Tumor Microenvironment Activated Vanadium-Doped Carbon Dots for Fluorescence Imaging and Chemodynamic Therapy

The multifunctional platform response to the tumor microenvironment (TME) is critical for the high-precision diagnosis and treatment of cancer with low systemic toxicity. In this regard, vanadium-doped carbon dots (V-CDs) have been developed for TME-activated fluorescence imaging and chemodynamic therapy (CDT). Due to the Forster resonance energy transfer caused by the doped vanadium, the obtained V-CDs displayed quenched fluorescence. Once entering the tumor, the fluorescence imaging ability of the V-CDs are stimulated by the reaction between vanadium and overexpressed H2O2 in a weak acid TME. Meanwhile, the hydroxyl radicals generated by the catalytic reaction of V-CDs could induce oxidative damage in tumor cells for CDT, while showing less cytotoxicity and side effects in normal cells. Therefore, the well-designed V-CDs could be used for TME-activated fluorescence imaging and CDT while maintaining an "inactive" status in normal tissues to ensure low biological toxicity, satisfying the clinical requirements for accurate diagnosis and efficient treatment with low side effects for tumors. Our research provides an effective strategy for designing and preparing multifunctional nanotheranostic drugs responsive to TME for accurate tumor imaging and treatment.