Structure and gelation mechanism of silk hydrogels

TitleStructure and gelation mechanism of silk hydrogels
Publication TypeJournal Article
Year of Publication2010
AuthorsNagarkar, S, Nicolai, T, Chassenieux, C, Lele, AK
JournalPhysical Chemistry Chemical Physics
Volume12
Issue15
Pagination3834-3844
Date PublishedFEB
ISSN1463-9076
Abstract

Silk fibroin was regenerated from cocoons produced by the silkworm Bombyx Mori. Light scattering showed that an aqueous solution of the regenerated silk fibroin (RSF) was made of individual proteins with a weight average molar mass of about 4 x 10(5) g mol(-1) and a hydrodynamic radius of about 10 nm. Gel formation of RSF in acidic solutions was investigated as a function of the pH (2-4), concentration (0.5-10 g L(-1)) and temperature (5-70 degrees C). The structure of the gels was studied using light scattering and confocal laser scanning microscopy. The structure was found to be self-similar from length scales of less than 15 nm up to length scales of about 1 mm, and characterized by a correlation length of a few microns. Gel formation was tracked using turbidity, rheology, light scattering and circular dichroism. Gelation involves the formation of self-similar aggregates with a growth rate that increases exponentially. The protein aggregation is correlated to, and perhaps caused by, the formation of beta-sheets, the fraction of which also increases exponentially with time.

DOI10.1039/b916319k
Type of Journal (Indian or Foreign)

Foreign

Impact Factor (IF)

3.453

Divison category: 
Polymer Science & Engineering