Persson J, Nasholm T
A GC-MS method for determination of amino acid uptake by plants
Physiol Plant: 2001 113:352-358
In this study, we present a rapid, robust and sensitive method for quantification of plant amino acid uptake using universally (U) (13C, 15N)-labelled amino acids and gas chromatography-mass spectrometry (GC-MS). Amino acids were analysed as their tert-butyldimethylsilyl (tBDMS) derivatives and displayed detection limits in the range 10-100 fmol on column, depending on the amino acid. The technique allows for simultaneous detection and quantification of both unlabelled and isotopically labelled species of amino acids. This makes simple quantification of plant amino acid uptake from an isotopically labelled source possible. The analytical variation was low, concerning total amino acid concentrations (relative standard deviation, rsd, less than 5.3%) as well as enrichment of U-13C, 15N-labelled glycine (Gly), arginine (Arg) and glutamic acid (Glu) (rsd