Column Selectivity - Theory of Column Chromatography

 Column Selectivity

The relative selectivity of a chromatographic column for a pair of solutes is given by the selectivity factor, α, which is defined as


The identities of the solutes are defined such that solute A always has the smaller retention time. Accordingly, the selectivity factor is equal to 1 when the solutes elute with identical retention times, and is greater than 1 when tr,B is greater than tr,A.

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