4-in-1 Fe3O4/g-C3N4@PPy-DOX nanocomposites: Magnetic targeting guided trimode combinatorial chemotherapy/PDT/PTT for cancer

At present, cancer has become a major disease threatening human health worldwide. Therefore, developing targeting guided multimode synergetic therapy has become one of the hot spots in current antitumor research and is also a great challenge. Herein, a new Fe3O4/g-C3N4@PPy-DOX nanocomposite containing magnetic iron oxide (Fe3O4) nanoparticles (NPs), lamellar structure of graphite-like carbon nitride (g-C3N4) and polypyrrole (PPy) shell with the loaded anti-tumor drug doxorubicin hydrochloride (DOX) was designed and prepared. The monodisperse Fe3O4 nanoparticles (NPs) with the diameter of 20 nm endowed the nanocomposite with the magnetic targeting ability, reducing damage to normal tissues. It is very interesting that the Fe3O4 NPs also possessed photosensitizer function for photodynamic therapy (PDT). The g-C3N4 sheets as the photocatalysis towards the degradation of water for generating O-2 could effectively improve the hypoxia of solid tumors and increase the efficiency of PDT. In addition, PPy has high light-to-heat conversion efficiency, so was chosen for the cancer photothermal therapy (PTT). Finally, an anticancer drug (DOX) was loaded on the nanocomposite because the presence of mesoporous structure. Thus, the prepared Fe3O4/g-C3N4@PPy-DOX nanocomposites exhibit synergetic chemotherapy/PTT/enhanced PDT antitumor effect. This study provides an inspiration for combining targeting and multimodality to improve the anticancer efficiency.