Glycerol-plasticised silk membranes made using formic acid are ductile, transparent and degradation-resistant.
Benjamin J Allardyce, Rangam Rajkhowa, Rodney J Dilley, Sharon L Redmond, Marcus D Atlas, Xungai Wang
Mater Sci Eng C Mater Biol Appl | Published : 2017
Regenerated silk fibroin membranes tend to be brittle when dry. The use of plasticisers such as glycerol improve membrane ductility, but, when combined with aqueous processing, can lead to a higher degradation rate than solvent-annealed membranes. This study investigated the use of formic acid as the solvent with glycerol to make deformable yet degradation-resistant silk membranes. Here we show that membranes cast using formic acid had low light scattering, with a diffuse transmittance of less than 5% over the visible wavelengths, significantly lower than the 20% transmittance of aqueous derived silk/glycerol membranes. They had 64% β-sheet content and lost just 30% of the initial silk weigh..View full abstract