Regenerated Silk Fibroin Fiber Wet Spinning And Cross-linking

Silk fibroin has good biocompatibility, collagen, chitosan and other natural polymermaterials are widely used in tissue engineering, drug delivery and other areas. Silkfibroin material for its ease of processing, can be made into fibers, films and porousscaffolds, gels and other forms of material. Addition to electrospinning, the regeneratedsilk fibroin fiber preparation method, you can also wet spinning technology has acertain mechanical properties of tissue engineering scaffolds. Regeneration of silkfibroin but poor mechanical properties of brittle fracture, after cross-linkingmodification process to improve the mechanical properties of recycled fiber is one ofthe researchers concerned about the direction.The cross-linking agent with protein side chains of amino, mercapto, hydroxyl, acovalent bond with, separated by close to two amino acid residues between the bypassand the formation of the polypeptide chain, chain or protein molecule cross Union, andnot cause a major change in protein conformation reagents.1-(3-dimethylaminopropyl)-3-ethyl carbodiimide hydrochloride (EDC)/N-hydroxythio-succinimide (NHS) system as a water-soluble crosslinking agent, and its own thecrosslinker intermediate products are water soluble, toxic residues will not becross-linked matrix, is good material modification of protein crosslinking agent.In this paper, the wet spinning technology, hexafluoro isopropanol (HFIP) andwater as a solvent, respectively, successfully regenerated silk fibroin fiber. Appearanceof the morphology of regenerated silk fibroin fiber by two methods, shows that thecharacterization of micro-structural performance, thermal changes and mechanicalproperties, the use of HFIP as solvent spun fiber of regenerated silk fibroin is about192um in diameter by1times led after stretch, the fiber diameter was significantlythinner, down to81um. The EDC/the NHS cross-linked modified, fiber swelling, thediameter increased to87um. For the silk II structure of the internal conformation ofregenerated silk fibroin fiber, fiber thermal decomposition peak increase, offset by281° C to288°C, but less than315°C of the thermal decomposition of natural silk fibroinpeak. The results show that the mechanical properties significantly increased breakingstrength and elongation at break of the fiber, respectively,1.41cN,/dtex. And11.38%,and show some flexibility. The mass fraction of between22%to32%of the regeneratedsilk fibroin aqueous solution spun regenerated silk fibroin fiber, modified via EDC/NHS crosslinking, a diameter of15.3±1.6um,16.8±2.3um and19.3±0.9um. Thesame time, the breaking strength and elongation at break of the fiber were1.16cN/dtexand3.25%, slightly lower than the breaking strength and elongation at break of theregenerated silk fibroin fiber obtained HFIP as the solvent. By the performance of theregenerated silk fibroin fiber to obtain the above two methods, we can see, the betterperformance of HFIP as solvent spun fibers of regenerated silk fibroin.