1-1(Z)-Hexadecenyl-2-palmitoyl-d9-sn-glycero-3-PE is intended for use as an internal standard for the quantification of 1-1(Z)-hexadecenyl-2-palmitoyl-sn-glycero-3-PE by GC- or LC-MS. 1-1(Z)-Hexadecenyl-2-palmitoyl-sn-glycero-3-PE is a plasmalogen that contains 1(Z)-hexadecanoic acid and palmitic acid at the sn-1 and sn-2 positions, respectively.