A carboxymethyl cellulose/chitosan-based hydrogel harvests robust adhesive, on-demand detachment and self-healing performances for deep burn healing

The irregularities resulting from burns and the discomfort associated with changing dressings during treatment remain challenging to provide effective wound therapy. Hydrogels typically lack the capacity to adhere to tissue and are unable to remain at the wound site for an adequate duration, or fail to detach from tissue when required. In this study, a carboxymethyl cellulose/chitosan-based hydrogel with robust tissue adhesion, self-healing and on-demand detachment was designed via a Schiff-base reaction for deep burn healing. The network structure is self-repairing and does not require external stimulation. The injectable hydrogel fragments undergo self-healing, forming a piece of hydrogel that adapts to the shape of the wound and completely fills the scald wound. The Schiff-base reaction in the hydrogel is formed by the aldehyde group of dialdehyde-modified carboxymethyl cellulose (DCMC) and the amino group of dopamine modified carboxymethyl chitosan (CS-DA), which acts as a dynamic crosslink and endows the hydrogel with self-healing capability and on-demand detachment from tissues by using a benign amino acid solution. Additionally, the incorporation of dopamine has been demonstrated to augment the adhesive properties of the hydrogel. Cytotoxicity assays revealed that the hydrogels exhibit favourable biocompatibility. This research offers a promising approach for the management of burn injuries and represents a significant advancement in the development of cellulose/chitosan hydrogels for biomedical applications.