The use of size-exclusion chromatography for determination of pore dim
ensions of chromatography media is reviewed. It is noted that many res
earchers still use the simple but inaccurate method of treating the se
lectivity curve as a cumulative pore size distribution. An alternative
procedure for estimation of pore dimensions of media through iteratio
n of the apparent pore size distribution to yield elution data in agre
ement with experimental data for polymers of known hydrodynamic radius
using a simple spread sheet is presented. Data of apparent pore dimen
sions of some commercial media for aqueous size-exclusion chromatograp
hy is presented. The influence of various parameters, e.g., solute sha
pe, pore shape, method errors, etc., is discussed. It is concluded tha
t size-exclusion chromatography can not provide information about the
pore structure and, thus, the pore size obtained is dependent upon the
selected pore model.