Separation MS

  • This section describes guidelines for various separation techniques, i.e.:
    • liquid chromatography, LC
    • gas chromatography, GC
    • supercritical fluid chromatography, SFC
    • ion mobility (IM)
  • Lipid species identification is based on principles discussed for for direct infusion MS
  • Retention time should be applied as an additional criteria for lipid species identification in chromatography-MS methods

Lipid class separation

  • LC, SFC: polar stationary phases – NP, HILIC
  • Retention times should match lipid class
  • Separation of isomeric lipid classes or isomeric lipid species need to be demonstrated by authentic standards

Lipid species separation

  • LC, SFC: non-polar stationary phases – RP
  • Retention times should match the structural features of the lipid species, i.e. content of DB, alkyl/acyl-bond
  • Separation of isomeric lipid species need to be demonstrated by authentic standards or substantiated by retention time models