Capillary electrophoresis with a UV light-emitting diode source for chemical monitoring of native and derivatized fluorescent compounds

Suminda Hapuarachchi, Gordon A. Janaway, Craig A. Aspinwall

Research output: Contribution to journalArticle

23 Scopus citations


We report the utilization of a high power UV light-emitting diode for fluorescence detection (UV-LED-IF) in CE separations. CE-UV-LED-IF allows analysis of a range of environmentally and biologically important compounds, including PAHs and biogenic amines, including neurotransmitters, amino acids, proteins, and peptides, that have been derivatized with UV-excited fluorogenic labels, e.g., o-phthalic dicarbox-aldehyde/ β-mercaptoethanol (OPA/β-ME). The 365 nm UV-LED was used as a stable, low cost source for detection of UV-excited fluorescent compounds. UV-LED-IF was used with both zonal CE separations and MEKC. Native fluorescence detection of PAHs was accomplished with detection limits ranging from 10 nM to 1.3 μM. Detection limits for OPA/ β-ME-labeled glutamic acid and aspartic acid were 11 and 10 nM, respectively, for off-line labeling, and 47 and 47 nM, respectively, for on-line labeling, comparable to UV-laser-based systems. Analysis of OPA/ β-ME-labeled proteins and peptides was performed with 28 and 47 nM detection limits for BSA and myoglobin, respectively.

Original languageEnglish (US)
Pages (from-to)4052-4059
Number of pages8
Issue number20
StatePublished - Oct 1 2006



  • Amino acids
  • Capillary electrophoresis
  • Chemical monitoring
  • Fluorescent detection
  • Light-emitting diode

ASJC Scopus subject areas

  • Analytical Chemistry
  • Biochemistry
  • Clinical Biochemistry

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