Interactions between the macromolecule and the gradient-forming solute in isopycnic sedimentation.

Interactions between the macromolecules and the gradient-forming solute in isopycnic sedimentation equilibrium experiments affect the distribution of the macromolecules in a number of ways. A description is given of the effects that may be expected, and some recently reported results are interpreted in the light of these. Suggestions are made for the recognition of such interactions, and for their possible effects, both good and bad, on experimental results.