SIZE-EXCLUSION CHROMATOGRAPHY DIMENSION FOR ROD-LIKE MACROMOLECULES

A phenomenological approach has been taken to determine the macromolecular dimension that controls peak migration in size-exclusion chromatography. For macromolecules representative of the class of rigid rods, flexible rods, random coils, and compact ellipsoids, the dependence of the chromatographic partition coefficient, KSEC, on the viscosity radius, the radius of gyration, and the contour length, respectively, was determined. Since none of these dimensions appears to control retention uniquely, a phenomenological definition of RSEC was provided. This parameter progressively deviates from the hydrodynamic radius with increasing macromolecular asymmetry. © 1990.