Polyphenol-driving assembly for constructing chitin-polyphenol-metal hydrogel as wound dressing

The metal-polyphenol networks have attracted appealing attention for diverse biomedical applications due to their remarkable characteristics. Though various of metal-polyphenolic materials have been prepared, the homogeneous metal-polyphenol based hydrogel fabrication remains a challenge (e.g., quick aggregation). Herein, a facile and low-cost polyphenol-mediating non-covalent driven assembly strategy was developed for fabricating homogeneous chitin-polyphenol-metal hydrogels. Polyphenols not only noncovalently crosslinked chitin chains, but simultaneously captured metal nanomaterials from metal substrates and immobilized in chitin-polyphenol networks. A range of metal (Fe, Cu, Ti, Zn) and polyphenol (tannic acid, gallic acid, quercetin, pyrogallic acid) could be incorporated into this hydrogel framework. As a demonstration, the chitin-tannic acid-Cu hydrogel showed excellent antibacterial properties and significantly enhanced infected wound repair via promoting the cell proliferation and angiogenesis, showing the potential in wound dressing. The low cost, versatility and flexibility assembly process can be used to fabricate diverse polymer-polyphenol-metal hydrogel, thereby enabling their use in various applications.