A LC-MS-based workflow for measurement of branched fatty acid esters of hydroxy fatty acids

Nat Protoc. 2016 Apr;11(4):747-63. doi: 10.1038/nprot.2016.040. Epub 2016 Mar 17.


Branched fatty acid esters of hydroxy fatty acids (FAHFAs) are a recently discovered class of endogenous mammalian lipids with antidiabetic and anti-inflammatory effects. We previously identified 16 different FAHFA families, such as branched palmitic acid esters of hydroxy stearic acids (PAHSAs); each family consists of multiple isomers in which the branched ester is at different positions (e.g., 5- and 9-PAHSA). We anticipate increased need for PAHSA measurements as markers of metabolic and inflammatory health. In this protocol, we provide a detailed description of the extraction of FAHFAs from human or mouse tissues, their enrichment by solid-phase extraction and subsequent analysis by LC-MS. For a sample size of 6-12, the time frame is 2-3 d.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chromatography, Liquid / methods*
  • Fatty Acids / analysis*
  • Fatty Acids / isolation & purification
  • Humans
  • Mass Spectrometry / methods*
  • Mice
  • Time Factors
  • Workflow


  • Fatty Acids