Carboxymethyl chitosan/PVA-based dynamic cross-linked dual network hydrogel loaded with berberine with self-healing, self-adaptive, sustainable release and antibacterial ability for dressing

Developing novel dressings with superior antibacterial properties to resist bacterial infections during wound healing remains a significant challenge. Hydrogels have emerged as prominent materials due to their excellent biocompatibility and adjustable functionality, and are widely applied in the field of wound therapy. However, the majority of hydrogels exhibit suboptimal mechanical properties, which hinder their practical application. In order to integrate dynamic function design and remarkable antibacterial activity, a dual-network (DN) hydrogel with multiple dynamic bonds was designed and constructed. Specifically, carboxymethyl chitosan (CMCS) and polyvinyl alcohol (PVA) were used as hydrogel matrix. Oxidized sodium alginate (OSA) and borax were utilized as crosslinking agents, resulting in the formation of Schiff base bonds and borate ester bonds with CMCS and PVA, respectively. Concurrently, berberine (BBR) was incorporated into the system to impart sustainable release properties and elevated antibacterial efficacy. The maximum antibacterial rates of the hydrogel against Escherichia coli (E. coli) and Staphylococcus aureus ( S. aureus ) reached 97.1 % and 99.9 %, respectively, exhibiting remarkable synergistic antibacterial activity. Furthermore, the dynamic crosslinked DN hydrogel endowed it with exceptional mechanical properties, malleability, adhesion, self-healing, and self-adaptive ability, rendering it more efficacious in actual wound sites. Moreover, the hydrogel also exhibited favorable blood and cell biocompatibility, characterized by a hemolysis rate of less than 1 % and cell viability exceeding 90 %. Overall, the multifunctional hydrogel demonstrates considerable potential in addressing the challenges associated with infectious wound healing, thus indicating its candidacy as a promising wound dressing.