A self-healing hydrogel wound dressing based on oxidized Bletilla striata polysaccharide and cationic gelatin for skin trauma treatment

Skin trauma presents significant treatment challenges in clinical settings. Hydrogels made from naturally-derived polysaccharide have demonstrated great potential in wound healing. Here, a novel in-situ crosslinked self-healing hydrogel was prepared using oxidized Bletilla striata polysaccharide (BSP) and cationic gelatin via a Schiff-base reaction without the need for any chemical crosslinkers. Similar to the natural extracellular matrix, the BSP-gelatin hydrogel (BG-gel) exhibited typical viscoelastic characteristics. The rheological properties, mechanical behavior, porous structure, and degradation performance of BG-gel could be adjusted by changing the aldehyde group content of BSP. Importantly, the hydrogel showed superior hemostatic performance in mouse tail amputation and rat liver incision models. It significantly facilitated wound healing by promoting hair follicles regeneration, blood vessels repair, collagen deposition, and inducing skin tissue remodeling via increased CD31 expression in a full-thickness skin wound rat model. This multifunctional hydrogel holds potential as a wound dressing for skin trauma, offering both hemostasis and expedited healing.