Deep partial thickness
burn wounds present big challenges due to the long healing time, large size and irregular shape,
pain and
reinjury at
wound dressing changes, as well as
scarring. The clinically effective
therapy to alleviate
pain at
wound dressing changes, and the
scar left on the skin after the healing of
wound is still unavailable. To combat this, we develop a nanocomposite self-healing
hydrogel that can be injected into irregular and deep
burn wound beds and subsequently rapidly self-heal to reform into an integrated piece of
hydrogel that thoroughly fills the
wound area and protects the
wound site from external environment, finally being painlessly removed by on-demand dissolving using
amino acid solution at
wound dressing changes, which accelerates deep partial thickness
burn wound healing and prevents
scarring. The
hydrogel is made out of naturally occurring
polymers, namely, water-soluble
carboxymethyl chitosan (CMC) and rigid rod-like dialdehyde-modified
cellulose nanocrystal (DACNC). They are cross-linked by dynamic
Schiff-base linkages between
amines from CMC and
aldehydes from DACNC. The large aspect ratio and specific surface area of DACNC raise massive active junctions within the
hydrogel, which can be readily broken and reformed, allowing
hydrogel to rapidly self-heal. Moreover, DACNC serves as nanoreinforcing fillers to improve the
hydrogel strength, which also restricts the "soft" CMC chains' motion when soaked in aqueous system, endowing high fluid uptake capacity (350%) to
hydrogel while maintaining integrity. Cytotoxicity assay and three-dimensional cell culture demonstrate excellent biocompatibility of the
hydrogel and capacity as extracellular matrix to support cell growth. This work opens a novel pathway to fabricate on-demand dissolvable self-healing
hydrogels to speed deep partial thickness
burn wound healing and eliminate
pain at
wound dressing changes and prevent
scar formation.