Immediately activating hemostatic cellulose sealants for uncontrolled hemorrhage

The control of bleeding is one of the most important processes in surgical treatments and wound healing, and the development of effective hemostatic agents is urgently required. An ideal hemostatic agent should be immedi-ately activated when exposed to bleeding to reduce blood loss as soon as possible and should be user-friendly for urgent situations. To meet these demands, we functionalized carboxymethyl cellulose (CMC) with two different phenolic moieties, catechol (CA) and pyrogallol (PG), and then formulated each CMC derivative into adhesive hydrogels with high hemostatic ability. These hemostatic platforms exhibited sturdy modulus (CMC-CA: 0.55 +/- 0.08 kPa, CMC-PG: 1.37 +/- 0.24 kPa), wet-tissue adhesiveness (CMC-CA: 2.19 +/- 0.53 kPa, CMC-PG: 3.13 +/- 0.25 kPa), and rapid crosslinking within seconds for wound closure. We transformed the CMC hydrogels into a patch design, resulting in 16-19-fold increase in elastic modulus and 3-4-fold increase in adhesiveness, which can completely seal the wound for more efficient hemostatic action. The adhesive CMC patches exhibited superior hemostatic capability to fibrin glue as a wound sealant by rapidly stopping bleeding in mouse liver hemorrhage. This study demonstrated that bio-inspired polyphenolic CMC hydrogels produce a highly effective, instantly working hemostatic agent.