Measuring the Content of Endocannabinoid-Like Compounds in Biological Fluids: A Critical Overview of Sample Preparation Methodologies.

Different mass spectrometric techniques have been used over the past decade to quantify endocannabinoids (eCBs) and related lipids. Even with the level of molecular fingerprinting accuracy of an instrument like the most advanced triple quadrupole mass spectrometer, if one is not getting the most optimized sample to the detector in a way that this improved technology can be of use, then advancements can be stymied. Here, our focus is on review and discussion of sample preparation methodologies used to isolate the eCB anandamide and its close congeners N-acyl ethanolamines and structural congeners (i.e., lipo amino acids, lipoamines, N-acyl amides) in biological fluids. Most of our focus will be on the analysis of these lipids in plasma/serum, but we will also discuss how the same techniques can be used for the analysis of saliva and breast milk.