The Viscosity of Urea Solutions of Keratin

Abstract

The viscosity-concentration relationships for wool dispersed in concentrated urea solutions are comparable with those reported for globular proteins in urea. The axial ratios calculated from the viscosity increments by means of the Simha equation, using the assumption of unhydrated prolate ellipsoids as molecular models, vary from 9.9 to 16.3, these values depending on the buffer ion present, the conditions of equilibration, and the concentration of urea. There appears to be a slight change in configuration to a more spherical molecule on removal of salts from the urea solutions and on reduction of the urea concentration.