Beyond the second virial coefficient: sedimentation equilibrium in highly non-ideal solutions

8 páginas, 4 figuras, 1 tabla -- PAGS nros. 167-174The general theory of sedimentation equilibrium (SE), applicable to mixtures of interacting sedimentable solutes at arbitrary concentration, is summarized. Practical techniques for the acquisition of SE data suitable for analysis are described. Experimental measurements and analyses of SE in concentrated protein solutions are reviewed. The method of non-ideal tracer sedimentation equilibrium (NITSE) is described. Experimental studies using NITSE to detect and quantitatively characterize intermolecular interactions in mixtures of dilute tracer species and concentrated proteins or polymers are reviewedG.R. acknowledges funds from Plan Nacional BIO2008-04778-C03-03 (Ministerio de Ciencia e Innovación, Spain), COMBACT S-BIO-0260/2006 (Comunidad de Madrid) and DIVINOCELL FP7 HEALTH-F3-2009-223431 (European Commission). Research of A.P.M. is supported by the Intramural Research Program of the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, US Department of Health and Human ServicesPeer reviewe