title: Preconcentration and frontal electroelution of amino acids for in-line solid-phase extraction–capillary electrophoresis
creator: Breadmore, MC
subject: 250000 Chemical Sciences
subject: 250401 Separation Science
subject: 250400 Analytical Chemistry
description: A new frontal electroelution approach that can be used for the preconcentration of amino acids in in-line solid-phase extraction–capillary electrophoresis (SPE–CE) has been developed. A single capillary was employed featuring a short monolithic SPE column created inside the capillary via photo-initiated, free-radical polymerisation of 3-sulfopropyl methacrylate and butyl methacrylate monomers. A weak electrolyte of dilute H2SO4, pH 2.9, was found to promote adsorption of the amino acids onto the SPE column. Elution of the amino acids was achieved using a dual solvation/ion-exchange transient boundary mobilised via EOF by using a strong electrolyte containing 62.5 mM ethylenediamine, pH 2.9 with H2SO4 and 40% (v/v) acetonitrile. Using these two electrolytes, tryptophan was adsorbed onto the SPE column in weak electrolyte and eluted via a frontal electroelution mechanism in the strong electrolyte. Injections up to 20 min, corresponding to over 14 column volumes (or 1400% of the capillary volume) of sample provided quantitative extraction of tryptophan from the weak electrolyte and were eluted without any loss in efficiency. This represents a practical increase of approximately 300-fold when compared to a typical hydrodynamic injection occupying 5% of the capillary volume.
date: 2006-01-18
type: Article
type: PeerReviewed
format: application/pdf
identifier: http://eprints.utas.edu.au/6635/1/029.pdf
relation: http://dx.doi.org/10.1016/j.aca.2005.07.069
identifier: Breadmore, MC (2006) Preconcentration and frontal electroelution of amino acids for in-line solid-phase extraction–capillary electrophoresis. Analytica Chimica Acta, 556 (1). pp. 121-126. ISSN 0003-2670
relation: http://eprints.utas.edu.au/6635/