Synergistic MS@Chl@Ag Composite System for Photothermal Antibacterial Therapy and Immune Microenvironment Modulation in Infected Wounds

Wound infection is a frequent and severe complication
that provokes
excessive inflammation, disrupts the wound microenvironment, suppresses
proliferation and angiogenesis, and delays wound repair. To overcome
these barriers, we developed an injectable MS@Chl@Ag (MSCA) therapeutic
platform integrating antibacterial, immunomodulatory, and regenerative
functions. Dextran microspheres were employed as carriers for silver
nanoparticles biosynthesized by Chlorella (Chl@Ag).
MSCA exploits silver nanoparticle-mediated photothermal therapy (PTT)
for rapid bacterial eradication, while Chlorella releases
bioactive factors that drive macrophage polarization toward an anti-inflammatory
phenotype, thereby reshaping the immune microenvironment. In addition,
the microspheres exhibit superior injectability and tissue adhesiveness,
allowing sustained Chl@Ag release and providing a favorable three-dimensional
scaffold that supports epithelial migration and neovascularization.
With its multifunctional and controllable design, MSCA demonstrates
a comprehensive strategy for infection-associated wound management,
effectively integrating bactericidal activity with immune regulation
and tissue regeneration.