ABSTRACT
A method is presented for determining second virial coefficients (B(2)) of protein solutions from retention time measurements in size exclusion chromatography. We determine B(2) by analyzing the concentration dependence of the chromatographic partition coefficient. We show the ability of this method to track the evolution of B(2) from positive to negative values in lysozyme and bovine serum albumin solutions. Our size exclusion chromatography results agree quantitatively with data obtained by light scattering.
Subject(s)
Chromatography, Gel/methods , Flow Injection Analysis/methods , Muramidase/chemistry , Protein Interaction Mapping/methods , Serum Albumin, Bovine/chemistry , Algorithms , Macromolecular Substances , Muramidase/analysis , Protein Binding , Reproducibility of Results , Sensitivity and Specificity , Serum Albumin, Bovine/analysisABSTRACT
The axisymmetric deformation and motion of interacting droplets under the combined influence of the gravitational force and a vertical temperature gradient is considered using boundary-integral techniques for creeping flow. The focus is on the case when the net thermocapillary and buoyancy forces acting on the drops are directed oppositely. When these forces are almost balanced our analysis shows that, though the deformations of the drops are apparently small, their influence on the motion is considerable. For highly deformable drops moving in a gravity field, even a small temperature gradient that almost does not effect the drops velocity may drastically change the deformation pattern and prevent the drops from breakup.