Fabrication of Three-Dimensional Porous keratin/PEO biological scaffolds

摘要

In order to prepare the keratin biological scaffold, keratin was firstly extracted from human hair by immersing in 200 mL of aqueous solution containing 7 mol/L urea, 2 wt% Sodium dodecyl sulfate (SDS), and 5 wt% sodium disulfite (Na_2S_2O_6). The mixture was then heated to 95°C, shaking for 4 h, and filtered through a stainless-steel mesh, dialyzed against 3 L of distilled water, with cellulose tubing having a molecular weight cutoff of 10000～14000 Da for 36 h and filtered again. To examine the property of keratin scaffold, the vacuum freeze-drying process of pure keratin was investigated to find the optimum process. In order to further improve the property of keratin scaffold, different contents of Poly Ethylene Oxide (PEO) were added into the keratin solution. The result showed that the optimum freezing process was that Freezing at room temperature for 4 h, and then put the sample into the refrigerator from ambient temperature to -20°C for 4 h. Then the sample was put into the cold trap for 24 h at -56°C. During the last 4 hours, the vacuum pump was opened and the frozen temperature was raised gradually. The keratin scaffold with good mechanical properties and uniform porosity was fabricated when the concentration of keratin solution was 10 wt%. Additionally, PEO plays an important role in improving the flexibility of keratin/PEO scaffold.