Gas chromatography-coupled mass-spectrometer (GC-MS).

Manufacturer: Chromatec (Russia), model: Crystal 5000

Current protocol quantifies:

• proteinogenic amino acids (except arginine)
• non-proteinogenic amino acids (ornithine, cystine, cystathionine)
• glycolysis intermediates
• TCA cycle metabolites
• sugars (glycose, fructose, sucrose)
• nucleic basis and nucleosides
• m-inositol, niacin, taurine, cholesterol, phosphoglycerol, glycerol
• fatty acids

The protocol of sample preparation can be found in O. Fiehn (Curr. Protoc. Mol. Biol., 2016).