A Mussel-Inspired Antibacterial Hydrogel with High\nCell Affinity, Toughness, Self-Healing, and Recycling Properties for\nWound Healing

Abstract

Antibacterial\nhydrogels have been intensively studied due to their\nwide practical potential in wound healing. However, developing an\nantibacterial hydrogel that is able to integrate with exceptional\nmechanical properties, cell affinity, and adhesiveness will remain\na major challenge. Herein, a novel hydrogel with antibacterial and\nsuperior biocompatibility properties was developed using aluminum\nions (Al³⁺) and alginate–dopamine (Alg-DA) chains\nto cross-link with the copolymer chains of acrylamide and acrylic\nacid (PAM) via triple dynamic noncovalent interactions, including\ncoordination, electrostatic interaction, and hydrogen bonding. The\ncationized nanofibrillated cellulose (CATNFC), which was synthesized\nby the grafting of long-chain quaternary ammonium salts onto nanofibrillated\ncellulose (NFC), was utilized innovatively in the preparation of antibacterial\nhydrogels. Meanwhile, alginate-modified dopamine (Alg-DA) was prepared\nfrom dopamine (DA) and alginate. Within the hydrogel, the catechol\ngroups of Alg-DA provided a decent fibroblast cell adhesion to the\nhydrogel. Additionally, the multitype cross-linking structure within\nthe hydrogel rendered the outstanding mechanical properties, self-healing\nability, and recycling in pollution-free ways. The antibacterial test\nin vitro, cell affinity, and wound healing proved that the as-prepared\nhydrogel was a potential material with all-around performances in\nboth preventing bacterial infection and promoting tissue regeneration\nduring wound healing processes.