Bioinspired nanofiber dressings with counter-transport of exudate and drug for treating heavily exuding wounds

Heavily exuding wounds are difficult to heal due to the accumulation of a large amount of exudates and the difficulty in efficient delivery of drugs by conventional wound dressings. Herein, inspired by the microstructure and function of octopus sucker (OS) and tree trunk (TT), we propose a bioinspired strategy to fabricate novel bioinspired OS&TT bilayered wound dressing, assembled by a lower OS-like nanofiber membrane with concave convex arrays and an upper TT-like nanofiber sponge with vertically aligned pores. The integration of bioinspired concave arrays and vertically aligned pores endows the bioinspired OS&TT dressing with dual vertical suction property, enabling effective drainage of significant amount of accumulated liquid. Moreover, the bioinspired convex arrays facilitate distinct drug reverse delivery, achieving a drug delivery efficiency exceeding 88.27 %. In vivo heavily exuding wound treatment results indicate that, the bioinspired OS&TT dressing can alleviate tissue edema, decrease the contents of proinflammatory cytokines, and accelerate wound healing due to the unique dual vertical suction of exudates. When treating the bacteria-infected wound, benefiting from the reverse delivery of antimicrobial ε-polylysine to efficiently kill bacteria, the bioinspired OS&TT dressing shows a better wound healing effect than the dressing with inefficient drug delivery capacity.