Quantitative Metrics to Properly Describe Solute Elution in Size-Exclusion Chromatography

Many different terms and definitions are used to explain the elution and the rate of retention/exclusion/retardation of an analyte in a chromatographic phase system. Size-exclusion chromatography is probably the most challenging chromatographic mode in terms of nomenclature, terms and metrics, with different terms sometimes being used incorrectly. The purpose of this short tutorial article is to review the terms and official nomenclatures for size-exclusion separations and to provide some guidance and recommendations for practicing chromatographers. The interconversion between the different metrics is explained and some examples are presented.