Chromatographic-nuclear magnetic resonance can provide a prediction of high-pressure liquid chromatography shape selectivity tests

NMR diffusometry has been recently demonstrated as a means of investigating the mobility variations of solutes induced by chromatographic phases (under the acronym chromatographic-NMR). Particularly, a given compound has its average diffusivity reduced proportionally to its affinity towards the solid. In this work we propose the first comparison of chromatographic-NMR and tests for assessment of column performance, to investigate to what measure the novel approach could provide an assay of the outcome of a given stationary phase without the need of packing the relative column. Specifically, using bulk materials, we reproduce with very good agreement a shape selectivity test as reported in the catalog of a column producer, consisting of four probe molecules, applied to two different stationary phases.

► We analyze by NMR the changes in molecular mobility induced by chromatographic phases. ► We use this method to create the equivalent of a four PAHs shape selectivity test. ► Two RPLC column materials are analyzed. ► NMR results correlate very well with their LC correspondent.