title: Sheathless capillary electrophoresis-mass spectrometry using a pulsed electrospray ionization source.
abstract: A sheathless interface has been developed for coupling CE with electrospray IT mass spectrometer. This interface utilized a pulsed ESI source. The use of a pulsed electrospray source allows the use of a sprayer with larger orifice, and thus alleviates the problem of column clogging during conductive coating and CE analysis. A pulsed ESI source operated at 20 Hz and 20% duty cycle was found to produce the optimal signals. For better signals, the maximum ion injection time in the IT mass spectrometer has to be set to a value close to the actual spraying time (10 ms). Using a sprayer with 50 microm od, more stable and enhanced signals were obtained in comparison with continuous CE-ESI-MS under the same flow rate (150 nL/min). The utility of this design is demonstrated with the analysis of synthetic drugs by CE-MS.
authors.affiliation: Department of Chemistry, National Taiwan University, Taipei.
authors.forename: Bing-Fong
authors.initials: BF
authors.lastname: Chao
authors.forename: Chao-Jung
authors.initials: CJ
authors.lastname: Chen
authors.forename: Fu-An
authors.initials: FA
authors.lastname: Li
authors.forename: Guor-Rong
authors.initials: GR
authors.lastname: Her
mesh_terms: D019075:Electrophoresis, Capillary / Q000295:instrumentation*; D004364:Pharmaceutical Preparations / Q000032:analysis; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation*
chemical_list: D004364:Pharmaceutical Preparations