PEth in review: Phosphatidylethanol discovery and LC-MS/MS analysis.

The objective of this manuscript is to provide contextual information about the clinical ethanol biomarker phosphatidylethanol and evaluate contemporary analysis methods, mainly analysis by LC-MS/MS. The first part of the manuscript includes information regarding discovery, characterization, and result interpretation guidance relevant to the use of phosphatidylethanol as a clinical biomarker of ethanol ingestion. After this foundation information is discussed, various published analysis methods are reviewed and compared. Particular attention is paid to considerations for whole blood sample preparation and LC-MS/MS analysis conditions, including information regarding stability of PEth and a brief overview of dried-blood spot analysis. Lastly, special considerations relevant to the analysis of an endogenous, abnormal phospholipid are highlighted.