Analysis of amino acids by miniaturised isotachophoresis.
A method allowing the miniaturised isotachophoretic analysis of amino acids has been developed. To overcome the problems of carbonate contamination which occur when performing separations at alkaline pH levels glycolate was used as the leading ion. Addition of magnesium to the leading electrolyte as a counter species was found to improve the separations. The method has been used on a poly(methyl methacrylate) microdevice with integrated on-column conductivity detectors. The behaviour of a range of common amino acids was investigated and successful separations of up to seven amino acids were made. Good linearity was observed with calibration curves for aspartic acid and phenylalanine over the range 0.063-1.0 mM. Limits of detection for these two species were calculated to be 0.060 and 0.018 mM, respectively.
Prest
Jeff E
JE
Department of Instrumentation and Analytical Science, UMIST P.O. Box 88, Manchester, UK. j.prest@umist.ac.uk
Baldock
Sara J
SJ
Fielden
Peter R
PR
Goddard
Nicholas J
NJ
Brown
Bernard J Treves
BJ
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis*; D002138:Calibration; D004563:Electrochemistry; D004586:Electrophoresis / Q000379:methods*; D008904:Miniaturization; D012680:Sensitivity and Specificity; D013056:Spectrophotometry, Ultraviolet
D000596:Amino Acids