Gradient elution electrochromatography with a flow-injection analysis interface.

A S Lister; C A Rimmer; J G Dorsey

doi:10.1016/s0021-9673(98)00682-7

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PubMed · 9916300

Gradient elution electrochromatography with a flow-injection analysis interface.

A S Lister·C A Rimmer·J G Dorsey

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Abstract

A flow-injection analysis-capillary electrochromatography interface is used for gradient elution capillary electrochromatography giving purely electroosmotic flow through the analytical column. Solvent gradients were generated with a micro-LC system connected to the interface. Injections were carried out on-line using an inert rotary LC valve controlled by an electric actuator. Gradient shape was measured from acetonitrile (5% acetone)-water (50:50, v/v) to (100:0) in open tubular experiments. When compared to conventional instrumentation, peak tailing and peak width increased slightly using the interface. A test mixture of nine solutes was evaluated in isocratic and gradient elution modes. Using the interface, a gradient of MeCN-water (60:40) to (90:10) provided baseline separation of all nine solutes in under 18 min with good band spacing. Reproducibility of retention times in eight replicate injections was found to be better than 2% R.S.D. for all solutes. This interface also allows use of autoinjectors and dramatically lessens movement of the packed column, improving column lifetime.

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Chromatography, High Pressure Liquid Electrophoresis, Capillary Flow Injection Analysis Reproducibility of Results Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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A S Lister, C A Rimmer, J G Dorsey. 1998-12-18. Gradient elution electrochromatography with a flow-injection analysis interface.. https://doi.org/10.1016/s0021-9673(98)00682-7

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