A Directional Porous Structure Hemostatic Sponge Based On Collagen Fibril And Its Properties

Blood plays a vital role in maintaining the body’s functions,excessive blood loss and related complications pose urgent clinical challenges.One of the preferred materials for hemostasis is collagen hemostatic sponge,or collagen sponge,which has excellent blood-absorbing and coagulation-promoting properties.However,the easy loss of biological activity of collagen during processing and the insufficient mechanical property of the finished product restrict the clinical practice of collagen sponges.Therefore,aiming to develop a collagen sponge with superior hemostatic performance,a preparation method of collagen sponge with controllable structure is established by using ice crystal template coupled freeze-drying technology from bovine collagen with stable bioactivity as raw material.The collagen sponge is further stabilized by cross-linking in situ with glutaraldehyde to improve its structural stability and mechanical properties.The main research contents are as follows:The collagen sponge is fabricated based on the characteristic quaternary(fibril)structure retained by the collagen raw materials,it has a directional porous structure with controllable porosity and low density,and high porosity.Many advantages such as the outstanding water absorption make the sponge superior to those currently used in clinical practice such as i Regene?,which have a disordered pore structure.Cross-linking further improved the mechanical strength(82.6 KPa)and water absorption performance(14607% ± 217%)of the collagen sponge by improving structural stability.Results showed that the collagen sponge have excellent in vitro /vivo hemostatic performance,significantly reducing wound hemostatic time(168.2 ± 22.2 s)and blood loss(1.5 ± 0.8 g)when applied to the rabbit auricular artery injury model.The hemostatic mechanism is explored,revealing that the collagen sponge not only enriches blood components and promotes the activation of coagulation pathway,but also activates platelets and promotes red blood cell aggregation.Additionally,the fibrinoid structure in the sponge cooperates with fibrin to form a network structure,which further accelerates the formation of thrombus.