Dipeptide analysis in human urine.

Fractions of dipeptides, obtained from human urine by a combination of cation-exchange chromatography, ligand-exchange chromatography and reversed-phase chromatography, were transformed into their N-heptafluorobutyryl methyl ester derivatives and then subjected to capillary gas chromatography. The profiles obtained indicate the presence of many dipeptides in human urine. For the first time, alpha-Asp-Hyp, Pro-Phe and gamma-Glu-Phe were detected in the urine of healthy individuals.