Journal of Materials Science

, Volume 50, Issue 14, pp 4879–4887 | Cite as

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

  • Salvador D. Aznar-Cervantes
  • A. Abel Lozano-Pérez
  • Mercedes García Montalbán
  • Gloria Víllora
  • Daniel Vicente-Cervantes
  • Jose L. Cenis
Original Paper


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.


Refrigeration Ultimate Strength Silk Fibroin Electrospun Fiber Fiber Size 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors acknowledge financial support from the European Commission (FEDER/ERDF), the Spanish MINECO Projects (MAT2011-24973 and CICYT CTQ2011-25613), and the SÉNECA foundation (1195/PI/09). Dr. A. Abel Lozano-Pérez’s research contract was partially supported (80 %) by the FEDER Operative Program of the Region of Murcia 2007–2013.

Supplementary material

10853_2015_9032_MOESM1_ESM.doc (1.2 mb)
Supplementary material 1 (DOC 1248 kb)


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Salvador D. Aznar-Cervantes
    • 1
  • A. Abel Lozano-Pérez
    • 1
  • Mercedes García Montalbán
    • 2
  • Gloria Víllora
    • 2
  • Daniel Vicente-Cervantes
    • 1
  • Jose L. Cenis
    • 1
  1. 1.Department of BiotechnologyInstituto Murciano de Investigación y Desarrollo Agrario y Alimentario (IMIDA)MurciaSpain
  2. 2.Department of Chemical Engineering Faculty of ChemistryUniversity of Murcia (UMU)MurciaSpain

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