Enhanced hemostatic performance of tranexamic acid-loaded chitosan/alginate composite microparticles

Novel microparticles based on chitosan and sodium alginate were prepared using emulsification and cross-linking technologies. The spherical microparticles had a porous surface and a diameter of 2 ~ 40 μm. In simulated body fluid, these microparticles quickly swelled but gradually degraded. The results of the MTT assay revealed that a slight inhibition of cell proliferation was observed on day 2 and then gradually decreased afterward. No cell morphology changes were observed. By loading tranexamic acid, the hemostatic performance of the microparticles was obviously improved. Using fast-acting styptic powder (Flashclot) as the control, the hemostatic efficiency was investigated in rabbits using a liver transection bleeding model. It was found that both Flashclot and the microparticles achieved hemostasis in 3.07 ± 0.84 min and 2.48 ± 0.88 min, respectively; however, the tranexamic acid-loaded microparticles stopped the bleeding in 1.90 ± 0.75 min (P < 0.05). Additionally, Flashclot resulted in heat injury to the experimental livers, while the microparticles did not. Thus, with their biodegradability, safety, and superior hemostatic efficiency, tranexamic acid-loaded microparticles might be a promising new powdered hemostatic agent with a wide range of potential applications.