title: Gas chromatographic-mass spectrometric analysis of the tripeptide glutathione in the electron-capture negative-ion chemical ionization mode.
abstract: The dicarboxylic tripeptide glutathione (GSH) is the most abundant intracellular thiol. GSH analysis by liquid chromatography is routine. Yet, GSH analysis by gas chromatography is challenged due to thermal instability and lacking volatility. We report a high-yield laboratory method for the preparation of (2)H-labeled GSH dimethyl ester ((d3Me)2-GSH) for use as internal standard (IS) which was characterized by LC-MS/MS. For GC-MS analysis, the dimethyl esters of GSH and the IS were derivatized with pentafluoropropionic (PFP) anhydride. Electron-capture negative-ion chemical ionization of the (Me)2-(PFP)3-GSH provided high sensitivity. We encourage increasing use of GC-MS in the analysis of amino acids as their Me-PFP derivatives in the ECNICI mode.
authors.affiliation: Bioanalytical Research Laboratory for NO, Oxidative Stress and Eicosanoids, Centre of Pharmacology and Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany. tsikas.dimitros@mh-hannover.de.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Tsikas
authors.affiliation: Bioanalytical Research Laboratory for NO, Oxidative Stress and Eicosanoids, Centre of Pharmacology and Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
authors.forename: Erik
authors.initials: E
authors.lastname: Hanff
authors.affiliation: Bioanalytical Research Laboratory for NO, Oxidative Stress and Eicosanoids, Centre of Pharmacology and Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
authors.forename: Arslan Arinc
authors.initials: AA
authors.lastname: Kayacelebi
authors.affiliation: Bioanalytical Research Laboratory for NO, Oxidative Stress and Eicosanoids, Centre of Pharmacology and Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
authors.forename: Anke
authors.initials: A
authors.lastname: Böhmer
mesh_terms: D004952:Esters; D005466:Fluorocarbons / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D005978:Glutathione / Q000032:analysis*; D007477:Ions
chemical_list: D004952:Esters; D005466:Fluorocarbons; D007477:Ions; C068048:pentafluoropropionic anhydride; D005978:Glutathione
keywords: Derivatization; Di[2H3-methylo]glutathione; Mass spectrometry; Stable-isotope dilution