Highly stretchable, self-adhesive, and biocompatible cellulose/chitosan based double network hydrogel for wound dressing.

Hydrogels are widely recognized for their excellent flexibility and biocompatibility, making them promising materials for skin regeneration and wound care. However, the practical application of traditional hydrogels is limited by their inadequate mechanical strength and poor adhesive properties, hindering their effectiveness in wound healing. In this study, we designed a cellulose-based composite hydrogel, which overcomes these limitations by combining cellulose dialdehyde (DAC), carboxymethyl chitosan (CMCS) and polymerizable acrylamide (AM). The hydrogel features a double network structure: a dynamic chemical bonding network via a Schiff base reaction and a covalent bonding network formed through free radical polymerization. The resulting hydrogel exhibited remarkable mechanical properties, including tensile strength (>400 kPa), stretchability (>1400 %), toughness (>2900 kJ m), and good self-adhesion to skin (2.7 kPa). Additionally, it demonstrated excellent biocompatibility and significantly accelerated wound healing in a mouse model of full-thickness skin defects. The synthesized hydrogel represents a promising advancement in the development of wound care materials. Its enhanced mechanical strength, self-adhesion, and biocompatibility make it a strong candidate for clinical applications in skin regeneration and wound therapy, addressing critical gaps in the current hydrogel-based wound care technologies.