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.