4-(N-hydrazinoformylmethyl-N-methyl)-amino-7-N, N-dimethylaminosulphonyl-2,1,3-benzoxadiazole (DBD-CO-Hz) as a precolumn fluorescence derivatization reagent for carboxylic acids in high-performance liquid chromatography.

Abstract

A new fluorescent reagent for carboxylic acids, 4-(N-hydrazinoformylmethyl-N-methyl)amino-7-N,N-dimethylaminosu lphonyl-2, 1,3-benzoxadiazole (DBD-CO-Hz) was synthesized and its applicability as a precolumn derivatization reagent in high-performance liquid chromatography (HPLC) was examined. DBD-CO-Hz reacted with saturated fatty acids in the presence of a condensing agent, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and pyridine at room temperature for 30 min to give fluorescent products. The reaction solution was subjected to a reversed-phase HPLC and detected fluorometrically at a wavelength of 550 nm with an excitation of 440 nm. The detection limits of the derivatives were at low fmol range on column.