A novel biocompatible polysaccharide-based self-healing hydrogel, CEC-l-OSA-l-ADH
hydrogel ("l" means "linked-by"), is developed by exploiting the dynamic reaction
of N-carboxyethyl chitosan (CEC) and adipic acid dihydrazide (ADH) with oxidized sodium
alginate (OSA). The self-healing ability, as demonstrated by rheological recovery,
macroscopic observation, and beam-shaped strain compression measurement, is attributed
to the coexistence of dynamic imine and acylhydrazone bonds in the hydrogel networks.
The CEC-l-OSA-l-ADH hydrogel shows excellent self-healing ability under physiological
conditions with a high healing efficiency (up to 95%) without need for any external
stimuli. In addition, the CEC-l-OSA-l-ADH hydrogel exhibits good cytocompatibility
and cell release as demonstrated by three-dimensional cell encapsulation. With these
superior properties, the developed hydrogel holds great potential for applications
in various biomedical fields, e.g., as cell or drug delivery carriers.
