Porous Materials with Water‐Triggered Instant Transformation to Robust Hydrogel Adhesives for Rapid Hemostasis of High‐Pressure Hemorrhages

Abstract Uncontrolled traumatic hemorrhage is a leading cause of preventable death. As two main forms of hemostatic materials, however, both sponges and hydrogel adhesives usually fail to control massive hemorrhage due to their respective shortcomings. Hemostatic sponge shows weak tissue adhesion, while the gelation process of hydrogel makes it difficult to seal high‐pressure bleeding wounds. There is an urgent need to develop next‐generation hemostats combining the advantages of sponges and hydrogel adhesives. Herein, a general methodology to prepare novel Fe 3+ ‐laden porous material (Fe 3+ @GCS) for rapid hemostasis of the high‐pressure and ‌severe hemorrhages is proposed, which is fabricated by loading ferric chloride with ethanol into the catechol‐modified carboxylated gelatin sponge (GCS). Notably, porous Fe 3+ @GCS can undergo water‐triggered rapid transformation‌ to robust‐adhesive hydrogels. The sealing strength of Fe 3+ @GCS on wet tissues reaches an astonishing ≈600 mm Hg. Rapid water uptake of Fe 3+ @GCS around wound not only concentrates blood components but also excludes interfacial water, facilitating blood clotting and wound sealing with the in situ formed sticky hydrogel. Fe 3+ @GCS can efficiently stop the high‐pressure hemorrhaging from traumatic injuries of arteries and hearts in rats and pigs, respectively, via a simple and short‐time pressing. Furthermore, the wound sealing by Fe 3+ @GCS promotes wound repair and healing.