Importance of refrigeration time in the electrospinning of silk fibroin aqueous solutions

• Published in: Journal of materials science 2015-07, Vol.50 (14), p.4879-4887
• Main Authors: Aznar-Cervantes, Salvador D., Lozano-Pérez, A. Abel, García Montalbán, Mercedes, Víllora, Gloria, Vicente-Cervantes, Daniel, Cenis, Jose L.
• Format: Article
• Language: English
• Subjects: Additives; Aqueous solutions; Biomedical materials; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Crystallography and Scattering Methods; Density; Electrospinning; Elongation; Gelation; Materials Science; Mechanical properties; Modulus of elasticity; Original Paper; Polymer Sciences; Production costs; Refractivity; Refrigeration; Silk; Silk fibroin; Solid Mechanics; Ultimate tensile strength; Viscosity
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-015-9032-y

Refrigeration is a common method for preserving reconstituted silk fibroin (RSF) aqueous solutions during electrospinning experiments, but the effects of preservation time at 4 °C are still not well documented. In this work, we explore its effects on the viscosity, refractive index, and density values of RSF solutions at 19 wt%. Also, extensive characterization of the mechanical properties and fiber diameters of the resulting electrospun meshes are provided. Significant differences were found in elongation, Young´s modulus, and ultimate strength at different experimental times, and an increase in the viscosity values of the RSF solutions was detected for the first 12 days of storage. These solutions exhibited a continuous, slow gelation throughout the time in storage at 4 °C, and this phenomenon improved the performance of electrospinning after a certain period of refrigeration. The protocol used reduces the production cost of SF fiber-based scaffolds and avoids the use of harsh solvents and additives which could otherwise limit their use in potential biomedical applications.