Capillary zone electrophoresis separation of low concentration stimulants in human urine with laser-induced fluorescence detection

Capillary zone electrophoresis separation with laser-induced fluorescence (LEF) detection for the determination of fluorescein isothiocyanate (FITC) derivatized stimulants (ephedrine, phenylpropanolamine and heptaminol) was demonstrated. A simple electrophoretic buffer system composed of 30 mM triethylamine was selected and high voltage of 16 W was applied for the capillary electrophoresis separations. Stimulants in human urine were extracted by organic solvents and then derivatized with FITC. By employing a semiconductor laser-induced fluorescence detector, low concentration stimulants of 22 ng/mL can be detected within 10 min. Operation conditions for derivatization and separation were discussed. This simple CZE-LIF method with sensitive detection provided the possibility to develop the on-chip stimulants screening methods for doping control. (c) 2005 Published by Elsevier B.V.