Reversed-phase high-performance liquid chromatography coupled with second-order derivative spectroscopy for the quantitation of aromatic amino acids in peptides: application to hemorphins.

Q Zhao; F Sannier; I Garreau; C Lecoeur; J M Piot

doi:10.1016/0021-9673(95)00840-3

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Reversed-phase high-performance liquid chromatography coupled with second-order derivative spectroscopy for the quantitation of aromatic amino acids in peptides: application to hemorphins.

Q Zhao·F Sannier·I Garreau·C Lecoeur·J M Piot

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Abstract

The characterization of aromatic amino acid-containing peptides in biological fluids or protein hydrolysates is commonly achieved using classical size-exclusion (SE) and reversed-phase (RP) high-performance liquid chromatography (HPLC) coupled with direct ultraviolet (UV) spectrometry. Here, a non-destructive quantitative determination of aromatic amino acids in peptides is developed using second-order derivative spectra obtained during RP-HPLC coupled with photodiode array detection. In this method, the free aromatic amino acids were used as standards. Sensitivity and accuracy were verified using some peptides, including bioactive hemorphins. The method was applied to determine the amounts of hemorphins present in a complex peptic bovine hemoglobin hydrolysate.

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Amino Acid Sequence Amino Acids Animals Cattle Chromatography, High Pressure Liquid Hemoglobins Molecular Sequence Data Peptide Fragments Sensitivity and Specificity Spectrophotometry, Ultraviolet Journal Article Research Support, Non-U.S. Gov't

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Q Zhao, F Sannier, I Garreau, C Lecoeur, J M Piot. 1996-02-02. Reversed-phase high-performance liquid chromatography coupled with second-order derivative spectroscopy for the quantitation of aromatic amino acids in peptides: application to hemorphins.. https://doi.org/10.1016/0021-9673(95)00840-3

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