SYNTHESIS OF 2,4-DIHYDROXYBENZALDEHYDE-ISONICOTINYLHYDRAZONE AND ITS FLUORESCENCE REACTION WITH ALUMINUM

A new fluorescent reagent, 2,4-dihydroxybenzaldehyde-isonicotinylhyraz one (DHBI), is synthesized and characterized by elemental analysis and infrared spectra (KBr disks). The fluorescent reaction of aluminium(I II) with the new reagent has been studied. The fluorescent excitation and emission wavelengths of the complex are at 394 and 484 nm, respect ively. The optimum pH range is 4.2-4.6; hence the pH is controlled in the optimum interval with a buffer solution (sodium formate-formic aci d) of pH 3.3. The linear range of the method is 0-6 mu g/25 ml. The mo lar ratio of aluminium to reagent is found to be 1:1. The proposed met hod has been used for the determination of trace aluminium in drinking water and edible bicarbonate of sodium with satisfactory results. (C) 1997 Academic Press.