Fabrication of amino-capped Pluronic F127 with aldehyde dextran chains: A strategy improving extensibility, compressibility and self-healing hydrogel for wound healing.

It is meaningful to develop polysaccharide hydrogel dressing with good mechanical and sustained-release properties, which can adapt to irregular wounds healing. To overcome defects of some polymers with amino groups, such as chitosan (more brittle), Poly(ethylenimine) (more toxic), and gelatin (less strength), a novel hydrogel (ODEX/APF) based on amino-capped Pluronic F127 (APF) as flexible crosslinking graft between aldehyde dextran (ODEX) chains was prepared in this study. The prepared ODEX/APF hydrogel exhibited rapid gelation under physiological conditions, endurable ductility and compressibility, excellent self-repairing ability based on Schiff base, and satisfied biocompatibility. Furthermore, amphiphilic APF can self-assemble into micelles that can be loaded with curcumin (Cur) and form drug-loaded composite hydrogels (ODEX/APF@Cur) with ODEX. The hydrogel has antimicrobial and anti-inflammatory properties and allows for long-term controlled release. In a full-thickness skin wound model, ODEX/APF@Cur hydrogel presented faster healing, less scaring, milder inflammation, better collagen distribution, downregulation of TNF-α, and upregulation of VEGF, promising applications in promoting wound healing.