title: Tetraalkylammonium halides as chemical standards for positive electrospray ionization with ion mobility spectrometry/mass spectrometry.
abstract: Chemical standards for positive ion mode electrospray ionization ion mobility spectrometry/mass spectrometry (ESI(+)-IMS/MS) are suggested. The low clustering tendency of tetraalkylammonium halides makes them ideal chemical standards for ESI(+)-IMS/MS. A homologous series of these compounds forms a useful external standard for instrument testing and resolution calibration of an IMS instrument. Selected homologues or a mixture of tetraalkylammonium halides can be used as mobility standards in the analytical runs. Absolute and relative reduced mobilities were calculated for C2--C8, C10 and C12 tetraalkylammonium halides. Absolute reduced mobilities in nitrogen were 1.88, 1.56, 1.33, 1.15, 1.02, 0.92, 0.84, 0.73, and 0.67 cm2 V(-1) s(-1), for C2--C8, C10 and C12 tetraalkylammonium halides, respectively. Relative reduced mobilities (relative to 2,6-di-tert-butylpyridine) for the same compounds were 1.20, 1.00, 0.855, 0.743, 0.658, 0.59, 0.54, 0.47, and 0.43, respectively.
authors.affiliation: Department of Chemistry, P.O. Box 55, FI-00014 University of Helsinki, Finland. jyrki.viidanoja@helsinki.fi
authors.forename: Jyrki
authors.initials: J
authors.lastname: Viidanoja
authors.forename: Alexey
authors.initials: A
authors.lastname: Sysoev
authors.forename: Alexey
authors.initials: A
authors.lastname: Adamov
authors.forename: Tapio
authors.initials: T
authors.lastname: Kotiaho
mesh_terms: D006219:Halogens / Q000032:analysis / Q000737:chemistry*; D008024:Ligands; D000644:Quaternary Ammonium Compounds / Q000032:analysis / Q000737:chemistry*; D012015:Reference Standards; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation / Q000379:methods*
chemical_list: D006219:Halogens; D008024:Ligands; D000644:Quaternary Ammonium Compounds