PEGylated copper(II)-chelated polydopamine nanocomposites for photothermal-enhanced chemodynamic therapy against tumor cells

Photothermal-enhanced chemodynamic therapy is a novel and promising strategy for effective tumor treatment. Herein, a kind of polydopamine (PDA)-based nanoplatform is reported for photothermal-enhanced chemodynamic therapy against tumor cells. PDA nanoparticles (NPs) were prepared through the self-polymerization method, which were subsequently chelated with Cu2+ and linked with poly(ethylene glycol) (PEG) chains, finally obtaining PDA-Cu(II)-PEG NPs. The fabricated PDA-Cu(II)-PEG NPs were uniform in shape with a narrow polydispersity. They can firstly react with glutathione (GSH) to generate Cu+, inducing GSH depletion meanwhile. The formed Cu+ could catalyze H2O2 to produce hydroxyl radicals (OH) via a Fenton-like reaction. The formed PDA-Cu(II)-PEG NPs displayed good photothermal conversion efficiency and photothermal stability. They can be internalized by 4T1 cells effectively. Under near-infrared light irradiation, PDA-Cu(II)-PEG NPs can generate hyperthermia and OH for photothermal/chemodynamic therapy against tumor cells.