Polyacrylic Acid-Based <i>Chlorella</i> Loading Hydrogel Featuring Antibacterial and Microenvironment Remodeling Properties for Expedited Wound Healing

Polyacrylic acid (PAA)-based hydrogels have been widely used in commercial wound dressings. However, they may trigger a series of adverse reactions within biological organisms due to PAA's nonbiodegradable nature and the difficulty of metabolism in physiological environments. To overcome this issue, a degradable PAA derivative (PLC) containing acrylic acid, α-lipoic acid (LA), and 2-(<i>N</i>-3-sulfopropyl-<i>N</i>,<i>N</i>-dimethylammonium)ethyl methacrylate was synthesized by reversible addition-fragmentation chain-transfer (RAFT) polymerization. Then, a multifunctional PLC-based hydrogel (CAPLCT@<i>Chlorella</i>) was developed through a facile mixture of PLC, tannic acid (TA), l-arginine-coupled chitosan (CA), and <i>Chlorella</i>. <i>Chlorella</i> in the hydrogel could constantly generate oxygen (O₂) through photosynthesis, relieving hypoxia. CA in the hydrogel endows CAPLCT@<i>Chlorella</i> the release of nitric oxide (NO), which could promote angiogenesis. The hydrogel not only exhibits excellent antibacterial and antibiofilm activities but can also relieve oxidative stress and modulate the inflammatory microenvironment. CAPLCT@<i>Chlorella</i> offers a promising therapeutic option for bacteria-infected wound healing.