title: Selected ion flow tube study of the reactions of H3O+and NO+with a series of primary alcohols in the presence of water vapour in support of selected ion flow tube mass spectrometry.
abstract: BACKGROUND
  Alcohols are often present in foods and other biological media, including exhaled breath, urine and cell culture headspace. For their analysis by selected ion flow tube mass spectrometry (SIFT-MS), the ion chemistry initiated by the reactions of the reagent ions H3O+and NO+with alcohol molecules in the presence of water molecules needs to be understood and quantitatively described.
  
  
  METHODS
  The reactions of H3O+and NO+ions have been studied with the primary alcohols, methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol and 1-hexanol, under the conditions used for SIFT-MS analyses (1 Torr He; 0.1 Torr air sample; 300 K) and over a range of sample gas humidity from 1% to 5.5%.
  
  
  RESULTS
  The H3O+reactions led to the formation of protonated alcohol molecules MH+and their hydrates MH+(H2O)1,2,3and (MH+-H2O) fragment ions. The NO+reactions were observed to proceed mainly via hydride ion transfer, resulting in the formation of [M-H]+product ions. Formation of the NO+M adduct ions was also observed due to ligand switching between the NO+(H2O)1,2hydrated reagent ions and M, and via direct NO+/M association in the case of ethanol. The variation in the percentages of the hydrated product ions with the air sample humidity is reported.
  
  
  CONCLUSIONS
  This detailed study has provided the kinetics data, including the secondary hydrated ion product distributions, for the reactions of a number of volatile primary alcohols with the SIFT-MS reagent ions H3O+and NO+, which allows their analyses by SIFT-MS in humid air and also helps in the interpretation of proton transfer reaction (PTR)-MS data. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, 182 23, Prague 8, Czech Republic.
authors.forename: Patrik
authors.initials: P
authors.lastname: Španěl
authors.affiliation: J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, 182 23, Prague 8, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Žabka
authors.affiliation: J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, 182 23, Prague 8, Czech Republic.
authors.forename: Illia
authors.initials: I
authors.lastname: Zymak
authors.affiliation: Institute for Science and Technology in Medicine, School of Medicine, Keele University, Thornburrow Drive, Hartshill, Stoke-on-Trent ST4 7QB, UK.
authors.forename: David
authors.initials: D
authors.lastname: Smith