title: Quantitative real-time monitoring of chemical reactions by autosampling flow injection analysis coupled with atmospheric pressure chemical ionization mass spectrometry.
abstract: Although qualitative and/or semiquantitative real-time monitoring of chemical reactions have been reported with a few mass spectrometric approaches, to our knowledge, no quantitative mass spectrometric approach has been reported so far to have a calibration valid up to molar concentrations as required by process control. This is mostly due to the absence of a practical solution that could well address the sample overloading issue. In this study, a novel autosampling flow injection analysis coupled with an atmospheric pressure chemical ionization mass spectrometry (FIA/APCI-MS) system, consisting of a 1 μL automatic internal sample injector, a postinjection splitter with 1:10 splitting ratio, and a detached APCI source connected to the mass spectrometer using a 4.5 in. long, 0.042 in. inner diameter (ID) stainless-steel capillary, was thus introduced. Using this system together with an optional FIA solvent modifier, e.g., 0.05% (v/v) isopropylamine, a linear quantitative calibration up to molar concentration has been achieved with 3.4-7.2% relative standard deviations (RSDs) for 4 replicates. As a result, quantitative real-time monitoring of a model reaction was successfully performed at the 1.63 M level. It is expected that this novel autosampling FIA/APCI-MS system can be used in quantitative real-time monitoring of a wide range of reactions under diverse reaction conditions.
authors.affiliation: Mass Spectrometry Center, Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996-1600, United States.
authors.forename: Zhenqian
authors.initials: Z
authors.lastname: Zhu
authors.forename: John E
authors.initials: JE
authors.lastname: Bartmess
authors.forename: Mary Ellen
authors.initials: ME
authors.lastname: McNally
authors.forename: Ron M
authors.initials: RM
authors.lastname: Hoffman
authors.forename: Kelsey D
authors.initials: KD
authors.lastname: Cook
authors.forename: Liguo
authors.initials: L
authors.lastname: Song
mesh_terms: D000181:Acrylonitrile / Q000737:chemistry; D001274:Atmospheric Pressure; D001331:Automation; D002138:Calibration; D017022:Flow Injection Analysis; D010627:Phenethylamines / Q000032:analysis; D011437:Propylamines / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation / Q000379:methods* / Q000592:standards
chemical_list: D010627:Phenethylamines; D011437:Propylamines; D012997:Solvents; C029261:phenethylamine; D000181:Acrylonitrile; C035263:2-propylamine