Dual-Responsive Cu(I) and Cu(II) Co-Doped Carbon Dots for Synergistic Chemodynamic-Photothermal Antitumor Therapy

Multifunctionalnanoplatforms have shown great promise in cancertherapy. However, their efficacy is limited by the low specificityand the tumor microenvironment (TME). Many functional organic acids,such as folic acid and gallic acid, have shown important potentialin the research of antitumor drugs. Herein, we report the preparationof the biocompatible theranostic carbon dots (FG@Cu-CDs) with folicacid, gallic acid, and CuSO4 as the precursors to realizethe TME and near-infrared photothermal dual response. Cu(II) of FG@Cu-CDsis sensitive to glutathione (GSH) in the TME, which reduced the consumptionof & BULL;OH by glutathione (GSH). Cu(I) in FG@Cu-CDs could treat cancerby chemodynamic therapy (CDT) through a Fenton-like reaction. Moreover,FG@Cu-CDs could ablate tumors through photothermal therapy (PTT),which also has a positive effect on promoting CDT and depleting GSH.Based on the facts that CDT/PTT could enhance host immunogenicity,we used an immune checkpoint blocker, anti-PD-L1 antibody (& alpha;PD-L1),to boost tumor immunotherapy. This work opens up the possibility formultifunctional organic-acid-derived carbon dots combined with immunecheckpoint blockers in cancer immunotherapy.