A novel multi-stimuli-responsive theranostic nanomedicine was designed and fabricated by the conjugation of a thiol end-capped poly(N-isopropylacrylamide-block-acrylic acid) (HS-PNIPAAm-b-PAA) onto Fe3O4@Au nanoparticles (NPs) followed by physical loading of doxorubicin hydrochloride (Dox) as a general anticancer drug. For this purpose, Fe3O4@Au NPs were fabricated through small Au nanolayer grown on larger magnetic NPs. A HS-PNIPAAm-b-PAA was synthesized through an atom transfer radical polymerization (ATRP) approach, and then conjugated with as-synthesized Fe3O4@Au NPs by Au-S bonding. The Dox loading capacity of the synthesized Fe3O4@Au/Polymer theranostic NPs was calculated to be 81%. The theranostic nanomedicine exhibited excellent in vitro drug release behavior under pH and thermal stimuli. The anticancer activity evaluation using MTT assay (against MCF7 cells) revealed that the fabricated Fe3O4@Au/Polymer has high potential as theranostic nanomedicine for cancer therapy of solid tumors. This nanosystem can also applied in photothermal therapy, hyperthermia therapy, and their combination with chemotherapy due to presence of gold and Fe3O4 nanomaterials in its structure.
Keywords: Cancer; Fe3O4@Au nanoparticles; chemotherapy; stimuli-responsive; theranostic nanomedicine.