Abstract
Axial dispersion in interparticle spaces and intra-gel diffusion are the two unknown factors to control the spreading of a pulse introduced in a dextran gel bed. Macromolecule (blue dextran) which is excluded by gel particle and small molecule (sodium chloride) are used together to separate these two contributions. Axial dispersion is of unusual significance, and intraparticle diffusivities of sodium chloride in Sephadex G-25 and G-50 are 1.55 × 10-6 and 1.5 × 10-5 cm2/sec at room temperature.