ON SEPARATION MECHANISM OF GEL PERMEATION CHROMATOGRAPHY

The separation mechanism of gel permeation chromatography was investigated by static experiments. It was found that the solute molecule is excluded from part of the inner space of the gel particle, which is entirely available to the solvent molecule. The excluded volume, ΔV, increases with increase of molecular size of the solute. A linear relationship was observed between the ΔV and the logarithm of molecular size. Excluded volume was found to be independent of solute concentration as was expected. Absorption effect was negligible with polystyrene gel. However, a strong effect was observed between acids and polydextran gel. The possibility of using absorption effects to increase the separability of GPC is suggested. © 1968.