We thank the NIH (R01 DE13405–04, R01EB003210–02), the NSF (DMR-0090384), and the DoD (Air Force) for support of this program. Cocoons of B. mori silkworm silk were kindly supplied by M. Tsukada, Institute of Sericulture, Tsukuba, Japan.
Water-Stable Silk Films with Reduced β-Sheet Content†
Article first published online: 1 JUL 2005
Copyright © 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Advanced Functional Materials
Volume 15, Issue 8, pages 1241–1247, August, 2005
How to Cite
Jin, H.-J., Park, J., Karageorgiou, V., Kim, U.-J., Valluzzi, R., Cebe, P. and Kaplan, D. L. (2005), Water-Stable Silk Films with Reduced β-Sheet Content. Adv. Funct. Mater., 15: 1241–1247. doi: 10.1002/adfm.200400405
- Issue published online: 25 JUL 2005
- Article first published online: 1 JUL 2005
- Manuscript Accepted: 18 APR 2005
- Manuscript Received: 7 SEP 2004
- Biomedical applications;
Silk fibers have outstanding mechanical properties. These fibers are insoluble in organic solvents and water, are biocompatible, and exhibit slow biodegradation in vitro and in vivo due to the hydrophobic nature of the protein and the presence of a high content of β-sheet structure. Regenerated silk fibroin can be processed into a variety of materials normally stabilized by the induction of β-sheet formation through the use of solvents or by physical stretching. To extend the biomaterial utility of silk proteins, options to form water-stable silk-based materials with reduced β-sheet formation would be desirable. To address this need for more rapidly degradable silk biomaterials, we report the preparation of water-stable films from regenerated silk fibroin solutions, with reduced β-sheet content. The keys to this process are the preparation of concentrated (8 % by weight) aqueous solutions of fibroin and a subsequent water-based annealing procedure. These new materials degrade more rapidly due to the reduced β-sheet content, as determined in vitro via enzymatic hydrolysis, yet support human adult stem-cell expansion in vitro in a similar or improved fashion to the crystallized proteins in film form. These new silk-based materials extend the range of biomaterial properties that can be generated from this unique family of proteins.