Figure 2.

Physical and chemical properties of supramolecular hydrogels. (A) ¹H NMR spectra of the glycol chitosan (blue line) and GC binder (red) in D₂O. (B) Images of LNSs with glycol chitosan and LNSs with GC binder. (C) Self-healing processes of supramolecular hydrogels: (1) two disk-shaped hydrogels stained with rhodamine B and methylene blue were cut into equal two pieces; (2) one piece of pink hydrogel and one piece of blue hydrogel were joined together to form two new hydrogels; (3) these two new hydrogels were immersed in PBS; (4) PBS was removed after 3 h; (5) these two new hydrogels were re-cut into equal two pieces; (6) two pieces of pink-blue hydrogels were joined together to form two new hydrogels; (7) these two new hydrogels were immersed in PBS again. (D) Self-healing of two hydrogels after attachment directly: (1) pink hydrogel and blue hydrogel were attached directly; (2) the new hydrogel was immersed into deionized water for 10 min; (3) the hydrogel was transferred from deionized water and maintained its shape. (E) Scheme diagram of the self-healing process. (F) Images of hydrogels injected from 23 G needle into water. (G) “ABC” gel could be formed after injection from 23 G needle. (H) Hydrogels with different shape could be obtained after injection from 23 G needle.