Quantification of hydrolyzed peptides and proteins by amino acid fluorescence.

Reliable quantification of peptides and proteins is essential for drug discovery. We report the successful development and validation of an accurate and broadly applicable high performance liquid chromatography hyphenated to fluorescence detector procedure for the quantitative determination of the aromatic amino acids tyrosine, phenylalanine, and tryptophan, without relying on derivatization chemistry. Using ion-pair chromatography, fluorescent amino acids were clearly separated within 10 minutes.