Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1210859 | Journal of Chromatography A | 2008 | 9 Pages |
Abstract
This work demonstrates coupling of the newly described electrophoretic enrichment technique of gradient elution isotachophoresis (GEITP) to a low-cost, conventional ultraviolet absorbance detector to realize sensitive measurements with a universal detector, eliminating the need for fluorescent analytes or derivatization. The effects of various parameters on enrichment were studied, including current density varied by leading electrolyte concentration, current density varied by applied electric field, and counter-flow acceleration across varying capillary inner diameters. Optimized parameters were applied to the enrichment and separation of the amino acids tryptophan (Trp) and tyrosine (Tyr). Limits of detection for Trp and Tyr were 51 and 215Â nM, respectively, reflecting sensitivity enhancements of 860- and 1900-fold. Analysis times were less than 6Â min, and peak height RSDs were less than 4%. A demonstration of enrichment and separation of these amino acids from artificial cerebrospinal fluid is additionally shown as a first step to realizing biochemical monitoring by GEITP.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Manasa Mamunooru, Ronald J. Jenkins, Nejea I. Davis, Jonathan G. Shackman,