pH and Thermal Dual-Responsive Graphene Oxide Nanocomplexes for Targeted Drug Delivery and Photothermal-Chemo/Photodynamic Synergetic Therapy

The development of versatile nanoplatforms with efficient tumor-targeting properties and synergistic therapeutic strategies to realize effective antitumor efficiency are highly anticipated in the field of cancer therapy. Herein, we innovatively synthesized targeted nanocomplexes (NCGO-FA) with nanoscale structures by a modified Hummers' method and then used these nanocomplexes to separately load the doxorubicin (DOX) and methylene blue (MB) via pi-pi stacking, electrostatic attractions, and/or hydrophobic interactions, forming NCGO@DOX-FA and NCGO@MB-FA nanoplatforms. The results demonstrated that the NCGO-FA nanocomplexes have an ultrahigh surface area, a high-load content of drugs, targeting specificity, and a good photothermal conversion efficiency and photostability. Meanwhile, after loading the nanoplatforms with DOX or MB, NCGO-FA delivered drugs into cancer cells by folic acid (FA) receptors and triggered the drug release by heat and in acidic tumor environments. More importantly, compared with individually applied photothermal therapy, photodynamic therapy, or chemotherapy, the photothermal-chemo or photothermal-photodynamic synergistic therapy with the NCGO@ DOX-FA or NCGO@MB-FA nanoplatform exhibits a remarkable synergistic effect, resulting in a distinguished antitumor efficiency. Consequently, this work proposes a facile and versatile method to construct a dual-responsive versatile nanoplatform that combines photothermal-chemo and photodynamic therapies, and these nanoplatforms have excellent application prospects for tumor therapy.