Borate ester-based multifunctional self-healing hydrogels for tissue adhesion and hemostasis

Uncontrolled bleeding post-surgery or trauma presents a significant medical challenge that often leads to complications such as hypotension, organ dysfunction, and mortality. Effective hemostatic agents are characterized by facilitating rapid bleeding cessation, adequate wet tissue adhesion, easy removal, and minimal hemolysis rate. Building on our previous work with tsPBA@PVA hydrogel, we developed a modified synthesis approach to yield Fe₃O₄@gel, designed to enhance hemostasis. This system is composed of Fe₃O₄, N1-(4-boronobenzyl)-N3-(4-boronophenyl)-N1,N1,N3,N3-tetramethylpropane-1,3-diaminium, tsPBA, and polyvinyl alcohol, PVA, which undergo a reaction to yield a borate ester. The hydrogel demonstrated excellent self-healing and adhesion properties by forming covalent bonds with diols on material surfaces. Moreover, the presence of polar functional groups within the hydrogel such as -OH, -CH, and -CO groups enabled strong hydrogen bonding with tissue surfaces. The hydrogel could also be easily removed from the wound site without causing rebleeding. <i>In vitro</i>, Fe₃O₄@gel exhibited a hemolysis rate of less than 5%. Both our <i>in vivo</i> and <i>in vitro</i> results demonstrated the formation of a blood clot enhanced by the presence of Fe₃O₄ in the hydrogel. These findings suggest the potential of Fe₃O₄@gel as a promising candidate for promoting hemostasis in wound healing.