Mussel-inspired hydrogels as tissue adhesives for hemostasis with fast-forming and self-healing properties

The application of traditional commercial and clinical tissue adhesive materials such as fibrin and albumin-glutaraldehyde are limited because these materials do not possess all the requirements for biomaterials, including high mechanical strength, strong wet adhesion, and good biocompatibility. We have developed a novel bio-inspired hydrogel (HA-catechol/4-arm-PEG-SH) based on a catechol-modified polymer with 4-arm-PEG-SH as a cross-linker that exhibits excellent wet adhesion in aqueous environments. Because the Michael addition reaction between 4-arm-PEG-SH, which contains a large amount of thiol groups, and catechol groups is highly efficient, the HA-CA/4-arm-PEG-SH hydrogel exhibits excellent wet adhesion and outstanding mechanical strength. Thus, the hydrogel shows promise as a hemostatic material. At the same time, the self-healing property of the hydrogel allows it to withstand high strain and repeated deformation. The hydrogel automatically recovers its mechanical properties and structure after deformation, making it effective for hemostasis. Moreover, the hydrogel can quickly gel within 30 s and shows good cell compatibility with slight promotion of cell proliferation. The HA-CA/4-arm-PEG-SH hydrogel is a promising bioadhesive for biomedical applications.