National Research Council of Canada. Aquatic and Crop Resource Development
National Research Council of Canada
National Research Council of Canada. Measurement Science and Standards
Chains; Electrospray ionization; Fish; Glycerol; Ions; Lithium; Mass spectrometry; Oil wells; Spectrometry; Direct infusions; ESI tandem mass spectrometry; Oil analysis; Quantitative data; Tandem mass spectrometry; Triacylglycerols; Triple stage mass spectrometry; Oil shale
This study was undertaken to determine whether triple-stage mass spectrometry (MS3) could be employed to obtain quantitative and regioisomeric data from complex oil samples without the need for a chromatographic step in the analysis protocol. Lithium-7 trifluoroacetate and electrospray ionization were used to form lithium adducts of the triacylglycerols (TAG) in a fish oil sample. The first-generation precursor ion was the lithium-TAG adduct, the second-generation precursor ion was formed by loss of a neutral acid side chain in the first fragmentation. The ions used for analysis were formed in the second fragmentation by loss of the lactones of the acid side chains remaining after the first fragmentation. This analysis scheme provided quantitative and regioisomeric data without interference from TAG in the sample other than TAG with the same acyl carbon number, one more double bond, and two acyl side chains in common with the analyte. Even in this case a majority of the interferences could be estimated and compensated. Analysis of synthetic samples containing the fish oil matrix indicated that both absolute and relative quantitative data could be obtained with average errors of approximately 5 %. The method proved well suited to routine analyses of complex oil samples.
JAOCS, Journal of the American Oil Chemists' Society92, no. 3 (6 February 2015): 323–334.