Injectable Living Probiotic Dressing Built by Droplet‐Based Microfluidics and Photo‐Cross‐Linking to Prevent Pathogenic Infection and Promote Wound Repair

Abstract The treatment of infected wounds faces great challenges due to the emergence of antibiotic resistance and the lack of persistence in drug release. Here, a living probiotic dressing is constructed by integrating droplet‐shearing and photo‐cross‐linking. Saccharomyces boulardii ( S. boulardii ), the only probiotic used clinically, is encapsulated and attached to a wound under light irradiation. A double‐layer hydrogel provides a protective barrier for cell growth and proliferation while preventing the escape of S. boulardii . The living probiotic dressing shows superior biosafety with fibroblast cells. Strikingly, in vitro and in vivo experiments indicate that the living probiotic dressing not only inhibits bacterial survival and colonization, but also alleviates inflammation and accelerates wound closure. More significantly, the living probiotic dressing promotes collagen deposition and neovascularization, which accelerates wound healing. This work can provide new ideas for clinical wound treatment and widen the application of probiotics in tissue engineering.