Wm. Craig Byrdwell, phd

Resources for Lipid Analysis in the 21st Century

This is a Phosphatidyl Ethanolamine (PE) Plasmalogen molecule. This PE Plas contains a 20:4 (arachidonic acid) fatty acyl chain and a 1-O-alkenyl 18:0 (vinyl ether) chain. It is (p18:0/20:4)-PE Plas. Phosphatidyl Ethanolamine Plasmalogens form protonated molecules, [M+H]+, by electrospray ionization mass spectrometry (ESI-MS) and by atmospheric pressure chemical ionization mass spectrometry (APCI-MS).  They form deprotonated molecules, [M-H] by negative-ion ESI-MS and APCI-MS.  Plasmalogens often have long-chain polyunsaturated acyl chains.

Plasmalogens Home page

This page has been established to disseminate free copies of mass lists of Plasmalogens, or Alkenyl Phospholipids, as well as Alkanyl Phospholipids.  Plasmalogens have a ‘vinyl ether’ linkage, which is an oxygen atom next to a cis double bond on the alkenyl chain.  This combination of an ether oxygen plus a double bond is what makes Plasmalogens different from normal glycerophospholipids.  The vinyl ether linkage is found at the sn-1 carbon of the backbone.

According to F. Snyder [1]: “...ether linkages in phospholipids of mammalian cells exist almost exclusively in the choline and ethanolamine glycerolipid classes.”  “In phospholipids, the majority of the O-alkyl moieties generally occur as plasmanylcholines, whereas the O-alk-1-enyl grouping is mainly associated with the plasmenylethanolamines.”

Therefore, most Plasmalogens are PhosphatidylEthanolamine Plasmalogens, or PlasmenylEthanolamines.  On the other hand, PlasmanylCholines have  a quaternary amine head group and do not have the cis double bond on the first carbon of the alkyl chain at the  sn-1 position.  Nevertheless, masses for both Plasmalogens (plasmenylethanolamines) and plasmanylcholines are given here at Plasmalogens.com.

Mass lists from these pages pertain to analysis of Plasmalogens by atmospheric pressure chemical ionization (APCI)  and electrospray ionization (ESI) mass spectrometry (MS) techniques:


Data are given for protonated molecules, fragment ions analogous to diacylglycerols, and fatty acid-related fragments from Plasmalogens.

Mass lists are given as:

1.  Fatty Acid and Fatty Acid Methyl Ester mass list.

2.  PhosphatidylEthanolamine Plasmalogens & Fragment Masses by PE Plas name.

3.  PhosphatidylCholine Plasmalogens & Fragment Masses by PC Plas mass.

4.  Alkanyl PhosphatidylEthanolamine  masses by name.

5.  Alkanyl PhosphatidylCholine  masses by name.

These tables were put together by Dr. Byrdwell in the course of more than a decade of working on lipid analysis.

These mass lists are provided here as a service to my colleagues.


Please report any errors in these pages to Byrdwell@Byrdwell.com

To contact me:

Wm. Craig Byrdwell, Ph.D.

Beltsville, MD  20705


E-mail: Byrdwell@Byrdwell.com

Disclaimer:  Not all fragments or adducts listed here are observed from every class of phospholipid.  Most fragments have been listed here for the sake of thoroughness, whether they are actually observed or not.

Reference 1:

F. Snyder, “Ether-Linked Lipids and Their Bioactive Species: Occurrence, Chemistry, Metabolism, Regulation and Function”, in D.E. Vance and J. Vance (Eds.) Biochemistry of Lipids, Lipoproteins and Membranes, Elsevier, Amsterdam, The Netherlands, 1996

© 2005-2011

The figures and tables on this website are copyrighted in 2005-2011 by William Craig Byrdwell and Byrdwell.com.  Please reference



Disclaimer 2:  The information provided here is not approved by, sanctioned by or paid for by Dr. Byrdwell’s employer.  They are not responsible for its content.  Advertisements may appear on some pages to help defray the costs of website publication and maintenance.