1H,5H,11H-[1]BENZOPYRANO[6,7,8-IJ]QUINOLIZINE-9-ACETIC ACID 2,3,6,7-TETRAHYDRO-11-OXOHYDRAZIDE FLUOROGENIC REAGENT FOR LIQUID-CHROMATOGRAPHIC DETERMINATION OF ALDEHYDES AND KETONES

Carbonyls are widely occurring environmental compounds. Various aldehydes and ketones are major constituents of food aromas, and a large number of pharmaceuticals and biological compounds contain carbonyl groups. Therefore, the determination of traces of carbonyls is of major importance. Methods for the determination of carbonyl compounds by means of liquid chromatography have been improved by the use of fluorescent derivatizing reagents. This paper describes the use of a highly reactive reagent with a 7-aminocoumarin moiety as the fluorophore and carboxylic hydrazide as the group reacting with the carbonyl function. Aliphatic, unsaturated and aromatic carbonyls, dicarbonyls and other difunctional carbonyls react with this reagent and chromatographic separation in both normal- and reversed-phase systems with fluorescence detection can be easily performed. The labelling reaction and the structure of the derivatives are discussed, together with the properties of these derivatives in both normal- and reversed-phase chromatographic systems. UV absorbance, corrected fluorescence spectra data and quantum yields from luminarin 3 and representative luminarin 3 derivatives of carbonyl compounds are presented. The results show that luminarin 3 derivatives of carbonyl compounds give high fluorescence quantum yields (phi(f) almost-equal-to 0.71) and good intrinsic fluorescence sensitivities (IFS almost-equal-to 5.68). Fluorimetric detection limits for most compounds range between 60 and 1950 fmol injected. The method is suitable for quantitative analysis, with a reproducibility of about 1.8% (relative standard deviation) for 100 pmol injected.