Dual green hemostatic sponges constructed by collagen fibers disintegrated from Halocynthia roretzi by a shortcut method

Recently, biomacromolecules have received considerable attention in hemostatic materials. Collagen, an ideal candidate for hemostatic sponges due to its involvement in the clotting process, has been facing challenges in extraction from raw materials, which is time-consuming, expensive, and limited by cultural and religious restrictions associated with traditional livestock and poultry sources. To address these issues, this study explored a new shortcut method that using wild Halocynthia roretzi (HR), a marine fouling organism, as a raw material for developing HR collagen fiber sponge (HRCFs), which employed urea to disrupt hydrogen bonds between collagen fiber aggregates. This method simplifies traditional complex manufacturing processes while utilized marine waste, thus achieving dual green in terms of raw materials and manufacturing processes. FTIR results confirmed that the natural triple-helical structure of collagen was preserved. HRCFs exhibit a blood absorption ratio of 2000-3500 %, attributed to their microporous structure, as demonstrated by kinetic studies following a capillary model. Remarkably, the cytotoxicity and hemolysis ratio of HRCFs are negligible. Furthermore, during in vivo hemostasis tests using rabbit ear and kidney models, HRCFs significantly reduce blood loss and shorten hemostasis time compared to commercial gelatin sponge and gauze, benefiting from the capillary effect and collagen's coagulation activity. This study provides new insights into the design of collagen-based hemostatic biomaterials, especially in terms of both raw material and green manufacturing processes.