LCGC Europe-11-01-2018

LCGC Europe

Vol 31 No 11 LCGC Europe November 2018 Regular Issue PDF

November 01, 2018

Issue PDF

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Click the title above to open the LCGC Europe November 2018 regular issue in an interactive PDF format.

Orthogonal Separation Techniques to Analyze (Very) Polar Molecules in Water Samples: Assessing SFC and Reversed-Phase LC–HILIC

November 01, 2018

Cover Story

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Supercritical fluid chromatography (SFC) and hydrophilic interaction liquid chromatography (HILIC) are suitable for screening very polar trace organic compounds in environmental water samples. The polarity range of separable compounds in SFC is as broad as the polarity range of the serial coupling of reversed‑phase liquid chromatography and HILIC (reversed-phase LC–HILIC). In this article the orthogonality of SFC and reversed-phase LC–HILIC is assessed. It is shown that both techniques are highly orthogonal and complementary. The parallel use of the two techniques offers additional benefits for the compound monitoring of, for example, pharmaceuticals in surface waters, or the identification of unknown compounds in complex samples.

Stationary Phase Selectivity: The Chemistry Behind the Separation

November 01, 2018

GC Connections

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“The column is the heart of the separation.” Perhaps more accurately, the column is where the chemistry that generates a separation happens. For chemists and non-chemists alike, the chemistry that drives the utility of a column to solve a separation problem can be complex and confusing. Selectivity describes the ability of a column to effect a separation. This instalment of “GC Connections” focuses on selectivity, its definition, and its importance for generating separations and resolution. We will also see how selectivity is the concept that underlies the idea of column polarity. We begin by asking two simple questions about common observations, then extend these observations into a capillary gas chromatography (GC) column, and conclude with an introduction to methods for evaluating the quality, selectivity, and polarity of a stationary phase or column.

Highlights from the HPLC 2018 Symposium

November 01, 2018

Column Watch

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The 47th International Symposium on High Performance Liquid Phase Separations and Related Techniques (HPLC 2018), chaired by Norman Dovichi, was held from 29 July to 2 August in Washington, D.C., USA. This instalment of “Column Watch” covers some of the highlights observed at the symposium. In addition, trends and perspectives on future developments in HPLC noted from the conference are presented.

HPLC Column Maintenance: Tips for Extending HPLC Column Lifetime

November 01, 2018

The Essentials

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Tips on how to extend high performance liquid chromatography (HPLC) column lifetimes.