Transport diameters of liquid chromatography columns.

The transport diameter (dM) of a chromatographic column is an objective (measurable) representation of cross-sectional dimensions of the column flow-through channels, and of the effect of porosity of the column internal support structure on velocity of transporting solvent molecules along the column. A column kinetic performance is trade-off between the column separation performance, analysis time and pressure. The dM is a key factor in definition of the kinetic performance factor - an objective metric of a column kinetic performance - and of other objective performance metrics. General equations for evaluation of dM are developed. The dM of PLOT, particulate and pillar-array columns are evaluated and discussed.