Diabetic Wound Healing Enabled by a Tri-Functional MAX Phase via Cu Doping

Due to complex pathological features and difficulty in healing wounds caused by diabetes, effective therapeutic agents and strategies remain elusive. Herein, we report on the development of Cu-doped single-phase Nb₂(Sn_0.7Cu_0.3)C MAX as a tri-functional therapeutic material for diabetic wound healing. The stable Nb-C lattice facilitates near-infrared plasmonic photothermal therapy, physically disrupting bacterial structures. Controllable Cu^{2 +} release mimics endogenous metal ion signaling, disrupting TCA metabolism to induce bacterial cuproptosis. Meanwhile, Cu^{2 +} also promotes regenerative macrophage phenotype and reduces excessive neutrophil activation. The Nb 4d-C 2p orbital hybridization simulates VEGF functionality to mediate angiogenesis. In vivo experiments demonstrate that Nb₂(Sn_0.7Cu_0.3)C promotes rapid infection clearance, initiating the wound healing process. This is followed by the restoration of immune homeostasis, ultimately leading to effective angiogenesis. Our Nb₂(Sn_0.7Cu_0.3)C overcomes the limitations of single-targeted therapeutic agents, capable of simultaneously addressing issues such as infection control, inflammation resolution, and tissue regeneration.