Fe-coordinated carbon dots with single atom nanozyme catalytic activity for synergistic catalytic/chemo-therapy in breast cancer

Single atom nanozyme (SAzyme) based on carbon dots (CDs) has showed great potential in oncotherapy via ultrasmall size-reinforced atomically dispersed catalytic sites. However, its curative effect is still unsatisfactory due to complex tumor microenvironment and intrinsic resistance. Herein, a coordinated carbon dots (CCDs)-integrated ZIF-8 nanoassembly (Ru/CCDs-PTX@ZIF) was constructed by loading paclitaxel and coating with rutin for synergistic catalytic/chemotherapy. Benefiting from inherited metal-polyphenol coordination, the CCDs exhibited superior peroxidase-like (POD) activity and served as a SAzyme to produce large amounts of hydroxyl radical, resulting in radical-dependent cell cycle arrest. With the assistance of GLUT receptor-mediated endocytosis, the Ru/CCDs-PTX@ZIF triggered the tumor-targeted killing and migration inhibition to suppress tumor progression. This study highlights a promising avenue to broaden the design and applications of CDs-based SAzyme in tumor treatment.