Structural characterization of fatty acids with triple bond and unusual double bond positions by HPLC/APCI-MS2
2019
Abstract
Fatty acid methyl esters (FAMEs) were analyzed by reversed-phase HPLC coupled to atmospheric pressure chemical ionization (APCI) mass spectrometry. Acetonitrile was used as mobile phase.
The gasphase reactions of acetonitrile and unsaturated FAMEs in the APCI source provided [M + C H N]+⦁ adducts. Subsequent MS/MS analysis of these ions gave diagnostic fragments.
The formation and fragmentation of the acetonitrile-related adducts were utilized for the structural characterization of FAME with isolated double bonds in (Z)-9,19-hexacosadienoic acid methyl ester, FAME with conjugated double bonds in (Z)-9,11-octadecadienoic acid methyl ester and FAME with a triple bond in 9-octadecynoic acid methyl ester.