Surface roughness of silk fibroin/alginate microspheres for rapid hemostasis in vitro and in vivo

Timely hemostatic treatment is important to reduce blood loss and improve survival. To increase the speed of blood coagulation, hemostatic microspheres with varying degrees of surface roughness were prepared by emulsion cross-linking of sodium alginate (SA) and silk fibroin (SF). Surface morphology and hemostatic properties were analyzed with scanning electron microscope (SEM), infrared spectroscopy, and blood coagulation experiments. The results showed that microsphere have the roughest surface when the volume ratio of SA to SF is 2:1 (SF/SA2). These microspheres have the largest number of aggregated red blood cells, the fastest coagulation rates, and the strongest coagulation strength. Not only microspheres are they non-cytotoxic but they also promote cell growth. In vitro and in vivo coagulation experiments demonstrated that SF/SA2 microspheres can reduce bleeding time and volume and improve hemostatic efficiency, which suggests that SF/SA2 microspheres are potential hemostatic agents equipped with excellentbiosecurity.