Protamine-loaded quaternized chitosan hydrogel dressing featuring antibacterial and antioxidant properties for...

Postoperative periodontal wounds are in a complex physiologic environment, where accumulation of bacteria, stimulation of saliva, and retention of food residues are all prone to exacerbate wound deterioration. Although commercial periodontal dressings have been widely used in clinical practice, they still suffer from poor biocompatibility, weak adhesion, and insufficient antibacterial and anti-inflammatory properties. To overcome these limitations, we developed an innovatively designed, dynamically cross-linked multifunctional hydrogel (QCS-TA-PM) by integrating protamine (PM) into a network of quaternized chitosan (QCS) and tannic acid (TA). This design strategy endows the hydrogel with a combination of properties essential for advanced wound management, including high adhesive strength (42.67 ± 2.05 kPa), self-healing capability, injectability, potent broad-spectrum antibacterial activity (>85 % against both S. aureus and P. gingivalis) via bacterial membrane disruption, efficient ROS scavenging capacity (>80 %), and accelerated hemostasis by promoting erythrocyte and platelet aggregation. Furthermore, it significantly accelerates wound healing by suppressing inflammatory mediators, enhancing collagen fibers deposition, and promoting angiogenesis. Overall, a new multifunctional injectable hydrogel dressing was developed for postoperative periodontal tissue repair with significant potential for clinical application.