Strong and Rapidly Self‐Healing Hydrogels: Potential Hemostatic Materials

Abstract

Benzaldehyde‐terminated telechelic four‐armed polyethylene glycol (PEG‐BA) is synthesized and cross‐linked with carboxymethyl chitosan (CMC) to form dynamic hydrogels with strong mechanical performance. The gelation temperature and time, mechanical performance, and self‐healing behaviors are systematically investigated. The hydrogels have good storage modulus up to 3162.06 ± 21.06 Pa, comparable to conventional bulk hydrogels. The separated alternate hydrogel lines connect together to become an integrated hydrogel film after 5 min at room temperature without any external intervention. This is due to the dynamic equilibrium between the Schiff base linkages and the aldehyde groups of PEG‐BA and amine groups on CMC backbone. The hydrogel shows excellent cytocompatibility and the cell viability is as high as 90.7 ± 6.8% after 2 d 3D encapsulation in the hydrogel. In vivo tests indicate that the hydrogels can effectively stop bleeding when the hydrogel is directly injected into a rabbit liver incision. The total blood loss is reduced from 0.65 ± 0.10 g to 0.29 ± 0.11 g, and the hemostasis time is decreased from 167 ± 21 s to 120 ± 10 s, when compared to a gauze treatment with physical compression. These self‐healing hydrogels have potential to be used as a novel hemostatic material.