Fluorescence-Reporting-Guided Tumor Acidic Environment-Activated Triple Photodynamic, Chemodynamic, and Chemotherapeutic Reactions for Efficient Hepatocellular Carcinoma Cell Ablation.

Tumor acidic environment-activated combination therapy holds great promise to significantly decrease side effects, circumvent multiple drug resistance, and improve therapeutic outcomes for cancer treatment. Herein, Sorafenib/ZnPc(PS)4@FeIII-TA nanoparticles (SPFT) are designed with acid-environment turned-on fluorescence to report the activation of triple therapy including photodynamic, chemodynamic, and chemotherapy on hepatocellular carcinoma. The SPFT are composed of SP cores formulated via self-assembly of sorafenib and ZnPc(PS)4, with high drug loading efficiency, and FeIII-TA shells containing FeCl3 and tannic acid. Importantly, the nanoparticles suppress reactive oxygen species (ROS) generation of ZnPc(PS)4 due to their formation in nanoparticles, while assisting simultaneous uptake of the uploaded drugs in cancer cells. The tumor acidic environment initiates FeIII-TA decomposition and accelerates a chemodynamic reaction between FeII and H2O2 to generate toxic •OH. Then, the SP core is decomposed to separate ZnPc(PS)4 and sorafenib, which leads to fluorescence turning-on of ZnPc(PS)4, expedited photodynamic reactions, and burst release of sorafenib. Notably, SPFT shows low dark cytotoxicity to normal cells but exerts high potency on hepatocellular carcinoma cells under near-infrared light irradiation, which is much more potent than either sorafenib or ZnPc(PS)4 alone. This research offers a facile nanomedicine design strategy for cancer therapy.