Size-exclusion chromatography–multiangle laser light scattering analysis of β-lactoglobulin and bovine serum albumin in aqueous solution with added salt

The solution characteristics of β-LGB (β-lactoglobulin) and BSA (bovine serum albumin) are reported as determined by size-exclusion chromatography with on-line multiangle laser light scattering, differential refractive index and UV detection. The order of the three in series placed detectors as well as the interdetector volumes have been carefully pointed out. At concentrations below 2.5 mg/ml and at different values of pH the weight-average molecular mass of both proteins have been obtained. They indicate the appearance of monomers, dimers and higher order multimers. For β-LGB the growth of self-associates could be observed at the isoelectric point over a period of days. The range of applicability of the method is discussed.