Dual crosslinked injectable hydrogels with phytic acid coordination for robust underwater adhesion and rapid hemostasis.

Uncontrolled hemorrhage is a major cause of mortality in traumatic injuries, necessitating the development of efficient and biocompatible hemostatic materials suitable for clinical and emergency applications. Herein, we report a phytic acid (PA)-coordinated, dual-network injectable hydrogel composed of magnesium polyacrylate (PAMg), carboxymethyl chitosan (CMCS), and PA. The hydrogel is formed through both chemical and physical crosslinking, including covalent bonding, ionic interactions, and metal-ligand coordination, resulting in enhanced mechanical integrity, injectability, and biological performance. Structural and compositional characterization via FTIR and SEM revealed robust network formation and tunable porosity. The optimized hydrogel formulation exhibited high swelling capacity (up to 1076%) and maintained stable adhesion strength (>130 kPa) after prolonged PBS immersion. Hemostatic evaluation in rat liver injury models demonstrated a significant reduction in blood loss compared with control groups, while in vitro tests confirmed low hemolysis rates (<5%) and favorable cytocompatibility with L929 fibroblasts. This work presents a promising multifunctional hydrogel with mechanical strength, tissue adaptability, and biosafety for rapid hemostasis in moist internal environments.