Photothermal-reinforced and glutathione-triggered in Situ cascaded nanocatalytic therapy

Tumor microenvironment (TME)-responsive nanoformulations that catalyze a cascade of intracellular redox reactions showed promise for tumor treatment with high specificity and efficiency. In this study, we report Cu2+-doped zeolitic imidazolate frameworks-coated polydopamine nanoparticles (PDA@Cu/ZIF-8 NPs) for glutathione-triggered and photothermal-reinforced sequential catalytic therapy against breast cancer. In the TME, the PDA@Cu/ZIF-8 NPs could initially react with antioxidant glutathione (GSH), inducing GSH depletion and Cu+ generation. Whereafter, the generated Cu+ would catalyze local H2O2 to produce highly toxic hydroxyl radicals (center dot OH) through an efficient Fenton-like reaction even in weakly acidity. Importantly, the PDA could exert excellent photothermal conversion effect to simultaneously accelerate GSH consumption and improve the Fenton-like reaction for further expanding the intracellular oxidative stress, which innovatively achieves a synergistic photothermal-chemodynamic therapy for highly efficient anticancer treatment.