Use of 4-(N,N-dimethylaminosulphonyl)-7-fluoro-2,1,3-benzoxadiazole as a labelling reagent for peroxyoxalate chemiluminescence detection and its application to the determination of the beta-blocker metoprolol in serum by high-performance liquid chromatography.
Fluorogenic reagents having a benzofurazan moiety, viz., 4-(N,N-dimethylaminosulphonyl)-7-fluoro-2,1,3-benzoxadiazole (DBD-F), 7-fluoro-4-nitro-2,1,3-benzoxadiazole and 4-(aminosulphonyl)-7-fluoro-2,1,3-benzoxadiazole, were compared for the sensitive analysis of their derivatives by high-performance liquid chromatography with peroxyoxalate chemiluminescence detection. Of the proline derivatives, DBD-proline was the most sensitive with a detection limit of 2 fmol. The optimum concentrations of bis[4-nitro-2-(3,6,9-trioxadecyloxycarbonyl)phenyl] oxalate and H2O2 for the post-column reaction were 0.5 and 75 mmol dm-3 respectively and amino acids and beta-blockers derivatized with DBD-F were detected in the range 0.2-40 fmol (signal-to-noise ratio = 3) using the proposed method. The lower detection limit of metoprolol (a beta-blocker having an isopropylamino group) spiked in serum was 0.8 ng ml-1 using 20 microl of serum (signal-to-noise ratio = 5).
Uzu
S
S
Branch Hospital Pharmacy, University of Tokyo, Japan.
Imai
K
K
Nakashima
K
K
Akiyama
S
S
D002851:Chromatography, High Pressure Liquid / Q000379:methods; D006801:Humans; D007202:Indicators and Reagents; D049449:Luminescence; D008790:Metoprolol / Q000097:blood*; D010070:Oxalates; D010080:Oxazoles; D013449:Sulfonamides
D007202:Indicators and Reagents; D010070:Oxalates; D010080:Oxazoles; D013449:Sulfonamides; C044622:peroxyoxalate; C060548:4-(N,N-dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole; D008790:Metoprolol