Carbon quantum dots embedded graphitic carbon nitride for fluorescence imaging-guided combined tumor therapy

Metal-free carbon-based nanomaterials hold great potential for imaging-guided cancer therapy. In this work, we synthesized carbon quantum dots embedded graphitic carbon nitride nanofibers (GCN-CQD) via a facile one-pot solvothermal approach for fluorescence imaging and combined cancer therapy. Embedded CQDs impart excitation-dependent-tunable and upconverted fluorescence to the nanofibers, establishing them as robust optical contrast agents suitable for multicolor confocal imaging. Within the tumor microenvironment (TME), GCN-CQDs could catalyze hydrogen peroxide decomposition to generate hydroxyl radicals (˙OH) enabling chemodynamic therapy (CDT). Furthermore, GCN-CQD efficiently adsorbs near-infrared (NIR) light, converting it locally into heat for photothermal therapy (PTT) while simultaneously generating singlet oxygen (¹O₂) to drive photodynamic therapy (PDT), collectively inducing cell death. This work offers novel perspectives for developing multimodal combination therapy approaches utilizing metal-free carbon-based nanoplatforms.