Photothermal-responsive fiber dressing with enhanced antibacterial activity and cell manipulation towards promoting...

For chronic persistent skin injuries, functional wound dressings with improved antibacterial action and cell control are extremely appealing. In this study, we design and fabricate a composite fiber dressing with near-infrared (NIR) laser-induced hyperthermia and transformable topographies that can protect the wound from bacterial infection while also encouraging cell recruitment and tissue regeneration. Polycaprolactone/gelatin (PCL/Gel) with melting point close to photothermal temperature were electrospun as the supporting matrix. The zeolitic imidazolate framework-8 (ZIF-8)-derived nanocarbon was synthesized as NIR laser-triggered nanoagent and then electrospun within oriented PCL/Gel fibers to enable the inorganic/polymer composite fiber dressing with photo-to-thermal conversion effect and drug loading capability. The composite fiber dressing exhibits excellent photothermal performance and stage-specific transformable topographies (photothermal-triggered melting behavior of oriented PCL/Gel fibers) after multiple laser irradiations, which can generate local massive heat and abundant drug release for synergistic sterilization, as well as direct cell migration and adhesion/spreading to promote tissue regeneration. Furthermore, in vivo testing demonstrates that the photothermal-responsive fiber dressing accelerates wound closure process by synergistically improving antibacterial and cell manipulation. Overall, this composite fiber dressing offers a promising integrated wound healing strategy.