title: Violet light emitting diode-induced fluorescence detection combined with on-line sample concentration techniques for use in capillary electrophoresis.
abstract: The first application of a violet light-emitting diode (LED) for fluorescence detection in capillary electrophoresis (CE) is described. The utility of violet LED (peak emission wavelength at 410 nm, approximately 2 mW) for fluorescence detection is demonstrated by examining reserpine and dopamine-labeled NDA (naphthalene-2,3-dicarboxaldehyde), respectively. The detection limit for reserpine was determined to be 2.5 x 10(-6) M by normal micellar electrokinetic capillary chromatography (MEKC) and this was improved to 2.0 x 10(-9) M and 2.0 x 10(-10) M when sweeping-MEKC and cation-selective exhaustive injection (CSEI)-sweep-MEKC techniques were applied, respectively. In addition, the detection limit of NDA-labeled dopamine was determined to be 6.3 x 10(-6) M by means of normal MEKC and this was improved to 3.0 x 10(-8) M when the sweeping-MEKC mode was applied.
authors.affiliation: Department of Chemistry, National Taiwan Normal University, Taipei, Taiwan.
authors.forename: Chih-Hsin
authors.initials: CH
authors.lastname: Tsai
authors.forename: Hsuan-Ming
authors.initials: HM
authors.lastname: Huang
authors.forename: Cheng-Huang
authors.initials: CH
authors.lastname: Lin
mesh_terms: D002021:Buffers; D020374:Chromatography, Micellar Electrokinetic Capillary / Q000295:instrumentation / Q000379:methods*; D004298:Dopamine / Q000737:chemistry; D005453:Fluorescence; D007202:Indicators and Reagents; D008823:Micelles; D009281:Naphthalenes; D012110:Reserpine / Q000737:chemistry; D013997:Time Factors
chemical_list: D002021:Buffers; D007202:Indicators and Reagents; D008823:Micelles; D009281:Naphthalenes; C027717:2,3-naphthalenedicarboxaldehyde; D012110:Reserpine; D004298:Dopamine