title: Atmospheric Pressure Vaporization Mechanism for Coupling a Liquid Phase with Electron Ionization Mass Spectrometry.
abstract: A novel liquid chromatography-mass spectrometry (LC-MS) interfacing concept is presented and discussed. The new interface, called liquid-EI (LEI), is based on electron ionization (EI) but, differently from any previous attempt, the vaporization of solutes and mobile phase takes place at atmospheric pressure into a specifically designed region, called "vaporization microchannel", before entering the high-vacuum ion source. The interface is completely independent from the rest of the instrumentation and can be adapted to any gas chromatography/mass spectrometry (GC/MS) system, as an add-on for a rapid LC-MS conversion. Pressure drop and temperature gradient between LC and MS were considered to enhance the analyte response and reduce band broadening and/or solute carryovers. A fused silica liner, placed inside the vaporization microchannel, acts as an inert vaporization surface speeding up the gas-phase conversion of large molecules while lessening possible memory effects. The liner is easily replaceable for a quick and extremely simple interface maintenance. Proof of concept and detailed description of the interface are here presented.
authors.affiliation: LC-MS Laboratory, Department of Pure and Applied Sciences, University of Urbino , Urbino, Italy.
authors.forename: Veronica
authors.initials: V
authors.lastname: Termopoli
authors.affiliation: LC-MS Laboratory, Department of Pure and Applied Sciences, University of Urbino , Urbino, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Famiglini
authors.affiliation: LC-MS Laboratory, Department of Pure and Applied Sciences, University of Urbino , Urbino, Italy.
authors.forename: Pierangela
authors.initials: P
authors.lastname: Palma
authors.affiliation: LC-MS Laboratory, Department of Pure and Applied Sciences, University of Urbino , Urbino, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Piergiovanni
authors.affiliation: LC-MS Laboratory, Department of Pure and Applied Sciences, University of Urbino , Urbino, Italy.
authors.forename: Achille
authors.identifier: 0000-0002-6416-304X
authors.initials: A
authors.lastname: Cappiello