Fluorescent derivatives flow injection analysis

Determination of aluminium in water for injection as a fluorescent complex Determination of stability of peptide drugs in solution Fluorescent derivatives and flow injection analysis... 

Flow injection analysis is discussed in more detail in Chapter 3. Some simple chemical reactions which result in the formation of fluorescent derivatives are shown in Table 7.2. All of these reactions could be adapted to enable analysis by FIA. 

The method of Fan and Dasgupta (1994) relics on tlie reaction of formaldehyde with 1,3-cyclohexane-dione in acidified ammonium acetate to form the fluorescent dihydropyridine derivative in a flow injection analysis system. Formaldehyde trapped in water can be reacted with pararosaniline and sodium sulfite under mild conditions (neutral pH, room temperature equilibration) to produce a colored product that is measured at 570 nm (Petreas et al. 1986). The presence of bisulfite is an interference in this reaction so the method cannot be used to sample atmospheres that contain sulfur dioxide. In addition, the method is reported to suffer from interferences resulting from the presence of other aldehydes and phenol (Hoogenboom et al. 1987). The indirect method of Hoogenboom et al. (1987) relies on the reaction of excess bisulfite in an aqueous solution of formaldehyde with 5,5 -dithiobis(2-nitrobenzoic acid) to form a colored product, the absorbance of which is measured at 412 nm. The method reported by Naruse et al. (1995) relies on the formation of a colored product obtained by reacting the aqueous formaldehyde with acetylacetone and ammonium acetate in acetic acid. Absorbance is measured at 414 nm. 

Y. Suzuki and T. Inoue, Determination of Cyanide Ion as Its Fluorescent Derivative by Flow Injection Analysis [in Japanese]. Bunseki Kagaku, 34 (1985) 53. 

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