FLUOROMETRIC-DETERMINATION TRACES OF ALUMINUM IN SOIL EXTRACTS

Salicylaldehyde picolinoylhydrazone (SAPH) form a fluorescent complex with aluminium (lambda(ex) = 384 nm, lambda(em) = 468 nm) in acidic me dium (stoichiometry 1:3, Al:SAPH). Two procedures based on the direct or standard additions methods has been proposed for the determination of concentrations down to 1-2 mug/dm3 of Al(III). The effects of 72 io ns in the method has been evaluated and different masking agent reacti ons have been tested. The method has been used satisfactorily for the determination of aluminium at a level of mug/dm3 in acetate extracts o f several agricultural soils. The method has been compared favourably with ICP spectroscopy emission.