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Column selectivity in reversed-phase liquid chromatography. VI. Columns with embedded or end-capping polar groups.

N S Wilson·J Gilroy·J W Dolan·L R Snyder
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Abstract

A previous model of column selectivity for reversed-phase liquid chromatography (RP-LC) has been applied to an additional 21 columns with embedded or end-capping polar groups (EPGs). Embedded-polar-group columns exhibit a significantly different selectivity vs. non-EPG, type-B columns, generally showing preferential retention of hydrogen-bond donors, as well as decreased retention for hydrogen-bond acceptors or ionized bases. EPG-columns are also generally less hydrophobic (more polar) than are non-EPG-columns. Interestingly, columns with polar end-capping tend to more closely resemble non-EPG columns, suggesting that the polar group has less effect on column selectivity when used to end-cap the column versus the case of an embedded polar group. Column selectivity data reported here for EPG-columns can be combined with previously reported values for non-EPG columns to provide a database of 154 different columns. This enables a comparison of any two of these columns in terms of selectivity. However, comparisons that involve EPG columns are more approximate.

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AcidsChromatography, LiquidHydrogen BondingHydrophobic and Hydrophilic InteractionsSensitivity and SpecificitySolubilityStatic ElectricityJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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N S Wilson, J Gilroy, J W Dolan, L R Snyder. 2004-02-13. Column selectivity in reversed-phase liquid chromatography. VI. Columns with embedded or end-capping polar groups.. https://doi.org/10.1016/j.chroma.2003.11.041

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