Development and validation of a rapid, selective, and sensitive LC–MS/MS method for simultaneous determination of Emphasis Type='SmallCaps'd/Emphasis- and Emphasis Type='SmallCaps'l/Emphasis-amino acids in human serum: application to the study of hepatocellular carcinoma

摘要

Abstract A validated liquid chromatography–tandem mass spectrometry method was developed for the simultaneous determination of d - and l -amino acids in human serum. Under the optimum conditions, except for dl -proline, l -glutamine, and d -lysine, the enantioseparation of the other 19 enantiomeric pairs of proteinogenic amino acids and nonchiral glycine was achieved with a CROWNPAK CR-I(+) chiral column within 13 min. The lower limits of quantitation for l -amino acids (including glycine) and d -amino acids were 5–56.25 μM and 0.625–500 nM, respectively, in human serum. The intraday precision and interday precision for all the analytes were less than 15, and the accuracy ranged from ?12.84 to 12.37 at three quality control levels. The proposed method, exhibiting high rapidity, enantioresolution, and sensitivity, was successfully applied to the quantification of d - and l -amino acid levels in serum from hepatocellular carcinoma patients and healthy individuals. The serum concentrations of l -arginine, l -isoleucine, l -aspartate, l -tryptophan, l -alanine, l -methionine, l -serine, glycine, l -valine, l -leucine, l -phenylalanine, l -threonine, d -isoleucine, d -alanine, d -glutamate, d -glutamine, d -methionine, and d -threonine were significantly reduced in the hepatocellular carcinoma patients compared with the healthy individuals ( P d -Glutamate and d -glutamine were identified as the most downregulated serum markers (fold change greater than 1.5), which deserves further attention in hepatocellular carcinoma research. Graphical abstract Simultaneous determination of d - and l -amino acids in human serum from hepatocellular carcinoma patients and healthy individuals. AA amino acid, HCC hepatocellular carcinoma, LC liquid chromatography, MS/MS tandem mass spectrometry, NC normal control, TIC total ion chromatogram