Trimethylaminoethyl ester derivatization and stable isotope derivatization for enhanced analysis of fatty acids in biological samples by electrospray ionization tandem mass spectrometry
Liu Yang , Qingchun Wang , Weiwei Chen , Ji Yang , Yu Lin , David M. Lubman
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引用次数: 0
Abstract
Background
Abnormal fluctuations in free fatty acids (FFAs) are associated with cardiovascular diseases. However, conducting a thorough analysis of individual FFAs via mass spectrometry has historically posed challenges due to their low ionization efficiency and the absence of distinctive fragment ions.
Results
In this study, we introduce a method utilizing paired stable isotope derivatization coupled with liquid chromatography–triple quadrupole mass spectrometry (ID-LC-QQQ-MS) for thorough identification and relative quantification of fatty acids in serum samples. This method involves the derivatization of the carboxyl groups of FFAs using a pair of isotope reagents, resulting in the formation of FA trimethylaminoethyl ester (FA-TMAE-h3/d3), which can yield two distinct neutral fragments with masses of 59 and 62 Da during collision-induced dissociation (CID). Consequently, a quadruple neutral loss scan (QNLS) approach was utilized for the non-targeted profiling of FFAs in serum samples. The derivative peak pairs displaying matching retention times and distinct mass differences were extracted from the two QNLS spectra and recognized as potential FFAs. Subsequently, a multiple reaction monitoring (MRM) detection protocol was established for the relative quantification of fatty acids in the serum of Syrian Golden Hamsters subjected to various treatments, utilizing a pooled sample labeled with a heavy isotope as an internal standard. Partial least squares discriminant analysis (PLS-DA) revealed notable variations in these 23 fatty acids across the four groups.
Significance
The current stable isotope derivatization (ID) method, in conjunction with tandem mass spectrometry (MS/MS) analysis, stands out as a promising approach for identifying and quantifying FFAs in real samples.
期刊介绍:
The Journal of Chromatography B publishes papers on developments in separation science relevant to biology and biomedical research including both fundamental advances and applications. Analytical techniques which may be considered include the various facets of chromatography, electrophoresis and related methods, affinity and immunoaffinity-based methodologies, hyphenated and other multi-dimensional techniques, and microanalytical approaches. The journal also considers articles reporting developments in sample preparation, detection techniques including mass spectrometry, and data handling and analysis.
Developments related to preparative separations for the isolation and purification of components of biological systems may be published, including chromatographic and electrophoretic methods, affinity separations, field flow fractionation and other preparative approaches.
Applications to the analysis of biological systems and samples will be considered when the analytical science contains a significant element of novelty, e.g. a new approach to the separation of a compound, novel combination of analytical techniques, or significantly improved analytical performance.