Abstract
We developed a new selective liquid chromatography–electrospray ionization-tandem mass spectrometry method for the identification and quantification of anandamide (AEA), an endogenous cannabinoid receptor ligand, and other bioactive fatty acid ethanolamides (FAEs) in biological samples. Detection limit (0.025 pmol for AEA and 0.1 pmol for palmitoylethanolamide (PEA) and oleoylethanolamide (OEA)) and quantification limit (0.2 pmol for AEA and 0.4 pmol for OEA and PEA) were in the high fmol to low pmol range for all analytes. Linear correlations ( r 2 = 0.99) were observed in the calibration curves for standard AEA over the range of 0.025–25 pmol and for standard PEA and OEA over the range of 0.1–500 pmol. This method provides a time-saving and sensitive alternative to existing methods for the analysis of FAEs in biological samples.
Highlights
Abbreviations usedAEA, anandamide; fatty acid ethanolamides (FAEs), fatty acid ethanolamide; PEA, palmitoylethanolamide; OEA, oleoylethanolamide; QCs, quality control samples; ESI, electrospray ionization; SRM, selected reaction monitoring
Endogenous cannabinoids, such as anandamide (AEA)1, and structurally related fatty acid ethanolamides (FAEs) play important roles as physiological modulators of numerous processes in the peripheral and central nervous system [1,2]
After stirring and phase separation, the upper aqueous phase was discarded and the organic phase was washed several times to remove remaining ethanolamine. This reaction results in the quantitative formation of FAEs, which were concentrated to dryness under stream of N2 and reconstituted in chloroform at a concentration of 20 mM
Summary
AEA, anandamide; FAE, fatty acid ethanolamide; PEA, palmitoylethanolamide; OEA, oleoylethanolamide; QCs, quality control samples; ESI, electrospray ionization; SRM, selected reaction monitoring. Gas chromatography (GC) and high performance liquid chromatography (HPLC) methods require derivatization steps during preparation since FAEs are nonvolatile, do not Xuoresce, and have weak UV absorption To overcome these limitations, we established a novel approach for the detection of AEA, PEA, and OEA in human serum: AEA and OEA were analyzed using silver cation coordination and positive electrospray tandem mass spectrometry, whereas, for the quantiWcation of PEA, which lacks a double bond to bind silver cations, we monitored the protonated species. We established a novel approach for the detection of AEA, PEA, and OEA in human serum: AEA and OEA were analyzed using silver cation coordination and positive electrospray tandem mass spectrometry, whereas, for the quantiWcation of PEA, which lacks a double bond to bind silver cations, we monitored the protonated species This new sensitive and selective method for determining AEA and its analogs allowed us to achieve higher sensitivity than previously published methods
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.