Optimization of the separation and on-line sample concentration of phenethylamine designer drugs with capillary electrophoresis-fluorescence detection

Chung Chen Tsai, Ju Tsung Liu, You Ren Shu, Po Han Chan, Cheng Huang Lin

Research output: Contribution to journalArticle

28 Citations (Scopus)


Five 2C-series of phenethylamine designer drugs, including 2,5-dimethoxy-4-ethylthio-phenethylamine (2C-T-2), 2,5-dimethoxy-4-(n)- propylthiophenethylamine (2C-T-7), 4-chloro-2,5-dimethoxyphenethylamine (2C-C), 4-bromo-2,5-dimethoxy-phenethylamine (2C-B), 2,5-dimethoxy-4-iodo-phenethylamine (2C-I), were synthesized and standard GC/MS and fluorescence spectra are reported for them. A mixture of the five drugs was separated and detected by means of capillary electrophoresis (CE) with native fluorescence and light emitting diode (LED)-induced fluorescence (LIF) detection, respectively, for comparison. In the former case, exciting at a wavelength of 300 nm from a Xe lamp was used. The detection limits were found to be only in the range of ∼10-4 M by the micellar electrokinetic chromatography (MEKC) mode but were improved to ∼10-7 M when the sweeping-MEKC mode was used. For a highly sensitive analysis, LED-induced fluorescence detection was examined by derivatizing the compounds with a fluorescent dye, fluorescein isothiocyanate isomer I (FITC). A blue-LED (∼2 mW) was used as the fluorescence excitation source. The detection limits were improved to ∼10-7 and ∼10-8 M, respectively, when the MEKC and stacking-MEKC modes were applied. A mimic urine sample was obtained by spiking urine from a volunteer with the five standards, and after liquid-liquid extraction, the sample was examined by means of the MEKC-LIF mode. The extraction procedures used for the urine sample and the CE conditions for the separation were optimized.

Original languageEnglish
Pages (from-to)319-323
Number of pages5
JournalJournal of Chromatography A
Issue number1-2
Publication statusPublished - 2006 Jan 6



  • 2C-B
  • 2C-C
  • 2C-I
  • 2C-T-2
  • 2C-T-7
  • Designer drugs
  • FITC
  • LED
  • LED-induced fluorescence (LIF)
  • Native fluorescence
  • Phenethylamine
  • Urine

ASJC Scopus subject areas

  • Analytical Chemistry
  • Biochemistry
  • Organic Chemistry

Cite this