Analysis of physiological amino acids using dabsyl derivatization and reversed-phase liquid chromatography.

A method is described for the measurement of the specific radioactivity of primary amino acids in physiological samples. The amino acids were dabsylated followed by separation using high-performance liquid chromatography. We measured the concentration of amino acids from rat plasma or liver samples. Chromatographic analyses resolved phenylalanine from a mixture of amino acids in plasma within 30 min. An extended chromatographic gradient program completely separated all physiological amino acids within 75 min. This method is as sensitive as any current method of amino acid analysis and offers several advantages including (1) simple pre-column derivatization and (2) stability of derivatized samples.