Polyvinyl alcohol/chitosan-Fe3+/gelatin/tri-network composite hydrogel wound dressing with effective hemostasis and self-healing properties

Multi-network hydrogels have attracted much attention for their excellent mechanical properties, antimicrobial properties and biocompatibility in wound healing. However, their application is limited by the lack of hemostatic properties and adhesion. Herein, we designed a hydrogel composed of polyvinyl alcohol (PVA) and chitosan (CS), and introduced a third network by doping gelatin. In order to improve the hemostatic properties of the hydrogels, the effect of Fe3+ doping amounts on the hemostatic properties of the hydrogels was investigated. The blood loss in the liver and tail hemorrhage models was 48 mg and 23 mg, respectively, which was only 23.5% and 20.3% of the hemostatic cotton ball (CB) control. The prepared triple reticulated hydrogel showed significant aggregation effect on blood platelets. Importantly, the hydrogel can quickly adhere to close the wound and has good hemostatic effect both in vitro and in vivo. The swelling rate exceeded 700% at 14 days indicating that the hydrogel has strong structural stability properties. The self-healing ability of hydrogels was investigated based on dynamic covalent and hydrogen bonding. Through the multi-crosslinking strategy, our work successfully prepared a polysaccharide bio-adhesive hydrogel dressing with self-healing, and good hemostatic properties, which has a promising application in emergency hemostasis and wound healing.