Novel Self-Healing Hydrogel with Injectable, pH-Responsive, Strain-Sensitive, Promoting Wound-Healing, and Hemostatic Properties Based on Collagen and Chitosan.

Collagen (COL)-chitosan (CS) composite hydrogels are attracting increasing attention because of their great potential for application as biomaterials. However, conventional COL-CS hydrogels were easily disabled for lack of fully reversible linking in their networks. In this work, we developed a kind of self-healing hydrogel for wound dressing, composed of COL, CS, and dibenzaldehyde-modified PEG2000 via dynamic imine bonds, and the COL/CS hydrogels showed good thermal stability, injectability, and pH sensitivity, ideally promoting wound-healing performance and hemostatic ability. Furthermore, the hydrogel could monitor multiple human motions, especially the facial expression via strain sensitivity. This work offers a new perspective for the biomass-based hydrogels applied in medical field as wound dressing.