Fig. 2From: Accurate and efficient amino acid analysis for protein quantification using hydrophilic interaction chromatography coupled tandem mass spectrometryQuantitation of individual amino acids upon hydrolysis using three different methods. 13C, 15N labeled amino acid standards were hydrolyzed and compared to an unhydrolyzed standard. *Cysteine was detected as cystine. D/N represents the combination of aspartate and asparagine detected as aspartate, E/Q represents the combination of glutamate and glutamine detected as glutamateBack to article page