title: Improving sensitivity in microchip electrophoresis coupled to ESI-MS/MS on the example of a cardiac drug mixture.
abstract: A comprehensive study for a sensitivity optimization in MCE with mass spectrometric detection is presented. As a text mixture, we chose a mixture of the cardiac drugs propranolol, bisoprolol, lidocaine, procaine and studied the effect of different chip layouts and experimental parameters with the aim of achieving both high sensitivity in MS detection and adequate chip electrophoretic separation. An important aspect was a comparison of microfluidic layouts containing various sheath-flow channels with that avoiding sheath-flow junctions on-chip. We utilized glass chips with monolithically integrated nanospray emitter tips coupled dead volume-free to an IT mass spectrometer running in fragmentation mode (MS(n) ). With this setup, detection limits down to 0.6 ng/mL for the model compound propranolol were achieved.
authors.affiliation: Institut für Analytische Chemie, Universität Leipzig, Leipzig, Germany.
authors.forename: Fabian
authors.initials: F
authors.lastname: Schwarzkopf
authors.forename: Tobias
authors.initials: T
authors.lastname: Scholl
authors.forename: Stefan
authors.initials: S
authors.lastname: Ohla
authors.forename: Detlev
authors.initials: D
authors.lastname: Belder
mesh_terms: D002317:Cardiovascular Agents / Q000032:analysis* / Q000737:chemistry / Q000652:urine; D046209:Electrophoresis, Microchip / Q000295:instrumentation / Q000379:methods*; D004867:Equipment Design; D006801:Humans; D057230:Limit of Detection; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000295:instrumentation / Q000379:methods
chemical_list: D002317:Cardiovascular Agents
keywords: Glass chip; Mass spectrometry; Microchip electrophoresis; Monolithic emitter; Sensitivity