Phenylglyoxal and glyoxal as fluorogenic reagents selective for N-terminal tryptophan-containing peptides

✍ Scribed by Eijiro Kojima; Yoshihito Ohba; Masaki Kai; Yosuke Ohkura

• Book ID: 102984197
• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 516 KB
• Volume: 280
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(93)80253-h

✦ Synopsis

Methods are described for the determination of N-terminal tryptophan-containing peptides in which phenylglyoxal and glyoxal are used as fluorogenic reagents. Phenylglyoxal and glyoxal react selectively with the peptides when heated in a strongly acidic medium in the presence of potassium hexacyanoferrate(II1) and in a moderately acidic medium, respectively, at 108°C for 30 min to produce fluorescence. The detection limits of N-terminal tryptophancontaining small peptides tested are 118-165 pmol ml-' in the reaction mixtures. The reaction mixture of tryptophylalanine, a model peptide, with glyoxal afforded a single peak when separated by reversed-phase liquid chromatography whereas that with phenylglyoxal gave several peaks.