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Introduction Mass Spectrometry (introduction + mass_spectrometry)
Kinds of Introduction Mass Spectrometry Selected AbstractsFiber introduction mass spectrometry: determination of pesticides in herbal infusions using a novel sol,gel PDMS/PVA fiber for solid-phase microextractionJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 6 2007Rogério Cesar da Silva Abstract An application of the direct coupling of solid-phase microextraction (SPME) with mass spectrometry (MS), a technique known as fiber introduction mass spectrometry (FIMS), is described to determine organochlorine (OCP) and organophosphorus (OPP) pesticides in herbal infusions of Passiflora L. A new fiber coated with a composite of poly(dimethylsiloxane) and poly(vinyl alcohol) (PDMS/PVA) was used. Sensitive, selective, simple and simultaneous quantification of several OCP and OPP was achieved by monitoring diagnostic fragment ions of m/z 266 (chlorothalonil), m/z 195 (,-endosulfan), m/z 278 (fenthion), m/z 263 (methyl parathion) and m/z 173 (malathion). Simple headspace SPME extraction (25 min) and fast FIMS detection (less than 40 s) of OCP and OPP from a highly complex herbal matrix provided good linearity with correlation coefficients of 0.991,0.999 for concentrations ranging from 10 to 140 ng ml,1 of each compound. Good accuracy (80 to 110%), precision (0.6,14.9%) and low limits of detection (0.3,3.9 ng ml,1) were also obtained. Even after 400 desorption cycles inside the ionization source of the mass spectrometer, no visible degradation of the novel PDMS/PVA fiber was detected, confirming its suitability for FIMS. Fast (ca 20 s) pesticide desorption occurs for the PDMS/PVA fiber owing to the small thickness of the film and its reduced water sorption. Copyright © 2007 John Wiley & Sons, Ltd. [source] Environmental applications of membrane introduction mass spectrometryJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 5 2002Raimo A. Ketola Abstract The purpose of this review is to highlight the versatility of membrane introduction mass spectrometry (MIMS) in environmental applications, summarize the measurements of environmental volatile organic compounds (VOCs) accomplished using MIMS, present developments in the detection of semi-volatile organic compounds (SVOCs) and forecast possible future directions of MIMS in environmental applications. Copyright © 2002 John Wiley & Sons, Ltd. [source] High surface area membrane introduction mass spectrometry for analysis of volatile and semi-volatile organic compounds in airRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 17 2001Leah S. Riter The construction, optimization, and testing of a novel geometry for a semi-permeable polydimethylsiloxane membrane introduction mass spectrometry (MIMS) system is described. A long poly(dimethylsiloxane) capillary membrane (0.30,mm i.d., 0.64,mm o.d., 60,cm long) was positioned coaxially inside polytetrafluoroethylene tubing (0.80,mm i.d. and 1.60,mm o.d.), allowing for a large surface area membrane of relatively small thickness. Helium, flowing counter-current on the vacuum side of the membrane, swept the permeate into the mass spectrometer. This optimized geometry for permeation MIMS air analysis allows on-line detection of volatile and semi-volatile organic compounds of environmental interest, with limits of detection in the ppt range and a linear response over 3 to 4 orders of magnitude. The system is characterized by short rise and fall times, 10 and 48,s, respectively, for toluene. Copyright © 2001 John Wiley & Sons, Ltd. [source] | ||||||||||