Collagen-based injectable and self-healing hydrogel with multifunction for regenerative repairment of infected wounds

At present, the development trend of dressing materials is being multifunctional for convenient and long-term nursing care process of some complicated wounds. Here, basing on the theory of wound moist healing, an injectable and self-healing hydrogel comprising of collagen (COL), chitosan (CS) and oxidation modified Konjac glucomannan (OKGM), which acts as a macromolecular cross-linker to construct dynamic Schiff-base bonds was smartly designed. The strategy of introducing the silver nanoparticles (Ag NPs) into the COL–CS–OKGM hydrogel matrix achieved a markedly enhanced antibacterial activity derived from the synergistical effect between the Ag(+) and the mild photothermal efficacy of Ag NPs, which also improved the local capillary blood circulation of the wound area to further facilitate wound healing process. The excellent syringeability and self-healing behaviors endowed the COL–CS–OKGM–Ag hydrogel with self-adapting ability for the wounds with irregular and large area needing frequent applying and changing without secondary injuries. In vitro and in vivo evaluations verified that so-designed COL–CS–OKGM–Ag hydrogel also with hemostatic performance is a promising multifunctional dressing for the treatments of infected wound with not only good biocompatibility and convenient use, but also with desired regenerative healing prognoses benefited from hydrogel moist environment and physiotherapy.