Dr. Michael Wöltje (Dresden, DE), Kristin Isenberg (Dresden, DE), Patrik Neubauer (Dresden, DE), Dr. Dilbar Aibibu (Dresden, DE), Prof. Dr. Chokri Cherif (Dresden, DE)
Abstract text (incl. figure legends and references)
Introduction
Silk fibroin combines properties such as high mechanical strength, biocompatibility, and biodegradability in vivo. The possibility of using fibroin in a wide variety of formats (films, scaffolds, hydrogels, and micro- or nanoparticles for drug delivery), has led to many interesting applications in medical research. In addition, extensive effort has been focused on producing man-made silk fibers by wet spinning. However, due to degradation of fibroin molecules during isolation from cocoons only high percentage solutions of regenerated silk (13-32 % w/v) show sufficient viscosity needed for fiber spinning.
Objectives
The main objective was to develop a novel wet spinning process to generate silk fibers and to process those fibers into 3D open porous scaffolds applying textile fiber-based additive manufacturing.
Materials & methods
Regenerated silk solution was isolated from Bombyx mori cocoons applying mild degumming and dissolution in ZnCl2. The resulting solution was freeze-dried and re-dissolved for wet spinning. Wet spun silk fibers were processed into staple fibers and then assembled into open porous 3D scaffolds applying fiber-based additive manufacturing.
Results
In contrast to all previously published spinning processes, a solvent/coagulation bath combination was developed, which enables continuously spinning of endless fibers from only 4 % (w/v) silk solution. Compared to other approaches the solid content to tensile strength ratio achieved was twice that of the highest process to date. Applying fiber-based additive manufacturing, those wet spun silk fibroin fibers were processed into 3D open porous scaffolds.
Conclusion
A novel process was developed enabling wet spinning of fibers from only 4 % (w/v) fibroin solution, which could be processed into 3D scaffolds with a fiber-based additive manufacturing technology.
Acknowledgements
This research was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)-437213841.