Rapid monitoring of arrays of amino acids in clinical samples using capillary electrophoresis with contactless conductivity detection

CE with contactless conductivity detection has been used to separate 28 biogenic amino acids in a short capillary with an effective length of 18 cm. All the tested amino acids can be mutually separated in 0.5-10 mol/L acetic acid electrolytes. The time of analysis does not exceed 6 min and the LODs vary from 0.1 to 1.7 mu mol/L. The CVs lie within the intervals 0.01-0.4% and 0.9-4% for the migration times and the analyte peak areas, respectively. The procedure has been successfully applied to the determinations of the whole amino acid spectra in blood plasma, urine, saliva and cerebrospinal fluid samples.