title: A coaxially heated membrane introduction mass spectrometry interface for the rapid and sensitive on-line measurement of volatile and semi-volatile organic contaminants in air and water at parts-per-trillion levels.
abstract: A coaxially heated membrane introduction mass spectrometry (MIMS) sampling interface is presented that demonstrates improved on-line performance for the direct measurement of semi-volatile organic compounds (SVOCs) in air and water samples at parts-per-trillion levels. The device is based on a polydimethylsiloxane (PDMS) capillary hollow fibre membrane (HFM) in a pneumatically assisted "flow-over" configuration that is resistively heated on the membrane interior via a coaxial nichrome wire, establishing a thermal gradient counter to the analyte concentration gradient. This arrangement allows for continuous and/or pulsed heating modes, affording excellent sensitivity for the on-line measurement of SVOCs while retaining sensitivity for volatile organic compounds (VOCs). In addition, the signal response time for SVOCs is reduced substantially over conventional "flow-over" MIMS interfaces. Separation and quantitation of analytes are achieved using quadrupole ion trap tandem mass spectrometry.
authors.affiliation: Applied Environmental Research Laboratories, Department of Chemistry, Malaspina University-College, 900 Fifth Street, Nanaimo, British Columbia, Canada, V9R 5S5.
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Thompson
authors.forename: A Skye
authors.initials: AS
authors.lastname: Creba
authors.forename: Robyn M
authors.initials: RM
authors.lastname: Ferguson
authors.forename: Erik T
authors.initials: ET
authors.lastname: Krogh
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Gill