Design and fabrication of pH-responsive skin scaffolds based on carrageenan and konjac glucomannan for accelerated wound healing

The aim of this study was to utilize pH-responsive hydrogel skin scaffolds to achieve the sustained release of bioactive compounds (BCs) to promote wound healing. ZIF-8@flavanone nanoparticles were successfully synthesized through microfluidic channels and integrated into a hydrogel scaffold consisting of carrageenan (KC) and konjac glucomannan (KGM) to create a pH-responsive composite hydrogel scaffold. The unique pore structure of ZIF-8 efficiently loaded the active material, and the coordination bonds were disrupted in a slightly acidic environment, allowing the release of flavonoids. The natural macromolecular polysaccharides KC and KGM have good biocompatibility, and as a moist but not wet hydrogel scaffold substrate, they more closely resemble the growth environment of cells and are more favorable for wound healing. The hydrogel scaffolds developed in this study had a tensile strength of 1.15 MPa, an elongation at break of 320 %, good biocompatibility, a relative cell viability of 99.6 %, relative antimicrobial rate of 96.3 % (E. coli) and 95.8 % (S. aureus), respectively, and a release rate of 43.3 % at a pH of 5.0, and a wound closure rate at 15 d of 90.5 %, contributing to the improvement of wound healing performance and providing new possibilities for customized antimicrobial wound dressings.