Study On Regenerated Silk Fibroin Porous Materials Prepared By Acid/Salt Solutin

Silk fibroin is a kind of natural macromolecular material with good biocompatibility, biodegradability and reprocesses ability, which is often used in the preparation of silk fibroin films with different structures and properties, hydrogels, and other regenerated silk fibroin materials. However,silk fibroin films prepared by traditional methods are fragile dense films with low water content; silk hydrogels have a high water content but their morphology structure are simple and their mechanical properties can’t meet the practical needs of biomaterials. Therefore, seeking new ways to prepare silk fibroin films with high water content and hydrogels with structure similar to extracellular matrix is an important way to improve the practicability of regenerated silk fibroin materials. Based on the preparation of gel-like films by acid/salt solution, this paper studied the influence of the concentration of silk fibroin and salt on the structures and properties of the gel-like films, and verified their biocompatibility and degradation by degradation experiment and cell culture experiment. Meanwhile, the products prepared by acid/salt solution were dissolved again to prepare freeze-dried scaffolds and gel-like films, and compare the differences between two-step dissolution products with the conventional ones.Firstly, this paper discussed the practicability of the preparation process of the gel-like films, and studied the influence of the concentration of silk fibroin and salt on the structures and properties, the results showed that both factors had influences on the surface morphology, water content, secondary structure and mechanical properties of the gel-like films. Degradation and cell culture experiments proved that the gel-like films had a good degradation properties and biocompatibility, which provided the basis for further study as practical biomedical materials. The freeze-dried solution prepared by the second dissolution had a unique micro fiber-like morphology, ultrasonic shear could change the morphology structure, and the cell culture experiments indicated the freeze-dried solution had a good biocompatibility. The gel-like films prepared by the solution had a fiber net structure, and the ultrasonic shear could radically reduce the gel time, the morphologies were also changed into layers. These experiments provided the basis for the gel time controllable and the preparation of hydrogels with structure similar to extracellular matrix.