title: Selective and sensitive determination of peptides using 3,4-dihydroxyphenylacetic acid as a fluorogenic reagent.
abstract: A novel fluorescence (FL) reaction for N-terminal Gly-containing peptides has been developed using 3,4-dihydroxyphenylacetic acid (3,4-DHPAA). The reaction of the peptides with 3,4-DHPAA was carried out in borate buffer (pH 8.0) in the presence of sodium periodate at 37°C for 10 min, and the FL was measured with a spectrofluorimeter at the excitation and emission wavelengths of 370 nm and 465 nm, respectively. The 3,4-DHPAA reagent generated particularly strong FL for peptides containing Gly at their N-termini. When various other bio-substances, such as amino acids, sugars, nucleic bases, nucleotides, and proteins, were reacted with 3,4-DHPAA, no FL was observed. Under optimized reaction conditions, the lower detection limit of 0.25 μmol L(-1) was obtained for the N-terminal Gly-containing peptides of Gly-Pro (GP) and Gly-Pro-Pro (GPP), which gave 3 times greater FL intensity than that observed for the reagent blank. The proposed reaction with 3,4-DHPAA as a fluorogenic reagent is selective and sensitive for the detection of N-terminal Gly-containing peptides, and therefore, this method could be a useful tool for the determination of these particular oligopeptides.
authors.affiliation: Faculty of Pharmaceutical Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Japan.
authors.forename: Hasina
authors.initials: H
authors.lastname: Yasmin
authors.forename: Takayuki
authors.initials: T
authors.lastname: Shibata
authors.forename: Mohammed Shafikur
authors.initials: MS
authors.lastname: Rahman
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Kabashima
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kai
mesh_terms: D015102:3,4-Dihydroxyphenylacetic Acid / Q000737:chemistry*; D000595:Amino Acid Sequence; D010455:Peptides / Q000032:analysis*; D010504:Periodic Acid / Q000737:chemistry; D013050:Spectrometry, Fluorescence
chemical_list: D010455:Peptides; D015102:3,4-Dihydroxyphenylacetic Acid; D010504:Periodic Acid; C009288:metaperiodate