Bioinspired pagoda-like microneedle patches with strong fixation and hemostasis capabilities

Efficient hemostasis is of great significance in clinical and medical fields. Herein, inspired by the hierarchical microstructure of feet or stings of insects, we present a dodecyl-modified chitosan (DCS)-coated pagoda-like multilayer microneedle patch for tissue fixation and rapid hemostasis. Such a microneedle patch is fabricated by a step-by-step mold replication, which is easy-to-operate, flexible, and highly adjustable. The multilayer structure enables the microneedle patch to strongly fix onto diverse tissues via physical interlocking and is not affected by large blood loss or other conditions; while the DCS coating can anchor onto the cell membrane, bring about blood cell coagulation, and thus actively promote hemostasis. It was demonstrated from in-vivo rabbit experiments that acute tissue injuries including liver bleeding, spleen bleeding, and kidney bleeding can be repaired immediately by employing these DCS-coated multilayer microneedle patches. These distinctive features indicate that the presented microneedle patches can find applications in hemostasis and many other biomedical fields.