of QSR. The cellular cytotoxicity of the synthesized nanocarrier with and without drugs was investigated in human breast cancer MDA MB 231 cells and their effects compared on non-tumorigenic epithelial HEK 293T cells. These results reveal that the drug loaded GO-PVP-Fe 3 O 4 nanohybrid was found to be more toxic than the free drug towards MDA MB 231 cells and exhibits biocompatibility towards HEK 293T cells. Overall, a smart drug delivery system including polymer grafted magnetic graphene oxide as a pH-responsive potential nanocarrier could be beneficial for targeted drug delivery, controlled by an external magnetic field as an advancement in chemotherapy against cancer.