title: Design and applications of a self-aligning liquid junction-electrospray interface for capillary electrophoresis-mass spectrometry.
abstract: A simple self-aligning liquid junction-electrospray interface for coupling a capillary electrophoresis (CE) system to an atmospheric pressure ionization (API) mass spectrometer (CE-MS) was developed. In contrast to previous liquid junction interfaces, the self-aligning liquid junction interface simplifies the precise alignment of the CE capillary and the sprayer needle and uses a positive make-up flow. Several capillary CE-MS applications were run using both the self-aligning liquid junction interface and the widely used sheath flow interface for comparison purposes. The electrospray stability of the self-aligning liquid junction interface is consistently better even when non-volatile electrolyte solutions are used. At first, some band broadening was obtained with the self-aligning liquid junction interface. Experiments with different CE buffer systems suggested that this band broadening was caused by the materials used in constructing the interface. By using a more inert material for the sprayer needle, the self-aligning liquid junction exhibits excellent electrophoretic resolution, comparable sensitivity, and higher signal-to-noise ratios when run under the same conditions as the sheath flow interface.
authors.affiliation: Analytical Toxicology, Diagnostic Laboratory, Cornell University, Ithaca, NY 14850, USA.
authors.forename: T
authors.initials: T
authors.lastname: Wachs
authors.forename: R L
authors.initials: RL
authors.lastname: Sheppard
authors.forename: J
authors.initials: J
authors.lastname: Henion
mesh_terms: D000318:Adrenergic beta-Agonists / Q000737:chemistry / Q000652:urine*; D000420:Albuterol / Q000737:chemistry / Q000652:urine; D002976:Clenbuterol / Q000737:chemistry / Q000652:urine; D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods*; D004809:Ephedrine / Q000737:chemistry / Q000652:urine; D005280:Fenoterol / Q000737:chemistry / Q000652:urine; D007545:Isoproterenol / Q000737:chemistry / Q000652:urine; D013058:Mass Spectrometry / Q000295:instrumentation / Q000379:methods*; D009921:Metaproterenol / Q000737:chemistry / Q000652:urine; D013726:Terbutaline / Q000031:analogs & derivatives / Q000737:chemistry / Q000652:urine
chemical_list: D000318:Adrenergic beta-Agonists; D005280:Fenoterol; D009921:Metaproterenol; C010809:tulobuterol; D004809:Ephedrine; D007545:Isoproterenol; D013726:Terbutaline; D000420:Albuterol; D002976:Clenbuterol