Study On The Artificial Fibers And Tissue Engineering Scaffolds Based On The Recombinant Spider Silk Protein

The spider silk that belongs to fibrin is a biodegradable and non-pollution. Its high strength, tenacity and elasticity bring it comprehensive attention of researchers all over the world. Up to now, the spider silk has had great influence on textile industry, medical health, military field and so on. In the research, strategy to improve the yield of recombinant spider silk protein was discussed, and various factors related to silk fiber' s high performance in wet spinning were also analyzed. At home, we first reported the electrospinning of recombinant spider silk fibers, at the other hand, scaffolds prepared with the mixture of recombinant protein and other macromolecule materials were under the mechanical test. In the end, we examined the degradation behavior of recombinant protein and the biocompatibility about scaffolds made of the protein.Without lots of recombinant spider silk protein, silk fibers and scaffold materials can't be produced. Thus, above all, the propose was to obtain more protein through optimizing high-density fermentation and purification technics. We confirmed it is necessary to transform recombinant plasmid over again in period of time, so the problom on plasmid loss may be avoided. The best yield of the recombinant spider silk protein was up to 0.5g/L if providing 0.1%Gly/Ala and 0.4mM IPTG at OD₆₀₀ 35～45 by the fed-batch culture. By optimizing purification, we can get 3.5mg/g recombinant spider silk protein finally.In a wet spinning process, the spinning solution including 70% recombinant silk protein was extruded into ethanol, then the resulting fibers were stretched and dipped in water. The mixed silk fibers appeared white, uniform, with average diameter 50～70μm after lyophilized. The electrospinning method is used to produce fibers in nanometer, in our result, it can observed the fiber is about 300 nanometer. We could draw a conclusion that appropriate mixing ratio between silk protein and other materials availed to the mixed fiber's performance.Analyzing the degradation behaviour of recombinant silk protein, we found that degrading rate minished when protein mixed with other material. The scaffolds were dipped into water to remove acid molecule and NaCl, then high temperature made...