The Study Of Preparation And Properties Of Anticoagulant Silk Fibroin Film With DES As Solvent

Silk fibroin film is a kind of polymer biofilm,which has the advantages of non-toxic,non-sensitive,non-irritating and good biocompatibility.It is widely used in cosmetics,artificial tissues and organs,drug controlled release materials and so on.As a new type of green solvent,the deep eutectic solvent has good thermal stability,biodegradability,biocompatibility,non-toxic,low vapor pressure,non-flammabl,the atomic utilization rate is 100%.In this paper,the DES was used to dissolve silk fibroin under the condition of ultraviolet light,and silk fibroin film with excellent properties.Anticoagulant material is a very important biological material.It is often used to make biomedical materials that directly contact with human tissues and blood,such as artificial blood vessels and surgical lines.The material not only have good tissue compatibility,but also have good blood compatibility,so that the surface of the material should no coagulation.In this paper,lithium bromide / urea and lithium bromide / zinc chloride are used to dissolve silk fibroin under ultraviolet light.By changing the time of ultraviolet irradiation,the distance of the light source and the wavelength of ultraviolet light silk fibroin films with excellent mechanical propertie,and anticoagulation.Lithium bromide / urea deep eutectic solvent was used as the solvent to dissolve silk fibroin under ultraviolet light irradiation and to prepare silk fibroin film.The optimal ultraviolet light is obtained by comparing the mechanical properties and anticoagulantproperties of silk fibroin film.The optimal conditions is to use ultraviolet light with a wavelength of 254 nm,light source distance is 11 cm,and ultraviolet irradiation time is 6h.The average breaking strength of the film prepared under this condition was 25.88 MPa.Lithium bromide/zinc chloride deep eutectic solvent was used as the solvent to dissolve silk fibroin under the irradiation of ultraviolet light to prepare silk fibroin film.The optimal ultraviolet light is obtained by comparing the mechanical properties and anticoagulant properties of silk fibroin film.The optimal conditions is to use ultraviolet light with a wavelength of 254 nm,light source distance is 11 cm,and ultraviolet irradiation time is 6 h.The average breaking strength of the film prepared under this condition was 24.70 MPa.The films prepared under different conditions were characterized by Fourier transform infrared spectrometer,thermogravimetry,X-ray diffractometer,scanning electron microscope,atomic force microscope,and their wettability and swelling were tested.The results showed that the content of the ?-sheet structure of the film that dissolve under the ultraviolet light was increased,which is the reason that the mechanical properties of the film are enhanced.The anticoagulation performance of the films tested by the hemolysis rate,the dynamic coagulation time and the plasma recalcification time.The results showed that the film prepared under ultraviolet light had anticoagulant properties while the film prepared without ultraviolet light.The anticoagulant properties of the films prepared under different ultraviolet light conditions not significantly different.This paper combined with quantum chemical calculations reveals the mechanism of the formation,and further explained the interaction between the DESs and silk fibroin,and clarify its mechanism of dissolving silk fibroin.The structure optimization,the electrostatic potential analysis(ESP),and the reduced density gradient analysis(RDG)of DESs and silk fibroin were performed.The results indicate that weak interaction forces such as hydrogen bonds and van der Waals forces are the main driving forces for the formation of DESs and dissolve of silk fibroin.