Basic Structure-Independent Equations of Kinetic Performance of Columns in Liquid Chromatography
Leonid M. Blumberg
Abstract
The lowest dimensionless plate height (hmin) of the liquid chromatography (LC) column is a subjective metric that cannot be found from measurements of parameters of a column as a separation device and is not suitable for comparison of kinetic performance of differently structured columns. In some cases (monolithic, pillar-array columns), there is no correlation between hmin (as it is currently understood) and the column performance. The same is true for the flow resistance parameter (ϕ). Recently introduced measurable effective diameter and structural quality factor (qmax) of a column are objective replacements for ϕ and hmin. Metric qmax, the maximum of the flow-dependent kinetic performance factor (q), is suitable for comparison of differently structured columns. Structure-independent basic equations binding kinetic performance of LC column with its q and other parameters and operational conditions were developed. It has been shown that previously known and new equations of a column kinetic performance can be derived from the basic ones. An example of using the equations for solving a known practical problem of column selection is provided.