Tough Double Network Hydrogel and Its Biomedical Applications

Soft and wet hydrogels have many similarities to biological tissues, though their mechanical fragility had been one of the biggest obstacles in biomedical applications. Studies and developments in double network (DN) hydrogels have elucidated how to create tough gels universally based on sacrificial bond principles and opened a path for biomedical application of hydrogels in regenerative medicine and artificial soft connective tissues, such as cartilage, tendon, and ligament, which endure high tension and compression. This review explores a universal toughening mechanism for and biomedical studies of DN hydrogels. Moreover, because the term sacrificial bonds has been mentioned often in studies of bone tissues, consisting of biomacro-molecules and biominerals, recent studies of gel-biomineral composites to understand early-stage osteogenesis and to simulate bony sacrificial bonds are also summarized.

Automated summary

Double network hydrogels have been developed as tough materials for biomedical applications, such as regenerative medicine and artificial soft tissue engineering. Research has focused on enhancing the toughness of hydrogels based on sacrificial bond principles, as well as exploring gel-biomineral composites for early-stage osteogenesis and modeling bony sacrificial bonds.