Structural properties of macromolecular solutions

Abstract

We report measurements of viscosity and light scattering in an aqueous solution of BSA. Like the lysozyme solutions, previously investigated, the BSA solutions show thixotropic properties. Optical measurements of both elastic and inelastic light scattering indicate the existence of a structure in which the BSA molecule tends to clusterize, each cluster being correlated to the others. A k-dependent diffusion coefficient D(k) is found. The static structure factor deduced from the values of DL(k) agrees well with the indications given by the elastically scattered intensity 𝒥(k). Also, the statical properties of scattered light appear to be consistent with the proposed model. A qualitative explanation, in terms of a dominant component in the fluctuations of concentration, is briefly sketched.