SiO₂-based inorganic nanofiber aerogel with rapid hemostasis and liver wound healing functions.

Abstract

Non-compressible hemostasis and promoting tissue healing are important in soft tissue trauma repair. Inorganic aerogels show superior performance in rapid hemostasis or promoting tissue healing, but simultaneously promoting non-compressive hemostasis and soft tissue healing still remains a challenge. Herein, SiO₂-based inorganic nanofiber aerogels (M²⁺@SiO₂, M=Ca, Mg, and Sr) were prepared by freeze-drying the mixture of bioactive silicates-deposited SiO₂ nanofibers and SiO₂ sol. These M²⁺@SiO₂ aerogels have a three-dimensional highly-interconnected porous structure, remarkable flexibility, high absorption, good hydrophilicity, negative zeta potential, and bioactive ions releasing capacity. M²⁺@SiO₂ aerogels not only exhibited satisfactory hemostasis activities in vitro, but also possessed high hemostatic efficacy in compressible rabbit femoral artery injury bleeding model and non-compressible rat liver puncture bleeding model compared to medical gauze and gelatin sponge. M²⁺@SiO₂ aerogel had low blood clotting index of Ca. 10 % and short partial thromboplastin time of ca. 82 s in vitro, and could greatly short bleeding time by >50 % and decrease blood loss by about 80 % compared to medical gauze and gelatin sponge in non-compressible hemostasis. Sr²⁺@SiO₂ aerogel showed optimal bioactivities on promoting cell proliferation, cell migration, and the expression of liver function and angiogenesis related genes and proteins in vitro. Importantly, Sr²⁺@SiO₂ aerogel possessed a noteworthy function to promote liver soft tissue healing in vivo by releasing bioactive ions and providing a highly-interconnected porous structure to support vascular development and tissue regeneration. Overall, Sr²⁺@SiO₂ aerogel has great potential for integrated rapid hemostasis and soft tissue healing, which is promising in soft tissue trauma therapy. STATEMENT OF SIGNIFICANCE: Non-compressible hemorrhage and soft tissue impairment are the main causes of mortality in emergency trauma. Inorganic aerogels with high porosity and outstanding flexibility can rapidly absorb blood to pro-coagulation and fill in irregular trauma without compression, but the low bioactivity limited the ability to promote soft tissue healing. Herein, SiO₂-based inorganic nanofiber aerogels (M²⁺@SiO₂, M=Ca, Mg, and Sr) were prepared by freeze-drying the mixture of bioactive silicates-deposited SiO₂ nanofibers and SiO₂ sol. M²⁺@SiO₂ aerogels possessed high bioactivity and exhibited superior hemostatic performance in compressible and non-compressible bleeding model. Furthermore, Sr²⁺@SiO₂ aerogel showed optimal bioactivities on cell responses and effectively promoted liver healing by releasing bioactive ions and providing highly-interconnected porous support structure for vascular development and tissue regeneration.