GC-MS Analysis of Plasma Metabolites

Plasma samples were derivatized and analyzed by gas chromatography-mass spectrometry (GC/MS) using TRACE 1310 GC system connected to TSQ8000 triple quad (Thermo Fisher Scientific, Bremen, Germany) as described previously (Marczak et al., 2021 (link)). The identified compounds were quantified by applying extracted ion chromatograms (EIC) based on selected m/z values and retention times corresponding to specific compounds. The unique masses were chosen based on NIST library spectra and EIC peaks were integrated to measure their areas. The total ion current was measured by integrating all TIC peaks and used for compounds normalization.