Determination of traces of gallium in the presence of aluminium by synchronous derivative spectrofluorimetry

Gallium (2–100 ng ml^?1) is determined in the presence of ?500-fold amounts (by weight) of aluminium by using synchronous first- or second-derivative spectrofluorimetry. The fluorescence of the gallium chelate with 1-(2-pyridylazo)-2-naphthol is greatly enhanced compared to that of the aluminium chelate in micellar sodium dodecyl sulphate solutions. The limit of detection is about 0.6 ng ml^?1.