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The application of small porous particles, high temperatures, and high pressures to generate very high resolution LC and LC/MS separations

✍ Scribed by Robert Plumb; Jeff R. Mazzeo; Eric S. Grumbach; Paul Rainville; Michael Jones; Tom Wheat; Uwe D. Neue; Brian Smith; Kelly A. Johnson

Publisher: John Wiley and Sons
Year: 2007
Tongue: English
Weight: 617 KB
Volume: 30
Category: Article
ISSN: 1615-9306
DOI: 10.1002/jssc.200600492

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✦ Synopsis

Abstract

The effect of combining sub‐2 μm porous particles with elevated operating temperatures on chromatographic performance has been investigated in terms of chromatographic efficiency, productivity, peak elution order, and observed operating pressure. The use of elevated temperature in LC does not increase the obtainable performance but allows the same performance to be obtained in less time. Increasing the column temperature did allow the use of longer columns, generating column efficiencies in excess of 100 000 plates and gradient peak capacities approaching 1000. Raising the temperature increased the optimal mobile phase linear velocity, negating somewhat the pressure benefits observed by reducing the solvent viscosity. When operating at higher temperature the analyte retention is not only reduced, but the order of elution will also often change. High temperature separations allowed exotic organic modifiers such as isopropanol to be exploited for alternative selectivity and faster analysis. Finally, care must be taken when using high temperature separations to ensure that the narrow peak widths produced do not compromise the quality of data obtained from detectors such as high resolution mass spectrometers.

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