Fabrication of dual physically cross-linked agarose-based double network composite hydrogels with antibacterial and...

An agarose-based double network composite hydrogel with good mechanical, antibacterial, and hemostatic properties was synthesized to accelerate the healing of infected wounds. The double network composite hydrogel was fabricated by hydrogen bonding between poly(ACG-co-NBAA) chains generated by free radical polymerization and helical conformation formed by the agarose-graft-gelatin chains in the presence of Zn-MOF. The synthesized hydrogels exhibited a three-dimensional network structure and excellent pH sensitivity. The disintegration of hydrogen bonds in the hydrogel network caused the increase of swelling ratio of the hydrogels as the pH rose. The mechanical and antibacterial properties of agarose-based composite hydrogels can be well adjusted by changing their composition. The special structure of the hydrogels and Zn-MOF embedding endowed them with good antibacterial properties against S. aureus and E. coli. The results of the hemostasis experiment found that the agarose-based composite hydrogels had a lower BCI value, and the mice treated with the hydrogel sample had lower blood loss and shorter hemostasis time, indicating that the synthesized hydrogels had good hemostatic performance. In addition, a full-layer skin wound infection model demonstrated that the agarose-based composite hydrogels can accelerate the healing of infected wounds, and the wound healing rate of mice treated with the hydrogel sample can reach 97.6 ± 0.8 % at 14 days. Therefore, a biocompatible agarose-based double network composite hydrogel with good mechanical, antibacterial, and hemostatic properties, is expected to be used as a medical dressing to promote the healing of infected wounds.