title: Flow-through microvial facilitating interface of capillary isoelectric focusing and electrospray ionization mass spectrometry.
abstract: A capillary electrophoresis mass spectrometry (CE-MS) interface utilizing a flow-through microvial is used to ensure the electric continuity and supply the catholyte and mobilizer solutions during the capillary isoelectric focusing (cIEF) and mobilization process. The flow-through microvial provides a stable chemical environment and helps to improve the ionization efficiency without significantly diluting the analyte. The CE-MS interface facilitates the transfer of the mobilized cIEF effluent to the site of electrospray ionization, and the gaseous ions can be detected directly by a mass spectrometer. It also allows for complete focusing and mobilization processes to be performed automatically in programmed sequences with commercial CE systems. Two different strategies, using either a part of the capillary or the flow-through microvial of the CE-MS interface as the catholyte reservoir for bare fused silica capillaries or neutral coated capillaries, respectively, were developed for automated cIEF-electrospray ionization (ESI)-MS. Reasonable separation efficiency was achieved using proper concentration of carrier ampholytes and suitable strategies of electroosmotic/electrophoretic mobilization.
authors.affiliation: Department of Chemistry, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Xuefei
authors.initials: X
authors.lastname: Zhong
authors.forename: E Jane
authors.initials: EJ
authors.lastname: Maxwell
authors.forename: Chitra
authors.initials: C
authors.lastname: Ratnayake
authors.forename: Scott
authors.initials: S
authors.lastname: Mack
authors.forename: David D Y
authors.initials: DD
authors.lastname: Chen
mesh_terms: D004573:Electrolytes / Q000737:chemistry; D019075:Electrophoresis, Capillary; D005990:Glycerol / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D004573:Electrolytes; D012822:Silicon Dioxide; D005990:Glycerol