THE USE OF FLUORESCENT-PROBE MOLECULES FOR DETECTION IN CAPILLARY ELECTROKINETIC SEPARATIONS

On-column fluorescence labeling using hydrophobic probe molecules is d escribed for the enhancement of detection in capillary zone electropho resis (CZE) and micellar electrokinetic capillary chromatography (MECC ). Experimental details are presented for the detection of alkyl sulfa te surfactant/micelle systems using the probe 2-p-toluidinonaphthalene -6-sulfonate. Using this labeling scheme, laser fluorimetry is employe d to determine sodium dodecyl sulfate in a generic, commercial soap pr oduct. The influence of probe molecule concentration on calibration pl ots and analyte mobility is also presented. The utility of indirect de tection for MECC is demonstrated with the addition of 1-anilinonaphtha lene-8-sulfonate to the micellar mobile phase. A brief discussion of t he analytical merits of this mode of detection is presented.