The Preparation Of Silk Fibroin Hemostatic Gauzeand Its Biocompatibility

In our daily life, we all need in a timely manner to prevent loss of blood whether it is because of accidental or surgical wound bleeding. With the improvement of living standards and the continuous improvement of hemostasis materials and methods. Past hemostasis stop bleeding relies mainly on mechanical ways, then slowly developed new hemostatic materials and drugs. Existing medical hemostatic materials are chitosan, collagen fibers, fibrin glue, oxidized cellulose, calcium alginate, gelatin sponges. However, these materials have shortcomings: biocompatiblity not good,expensive to synthesis, not fast enough to stop bleeding, easily lead to infection. The development of a biocompatible, low prices, excellent hemostatic properties material has great social benefits.Our country is a big country of sericulture with annual silk output of 100,000 tons.Currently, silk is mainly used in the textile industry. However textile alone can not take advantage of the huge resources of silk, a lot of silk material is wasted. We can get silk fibroin from cocoon by degumming, the quality of silk fibroin take up as high as 70%to 80% of that of cocoon. Silk fibroin is a natural polymer fibrin, compared with other natural protein, its unique molecular structure creates excellent mechanical properties,good absorption and retention properties. In addition, good bio-security, non-toxic,non-polluting, biodegradable, antibacterial and so on. Therefore, take the unique advantages of silk fibroin to develop bio-engineered material owms bright prospects.Therefore, this article intended to use degummed silk as the main raw material,improve water absorption of fibroin fibers through modification, adding procoagulant factors to improve its hemostatic properties.Then test biocompatibility and in vivo degradation ability hoping to obtain new hemostatic material of clinical value.First, residual lipids on cocoon and other antigen were removed by Soxhlet extraction using acetone、diethyl ether as extraction agent. Then pure silk fibers were prepared by degumming. Treat silk fibers with 10%, 20%, 40% CaCl2 solution and then-80 ℃ frozen for 2H, 4H, 6H, 12 H, 24 H, 48 H then dried or freeze-dried. The absorbency of modified silk fibroin fibers prepared increased from the initial 13.741 to a maximum of 25.713; Scanning Electron Microscope indicate absorption increase is due to the emergence of microvoids on uneven surface of silk and sub-fiber phenomenon; FTIR results confirmed that the secondary structure of modified silk fibroin fibers have no obvious change than that of natural silk fibroin, modified fibroinfibers still have all the excellent mechanical and biological properties of natural silk;BCI(Blood coagulation index) and rabbit ear vein blood model results showed that all silk hemostatic hemostatic material is superior to medical gauze, the amount of bleeding and bleeding time were less than medical gauze. 20% CaCl2 solution soaked then moved to-80℃ for 2H,freeze drying silk fibroin material process optimal hemostatic performance, 10% CaCl2 solution soaked then moved to-80℃ for 4H,dried silk fibroin material followed. Cytotoxicity(MTT) Experimental results show that all materials have no cell cytotoxicity but cell growth promoting function. In subcutaneous implantation test, no obvious wound swelling, redness or inflammation were found on subject mice, all living habits and physiological characteristics were normal which means all the materials have good biocompatibility. The results of tissue sections further show that, degradation of the materials occurred, and the degrees of degradation increaseed with time.To sum up, the hemostatic properties of silk fibroin hemostatic gauze are superior to medical gauze. And the material has good biocompatibility and a certain degree of degradatibility in vivo. It is expected to overcome the existing disadvantages of having biological toxicity and non-degradable in the body of hemostatic material existing. By optimizing the modification method, add better procoagulant factors, to further enhance the hemostatic properties of the materials prepared in this research is expected to create a new type of medical biodegradable hemostatic material.