| Autor: |
Strunk T; Institute for Biophysics, University of Bremen, Otto-Hahn-Allee 1, 28359 Bremen, Germany., Joshi A; Institute for Biophysics, University of Bremen, Otto-Hahn-Allee 1, 28359 Bremen, Germany., Moeinkhah M; Institute for Biophysics, University of Bremen, Otto-Hahn-Allee 1, 28359 Bremen, Germany., Renzelmann T; Institute for Biophysics, University of Bremen, Otto-Hahn-Allee 1, 28359 Bremen, Germany., Dierker L; Hochschule Bremen - City University of Applied Sciences, Neustadtswall 30, 28199 Bremen, Germany., Grotheer D; Chemical Process Engineering, Faculty of Production Engineering, University of Bremen, Leobener Str. 6, 28359 Bremen, Germany., Graupner N; HSB - City University of Applied Sciences, Department of Biomimetics, The Biological Materials Group, Neustadtswall 30, 28199 Bremen, Germany., Müssig J; HSB - City University of Applied Sciences, Department of Biomimetics, The Biological Materials Group, Neustadtswall 30, 28199 Bremen, Germany., Brüggemann D; Institute for Biophysics, University of Bremen, Otto-Hahn-Allee 1, 28359 Bremen, Germany.; MAPEX Center for Materials and Processes, University of Bremen, 28359 Bremen, Germany. |
| Abstrakt: |
Self-assembled fibrinogen nanofibers are promising candidates for skin tissue engineering due to their biocompatibility and ability to mimic the native blood clot architecture. Here, we studied the structure-property relationship and degradation of rehydrated fibrinogen nanofibers prepared by salt-induced self-assembly, focusing on the effect of scaffold layering, cross-linking time and freeze-drying. Optimal fiber stability was achieved with cross-linking by formaldehyde (FA) vapor, while treatment with liquid aldehydes, genipin, EDC, and transglutaminase failed to preserve the nanofibrous architecture upon rehydration. Scaffold layering did not significantly influence the mechanical properties but changed the scaffold architecture, with bulk fiber scaffolds being more compact than layered scaffolds. Freeze-drying maintained the mechanical properties and interconnected pore network with average pore diameters around 20 μm, which will enhance the storage stability of self-assembled fibrinogen scaffolds. Varying cross-linking times altered the scaffold mechanics without affecting the swelling behavior, indicating that scaffold hydration can be controlled independently of the mechanical characteristics. Cross-linking times of 240 min increased scaffold stiffness and decreased elongation, while 30 min resulted in mechanical properties similar to native skin. Cross-linking for 120 min was found to reduce scaffold degradation by various enzymes in comparison to 60 min. Overall, after 35 days of incubation, plasmin and a combination of urokinase and plasminogen exhibited the strongest degradative effect, with nanofibers being more susceptible to enzymatic degradation than planar fibrinogen due to their higher specific surface area. Based on these results, self-assembled fibrinogen fiber scaffolds show great potential for future applications in soft tissue engineering that require controlled structure-function relationships and degradation characteristics. |
