Method and device for producing a thread from silk proteins
The present invention relates to a thread preparation process from silk proteins including an apparatus which is appropriate for performing the method. Furthermore, the invention is directed to the threads obtained therewith as well as the use thereof. The invention uses a diffusion unit leading to the production of high-quality silk threads with high yield.
1. A method for the preparation of a thread from recombinant silk proteins, comprising the following steps:
a) providing a solution of recombinant silk proteins;
b) transferring the solution into a diffusion unit containing a composition comprising potassium and phosphate ions;
c) passing the solution through the diffusion unit, wherein the solution comes into contact with the potassium and phosphate ions;
d) separating the solution into a silk protein-rich and poor phase;
e) obtaining the silk thread form the protein-rich phase.
2. The method according to claim 1 , wherein the spinning solution contains at least 1%-50% (w/v) silk proteins.
3. The method according to claim 1 , wherein the spinning solution contains 10-40% (w/v) silk proteins.
4. The method according to claim 1 , wherein the spinning solution contains 10-20% (w/v) silk proteins.
5. The method according to claim 1 , wherein the pH of the solution is 4.0-12.0.
6. The method according to claim 1 , wherein the pH of the solution is 6.5-8.5.
7. The method according to claim 1 , wherein the pH of the solution is 8.0.
8. The method according to claim 1 , wherein the solution comprises natural or synthetic silk proteins.
9. The method according to claim 8 , wherein the silk proteins are derived from the species Bombyx mori, Araneus diadematus , and/or Nephila clavipes .
10. The method according to claim 1 , wherein the solution comprises a polar solvent which is preferably selected from water, alcohols and mixtures thereof.
11. The method according to claim 1 , wherein the production of the silk thread includes contacting the protein-rich phase with a gas or a fluid.
12. The method according to claim 11 , wherein the gas is selected from O 2 , inert gases or mixtures thereof.
13. The method according to claim 1 , wherein the diffusion unit is formed of a gel material or ceramics.
14. The method according to claim 13 , wherein the gel material is selected from hydrogels, especially from polyacrylamide, cellulose derivatives, polyvinylmethylether (PVME), polystyrene-polybutadiene (PS-PB), stearylacrylate, polyethylene (PE), polystyrene (PS), polyvinylalcohol (PVA), polyacrylic acid, poly(N-vinylpyrrolidone) (PVP), polyethyleneterephthalate (PET), polyisopropyleneacrylamide, polyethersulfonic acid, silicone hydrogels.