Starch-based adhesive hydrogel with gel-point viscoelastic behavior and its application in wound sealing and hemostasis

Hydrogels with tissue adhesiveness have demonstrated great promise for wearable electronics, artificial skin, soft robotics, and tissue repair. Nevertheless, adhesive hydrogels that are capable of sealing and hemostasis of wound with severe hemorrhage still lack. For this purpose, a series of ionically crosslinked starch hydrogels were developed here. The viscoelastic properties and tissue adhesiveness of the starch hydrogels were investigated. It is shown that the starch and cross linkers had significant influence on the viscoelastic properties of the starch hydrogels, which further resulted in varied tissue adhesiveness. Among the starch gels, there was one exhibiting a unique and stable “Gel Point” viscoelastic characteristic and it was named as gel-point adhesive hydrogel (GPAH). GPAH showed electrical conductivity, high tissue adhesiveness, high stretch-ability, self-healing capability, injectability, and degradability. The GPAH also exhibited high cytocompatibility, low hemolysis risk, and strong antibacterial effect. The wound sealing and hemostatic performance of GPAH was further evaluated by a rat femoral artery injury model. The blood loss after the sealing of GPAH (2.4 ± 1.3 g) was significantly decreased compared to the group using gauze for sealing (6.3 ± 1.5 g). Meanwhile, GPAH did not cause pathological changes of the soft tissues surrounding the wound. The above results indicate that GPAH, with high tissue adhesiveness, suitable viscoelastic property, strong antibacterial capacity, as well as electro-conductivity, bears great potential for the applications in smart wound management.