Determination of phenylalanine in serum using reversed-phase liquid chromatography and fluorescence detection.
A liquid chromatography procedure is reported for determining phenylalanine in small volumes of serum. A 10-microliter volume of serum was deproteinized with ethanol and an aliquot was derivatized with dansyl chloride reagent. The dansylated phenylalanine and the norleucine internal standard were separated using reversed-phase chromatography and measured with a fluorescence detector. Linearity was excellent over the range 50-800 mg/l. Within-run precision was better than 4%. Total analysis time including chromatography was approximately 40 min. As little as 300 pg of dansylated phenylalanine was detected.
D002853:Chromatography, Liquid / Q000379:methods*; D006801:Humans; D010649:Phenylalanine / Q000097:blood*; D010661:Phenylketonurias / Q000097:blood; D013050:Spectrometry, Fluorescence
D010649:Phenylalanine