title: Chip-CE/MS using a flat low-sheath-flow interface.
abstract: A chip-CE/ESI/MS interface based on a low-sheath-flow design has been developed. A flat low-sheath-flow interface was fabricated to facilitate the coupling with a CE microchip. The interface consists of a PMMA reservoir block, a PMMA platform and a replaceable ESI sprayer. A CE interface was constructed by using a wire-assisted epoxy-fixing method to connect a 1.5 cm connecting capillary to the end of chip-CE channel. The opposite end of the connecting capillary was tapered to approximately 40 microm od to fit tightly inside the back end of a removable fused-silica capillary ESI sprayer, which was also tapered to give a 10 microm orifice. With this 1.5 cm connecting capillary, the sheath liquid flowed coaxially around the connecting capillary to create a low dead volume liquid junction at the interface between the connecting capillary and the ESI emitter. An advantage of the current design over existing chip-based CE/MS interfaces is that ESI emitter can easily be replaced. The analytical utility of this microdevice was demonstrated by the analysis of two synthetic mixtures: a series histamine antagonists and a mixture of synthetic peptides.
authors.affiliation: Department of Chemistry, National Taiwan University, Taipei, Taiwan.
authors.forename: Fu-An
authors.initials: FA
authors.lastname: Li
authors.forename: Ju-Li
authors.initials: JL
authors.lastname: Huang
authors.forename: Guor-Rong
authors.initials: GR
authors.lastname: Her
mesh_terms: D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods; D046209:Electrophoresis, Microchip / Q000295:instrumentation*; D004867:Equipment Design; D010455:Peptides / Q000032:analysis; D019904:Polymethyl Methacrylate / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation* / Q000379:methods; D013499:Surface Properties
chemical_list: D010455:Peptides; D019904:Polymethyl Methacrylate