MOFs-Derived Fe–N Codoped Carbon Nanoparticles as O2-Evolving Reactor and ROS Generator for CDT/PDT/PTT Synergistic Treatment of Tumors

Metal–organic frameworks (MOFs) derivatives had been widely explored in electronic and environmental fields, but rarely evaluated in the biomedical applications. Herein, Fe–N codoped carbon (FeNC) nanoparticles were synthesized and characterized via facile pyrolysis of precursor ZIF-8 (Fe/Zn) nanoparticles, and their potential applications in tumor therapy were assessed in this investigation both in vitro and in vivo. After PAA (sodium polyacrylate) modification, the FeNC@PAA nanoparticles were able to initiate a Fe-based Fenton-like reaction to generate ·OH and O2 for chemodynamic therapy (CDT) and O2 evolution. Meanwhile, the porphyrin-like metal center in the FeNC@PAA nanoparticles could be used as a photosensitizer for photodynamic therapy (PDT) of tumors, which could be enhanced by O2 generated in CDT. Furthermore, the FeNC@PAA nanoparticles were also found to be effective in photothermal therapy (PTT) with a photothermal conversion efficiency of 29.15%, owing to a high absorbance in the near-infrared region (NIR). In conclusion, the synthesized FeNC@PAA nanoparticles exhibited promising applications in O2 evolution and CDT/PDT/PTT synergistic treatment of tumors.