Injectable, self-healable and antibacterial multi-responsive tunicate cellulose nanocrystals strengthened supramolecular hydrogels for wound dressings

Wound dressing with an improved structural and functional recapitulation of damaged organs, efficient selfhealing and antibacterial properties that can well integrate with tissue are urgently needed in wound management. Supramolecular hydrogels confer control over structural properties in a reversible, dynamic and biomimetic fashion. Herein, a kind of injectable, self-healing and antibacterial supramolecular hydrogel with multiresponses were fabricated by mixing phenylazo-terminated Pluronic F127, quaternized chitosan-graft-cyclodextrin and polydopamine coated tunicate cellulose nanocrystals under physiological conditions. By exploiting the photoisomerization of azobenzene under different wavelengths, a supramolecular hydrogel featuring a changing crosslink density of network was obtained. The corporation of polydopamine coated tunicate cellulose nanocrystals strengthens the hydrogel network with Schiff base bonds and hydrogen bonds, which avoids complete gel-sol transition. The inherent antibacterial property, drug release behavior, self-healing ability, hemostatic performance and biocompatibility were investigated to confirm superiority in wound healing. Moreover, the curcumin loaded hydrogel (Cur-hydrogel) showed multi-responsive release profiles (light, pH, and temperature). A full-thickness skin defect model was built to confirm that Cur-hydrogels significantly accelerated wound healing rate with better granulation tissue thickness and collagen disposition. Overall, the novel photoresponsive hydrogel with coherent antibacterial property has great potential in the healthcare of wound healing.

Automated summary

An injectable, self-healing and antibacterial supramolecular hydrogel with multiresponses was developed for wound dressing. The hydrogel was fabricated by mixing Pluronic F127, quaternized chitosan-graft-cyclodextrin, and polydopamine coated tunicate cellulose nanocrystals. The hydrogel exhibited changing crosslink density of network through the photoisomerization of azobenzene, and its antimicrobial property was enhanced by the incorporation of cellulose nanocrystals. The hydrogel showed superior wound healing performance, as confirmed by in vitro and in vivo experiments.