Gas-jet propelled hemostats for targeted hemostasis in wounds with irregular shape and incompressibility

Since hemostats are likely to be flushed off a wound by a massive gushing of blood, achieving rapid and effective hemostasis in complex bleeding wounds with powder hemostats continues to be a significant therapeutic challenge. In order to counter the flushing effect of gushing blood, a gas-jet propelled powder hemostat ((COL/PS)₄@CaCO₃-T-TXA⁺) has been developed. (COL/PS)₄@CaCO₃-T-TXA⁺ dives into the deep bleeding sites of complex wounds for targeted hemostasis. In preparation, protamine sulfate and collagen are first electrostatically deposited on CaCO₃, which is then loaded with thrombin, and finally doped with protonated tranexamic acid (TXA-NH₃⁺) to produce the final therapeutic medicine (COL/PS)₄@CaCO₃-T-TXA⁺. When applied to bleeding tissues, CaCO₃ and TXA-NH₃⁺ from (COL/PS)₄@CaCO₃-T-TXA⁺ immediately react with each other in blood to release countless CO₂ macro-bubbles, which direct the hemostatic powder, (COL/PS)₄@CaCO₃-T-TXA⁺, precisely towards deep bleeding sites from complex wounds. Then the carried thrombin is released to accomplish targeted hemostasis. According to animal studies, (COL/PS)₄@CaCO₃-T-TXA⁺ has better effects in rabbit hepatic hemorrhage models; the hemorrhage quickly stops within 30 s, which is roughly 20% less than with the commercial product Celox^TM. The present study provides a new strategy for using powder hemostats to quickly and effectively stop bleeding in complex bleeding wounds.