Figure 5.

Schematic illustration of the preparation of the hydrogel based on alginate (ALG), hydroxyapatite (HA), and carboxymethyl chitosan (CM)–CS. ALG was used for the preparation of HAH hybrids, then ALG was oxidized to form oxidized OHAH hybrid. In the next step, the Schiff base reaction between OHAH and (CM)–CS was launched. The self-healing property of the hydrogel was verified using two parts of the prepared hydrogels, one of the parts was mixed with methyl orange solution. Both parts were then spliced and characterized. Scheme describes: (A) the preparation of an injectable hydrogel using Schiff base reaction via chemical reactions as well as schematically, (B) the self-healing property of the hydrogels. HAH is hydroxyapatite alginate (HA/ALG) hybrids, OHAH is oxidized alginate hydroxyapatite hybrid. Adapted from [108], Elsevier, 2017.