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PubMed · 15456303

High-speed electrochemically modulated liquid chromatography.

Lisa M Ponton·Marc D Porter
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Abstract

The performance advantages of carrying out electrochemically modulated liquid chromatography (EMLC) at elevated temperatures and mobile-phase flow rates are investigated. EMLC has the unique ability to manipulate analyte retention and enhance separation efficiencies through changes in the potential applied to a conductive stationary phase. Operation of high-performance liquid chromatography systems at elevated column temperatures also provides pathways to improve chromatographic performance by enhancing analyte diffusivity and facilitating the use of higher mobile-phase flow rates than conventionally attainable. The results show that performing EMLC separations at elevated temperatures (e.g., 100 degrees C) reduces the analysis time of a mixture of aromatic sulfonates in a mixed mobile phase by more than a factor of 20. Moreover, use of higher operating temperatures enables the separation of this mixture with an entirely aqueous mobile phase in less than 2 min.

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Chromatography, High Pressure LiquidElectrochemistryTemperatureTime FactorsJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Lisa M Ponton, Marc D Porter. 2004-10-01. High-speed electrochemically modulated liquid chromatography.. https://doi.org/10.1021/ac049257w

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