Silk fibroin/gelatin/calcium alginate composite materials: Preparation, pore characteristics, comprehensive hemostasis in vitro

Hemostasis is achieved through the comprehensive effect of multiple pathways. A composite porous material was designed consisting of silk fibroin (SF), gelatin (GA) and calcium alginate (CA), integrating the good biocompatibility of SF, swelling property of GA and hemostatic factor Ca2+ of CA. Water absorption, platelet adhesion, fibrinogen adsorption, blood coagulation activity, and cytotoxicity were investigated. Pore size in SF/GA porous materials increased with increasing content of GA in SF but decreased significantly in SF/CA porous materials after incorporating CA in SF. Based on the water binding capacity of materials and capillary effect of pores, the binary composites SF/GA1:1 and SF/CA3:1 displayed the best water absorption. Although GA and CA were more favorable for fibrinogen adsorption, SF/GA1:1 and SF/CA1:1 exhibited greater numbers of adhered platelets, shorter clotting times, and greater whole blood coagulation ability. Human skin fibroblasts spread well on the pure SF and GA and all the composites of SF/GA and SF/CA, and they showed high proliferative activity. Pure CA inhibited cell proliferation. For ternary composite materials, the comprehensive hemostatic ability of SF/GA/CA1:1:1 was greater than that of SF/GA/CA1:1:3.