Rapid Self‐Gelling Powder Forms Dual‐Crosslinked Hydrogel for Robust Tissue Adhesion and Non‐Compressible Hemorrhage Control

Uncontrolled hemorrhage remains a critical global health challenge, particularly in cases of non‐compressible bleeding. This study presents a sequentially dual‐crosslinked hemostatic powder that combines rapid hydration‐activated electrostatic gelation with photo‐triggered covalent reinforcement. The powder consists of negatively charged double bond‐functionalized polyacrylic acid (PAA‐db) and positively charged polyethyleneimine (PEI), enabling ultrafast fluid absorption and self‐gelation upon contact with biological fluids. Subsequent light irradiation induces covalent crosslinking, enhancing the mechanical property. The powder‐derived dual‐crosslinked PAA‐db/PEI (dPAA‐db/PEI) hydrogel enables rapid and robust tissue adhesion. In the severe non‐compressible hemorrhage models, the hemostatic powder outperforms clinical hemostatic agents (fibrin glue, CELOX powder), in terms of minimizing hemostatic time and blood loss. This hemostatic powder offers a promising solution for managing severe non‐compressible hemorrhage, demonstrating rapid sealing, robust mechanical performance, and excellent biocompatibility.