Universal Strategy to Enhance the Hemostatic, Antibacterial, and Wound Healing Performance of Polysaccharide Powders via a Water-Soluble Assembly Macromolecule.

Rapid and efficient hemostasis of massive bleeding wounds remains a major challenge in clinical practice. Self-gelling powders are now emerging as the new-generation hemostatic materials due to their capability to form hydrogels via a self-gelling process and thus integrate the merits of powders and hydrogels. However, they still face several unsettled issues, such as complex components, tedious synthesis, and poor compatibility with hemostatic powders on sale. Herein, we propose a universal strategy to enhance the hemostatic, antibacterial, and wound healing performance of polysaccharide powders via a water-soluble assembly macromolecule (tannic acid-grafted carboxymethyl chitosan, CCTA). When CCTA is blended with polysaccharide hemostatic powders and exposed to blood, the abundant ortho-phenolic hydroxyl groups of CCTA can build a dense hydrogen bonding network with swollen powders (i.e., microgels), erythrocytes, and platelets, leading to the in situ formation of microgel assembly with excellent mechanical strength, tissue adhesion, and thus sealing performance. In addition, CCTA also endows hemostatic powders with good antibacterial activities. The as-formed porous microgel assembly facilitates cell migration and ingrowth, leading to accelerated wound healing and tissue repair in vivo. Three types of polysaccharide powders and three bleeding models (rat femoral artery, rabbit liver, pig liver, and spleen) are used to validate our strategy.