A new fluorescent probe for sensitive detection of carbonyl compounds

A new method for the convenient and sensitive detection of aldehydes and ke tones in environmental samples was developed. This method is described in d etail for the measurement of carbonyls in water samples, but it is also pot entially applicable to their determination in air. Derivatization of carbon yls is performed using N-(5-dimethylamino-1-naphtalenesulphonamido)-3-oxape ntane-1,5-dioxyamine (dansyloxyamine, DNSOA). The resulting oxime ethers ar e separated by using reversed phase liquid chromatography and fluorescence detection. Parameters influencing both reactivity and sensitivity are discu ssed. The oxyamino function allows efficient chemical derivatization in wat er without the use of a catalyst. The dansyl fluorophore and the reactive o xyamino group are linked by an etheral chain which leads to very similar fl uorescence responses for formaldehyde, acetaldehyde and acetone derivatives . The detection Limit of this method compares favourably with classical met hods. Furthermore, the analysis procedure is easily set up and can be direc tly applied to environmental water samples. (C) 1999 Elsevier Science B.V. All rights reserved.