1. The “n” nomenclature refers to the position of the double bond as counted from the methyl end of the carbon chain. While this is not the recommended nomenclature (that numbers bonds from the carboxylate end of the fatty acid) [2], it is instructive in this paper because the value of neutral loss due to chemically induced fragmentation in OzID spectra are common to lipids with double bonds at the same position in the chain with respect to the methyl terminus. For example, PC(16:0/18:1(9E)) and PC(16:0/20:1(11E)) have differing standard nomenclature but both are n-9 lipids and exhibit a common neutral loss in their OzID spectra.
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