Facile fabrication of a novel, photodetachable salecan-based hydrogel dressing with self-healing, injectable, and antibacterial properties based on metal coordination.

Achieving the controllable detachment of polysaccharide-based wound dressings is challenging. In this study, a novel, photodetachable salecan-based hydrogel dressing with injectable, self-healing, antibacterial, and wound healing properties was developed using a green and facile approach. A salecan hydrogel with a uniform porous structure and water content of 90.4 % was prepared by simply mixing salecan and an Fe-citric acid complexing solution in an acidic D-(+)-glucono-1,5-lactone environment. Metal coordinate interactions were formed between the released Fe ions and carboxyl groups on the salecan polysaccharide, inducing homogeneous gelation. Benefiting from this dynamic and reversible crosslinking, the salecan hydrogel exhibited self-healing and injectable behavior, facilitating the formation of the desired shapes in situ. The exposure of Fe-citric acid to UV light (365 nm) resulted in the reduction of Fe to Fe through photochemical reactions, enabling phototriggered detachment. Moreover, the hydrogel exhibited excellent biocompatibility and satisfactory antibacterial efficacy against Escherichia coli and Staphylococcus aureus of 72.5 % and 85.3 %, respectively. The adhesive strength of the salecan hydrogel to porcine skin was 1.06 ± 0.12 kPa. In vivo wound healing experiments further highlighted the advantages of the prepared hydrogel in alleviating the degree of wound inflammation and promoting tissue regeneration within 12 days.