Sensitive determination of total aliphatic amines in water samples by spectrofluorimetry using the new fluorogenic probe 3-(4-fluorobenzoyl)-2-quinolinecarboxaldehyde

Abstract

A rapid and highly sensitive fluorogenic method has been developed for the determination of total primary aliphatic amines with a novel fluorogenic derivatizing reagent, 3-(4-fluorobenzoyl)-2-quinolinecarboxaldehyde (FBQCA). FBQCA selectively reacts with amines to form a highly fluorescent isoindole in buffer of pH 9.7 and in the presence of potassium cyanide solution. The fluorescence intensity of derivatized products are detected at λex/λem = 480/546 nm. The results of the experiments showed a linear dynamic range of 1 × 10−8 to 6 × 10−6 mol L−1 with a detection limit (S/N = 3) of 6 nmol L−1. The method was successfully used for the direct spectrofluorimetric determination of aliphatic amines in water samples with recoveries of 95–104%.