Determination of Amino Acids in Plasma Samples of Preeclampsia Patients by Liquid Chromatography Coupled to High-Resolution Mass Spectrometry

This work presents the application of a simple and sensitive method developed for the simultaneous analysis of the levels of twenty two underivatizated free L-amino acids in plasma samples of preeclampsia patients by high performance liquid chromatography coupled to high-resolution mass spectrometer (LC-HRMS) using hydrophilic interaction liquid chromatography (HILIC) silica column. The linearity was evaluated in the range of 0.009 to 8.018 µmol L-1 showing coefficients of determination (R2) in the range of 0.999 to 0.911 (p < 0.05). The intra- and inter-day precisions were above of 9.84 and 15.31, respectively. The limits of detection (LOD) and quantification (LOQ) were in the range of 0.003 to 0.683 µmol L-1 and 0.009 to 2.276 µmol L-1, respectively. The results of the investigation of free L-amino acids showed that the levels of GABA, Arg, Ser, Leu, Ile, Met, Val, Ala, Gly, Bet, His and Lys in plasma of patients with preeclampsia were significantly different from healthy patients.