An Injectable Multifunctional Extracellular Matrix-Based Hydrogel with Antibacterial and Pro-Regenerative Functions for Infected Wound Healing

Abstract

Infected wounds are characterized by a high bacterial burden and persistent inflammation, which frequently impair tissue regeneration. Conventional dressings or single-function hydrogels often fail to simultaneously meet the stage-specific requirements for infection control and tissue repair, and insufficient synergy between antibacterial and pro-regenerative functions remains a major challenge limiting healing efficiency. To address this issue, we developed an injectable bifunctional material system composed of sodium alginate microspheres (SAMS) and an extracellular matrix (ECM) hydrogel, designed to match the requirements of different healing stages in infected wounds.The composite employs a porcine decellularized dermis-derived extracellular matrix (dECM) hydrogel as the matrix and incorporates silver nanoparticles (AgNPs) to establish an antibacterial microenvironment conducive to early infection control. Meanwhile, SAMS loaded with basic fibroblast growth factor (bFGF) were embedded within the system to achieve sustained release of the growth factor through the microsphere structure. In vitro experiments demonstrated that the bifunctional composite exhibits effective antibacterial activity, good biocompatibility, and enhanced cell migration. A murine infected wound model further confirmed that the composite accelerates inflammation resolution and promotes angiogenesis and tissue regeneration, thereby significantly improving healing efficiency. Collectively, this composite demonstrates strong potential for application in infected wound repair.