Study On The Bilateral Interactions Between Cells And Silk Fibroin Materials With Different Structures

Silk is an excellent natural protein fiber with many unique physical and chemical properties,especially good biocompatibility, no toxicity to the body, and no sensitization and stimulation.Besides, it not only has excellent physical and mechanical properties, but also performs goodbiodegradability, and the degradation products have no inflammatory reactions. In this paper, silkfibroin/amino acids blend films were prepared by mixing silk fibroin and amino acids at differentratios. The structure and physical and mechanical properties of the blend films were tested. Inaddition, biodegradability of different crystalline structure of silk fibroin membrane as well asbiocompatibility with L929cells was accessed.X-ray diffraction was used to investigate structure of the PRO/SF films, and the resultsshowed that the films were mainly composed of the crystalline structure of Silk Ⅰ. The dissolutionloss rate was greatly improved, and the results showed that when the content of proline exceeding20%the silk fibroin became insoluble. With the increase of the content of proline, the films’breaking elongation rate was increased significantly．This indicated that proline can significantlyimproved the flexibility of SF films.The effects of the different structure of the silk fibroin membrane to the degradation rate offilms were studied. The results showed that silk films with silkⅠcrystal structure preform thefastest degradation rate, while the films with Silk II crystalline structure showed slowestdegradation rate. Meanwhile, the degradation rate of the blend silk films which contained bothSilk I and Silk II crystalline structure was in the middle. What’s more, the proline blend filmsshowed fastest rate of degradation, and they were totally degraded just after3days.At last, this paper studied the cytocompatibility between L929cell and different structure ofsilk fibroin films (SF, PRO/SF, EG/SF, PG/SF, BDO/SF). The results showed that all types of silkfibroin films were able to support cell adhesion and proliferation withno difference, whichindicated that there was no relationship between cell proliferation and the crystal structure of thesilk fibroin membrane.