Injectable Hydrogel with Phase-Programmed Release of Centella asiatica Nanocomposites for Infection Control and Scarless Wound Healing

Infected wounds provoke persistent inflammation that hinders healing. Here, we developed a phase-adaptable, injectable hydrogel (PAC@TAP) that delivers sequential antibacterial, antioxidant, anti-inflammatory, and regenerative effects. Bioactive nanoparticles (AC@TAP) were prepared by loading Centella asiatica onto polydopamine, in situ polymerizing silver, and coating with tannic acid, then embedded in a dynamic QCS/OHA/PVA matrix. Reversible Schiff-base, ionic, and borate-ester cross-links (PVA/Ca²⁺/CPBA) endow injectability, self-healing, and strong tissue adhesion with PAC@TAP hydrogel. The composite hydrogel exhibits potent antibacterial activity, efficient ROS scavenging, and immunomodulation effects, thereby accelerating scar-minimizing healing of infected wounds. In vitro, PAC@TAP is cytocompatible and enhances cell migration. In vivo, near-infrared stimulation accelerates closure, dampens inflammation, and promotes angiogenesis. This integrated design uniquely couples antimicrobial defense with immune regulation and tissue regeneration, offering a promising strategy for advanced infected wound therapy.