[Hartungen2004]
von Hartungen, E., A. Wisthaler, T. Mikoviny, D. Jaksch, E. Boscaini, P. J. Dunphy, and T. D. Märk,
"Proton-transfer-reaction mass spectrometry (PTR-MS) of carboxylic acids: Determination of Henry's law constants and axillary odour investigations",
International Journal of Mass Spectrometry, vol. 239, no. 2: Elsevier, pp. 243–248, 2004.
Link:
http://www.sciencedirect.com/science/article/pii/S1387380604003902
Proton-transfer-reaction mass spectrometry (PTR-MS) was used as an analytical tool to measure gas-phase concentrations of short-chain fatty acids. Chemical ionisation of C2single bondC6 carboxylic acids by PTR-MS produced intense protonated molecular ions (with traces of hydrates) along with acylium ion fragments. Gas-phase concentrations were derived using the established method for calculating PTR-MS sensitivity factors. Henry's law constants of carboxylic acids for aqueous solutions at 40 °C were determined. Direct monitoring of volatile fatty acids, known to be associated with secretions from the human axilla, was performed via a specially designed transfer device situated in the axilla. Mass spectral data corresponded with the findings of a sensory assessor.