Bacteriophage‐cocktail hydrogel dressing to prevent multiple bacterial infections and heal diabetic ulcers in mice

Bacteriophage (phage) has been reported to reduce the bacterial infection in delayed‐healing wounds and, as a result, aiding in the healing of said wounds. In this study we investigated whether the presence of phage itself could help repair delayed‐healing wounds in diabetic mice. Three strains of phage that target Salmonella enterica, Escherichia coli, and Pseudomonas aeruginosa were used. To prevent the phage liquid from running off the wound, the mixture of phage (phage‐cocktail) was encapsulated in a porous hydrogel dressing made with three‐dimensional printing. The phage‐cocktail dressing was tested for its phage preservation and release efficacy, bacterial reduction, cytotoxicity with 3T3 fibroblast, and performance in repairing a sterile full‐thickness skin wound in diabetic mice. The phage‐cocktail dressing released 1.7%–5.7% of the phages embedded in 24 h, and reduced between 37%–79% of the surface bacteria compared with the blank dressing (p