GRADIENT HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC ANALYSIS OF ENKEPHALIN PEPTIDES, THEIR METABOLITES AND ENZYME-INHIBITORS USING COMBINED ULTRAVIOLET AND ELECTROCHEMICAL DETECTION .1. OPTIMIZATION OF SEPARATIONAND DETECTION
Vp. Ranta et al., GRADIENT HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC ANALYSIS OF ENKEPHALIN PEPTIDES, THEIR METABOLITES AND ENZYME-INHIBITORS USING COMBINED ULTRAVIOLET AND ELECTROCHEMICAL DETECTION .1. OPTIMIZATION OF SEPARATIONAND DETECTION, Journal of chromatography, 766(1-2), 1997, pp. 85-97
Citations number
38
Categorie Soggetti
Chemistry Analytical","Biochemical Research Methods
Coulometric electrochemical detection (ED) was compatible with gradien
t HPLC analysis of enkephalin peptides, their metabolites and several
enzyme inhibitors with combined UV detection. The compounds were separ
ated using a reversed-phase octylsilane column with 35 mM phosphate bu
ffer (pH 2.1)-acetonitrile eluent. Hydrodynamic voltammograms were det
ermined for [D-Ala(2)]-methionine enkephalinamide (MEA) and its metabo
lites, and the response of MEA consisted of the oxidation of the tyros
ine and methioninamide residues with a total transfer of five electron
s at the highest potential used. Based on the voltammograms, ED was op
timized for the selective determination of MEA and other tyrosine-cont
aining peptides with detection limits between 0.4 and 0.6 pmol per 50
mu l injection. In addition, simultaneous UV detection at 205 nm allow
ed the determination of all the aromatic peptides and enzyme inhibitor
s with detection limits between 1.5 and 30.0 pmol.