Abstract: Anew highly sensitive and selective method has been developed for the spectrofluorometric determination of palladium( Ⅱ) with food colour Tartra-zine(TTZ) by heating them under a boiling water bath in a given time(20-60 min). It was found that the palladium (Ⅱ) might form a stable brown complex with TTZin HCl-NaAc buffer solution in the range of pH 2.6-4.0. The maximium excitation and emission wavelengths of complex are 528nm and 558nm. The composition of the complex is Pd( Ⅱ) :TTZ = 1:2. Its apparent stability constant(K) and molor absorptivity at the excitation wavelength(ε_ex) are 0.7× 10¹¹ and 1.45× 10⁴ L/mol.cm respectively. The quantum yield(Φ) is 0.011.By this method, Pd( Ⅱ ) can be determinated in the range of 0～12μg/25 mL. The limit of determination is 4 × 10^-3 μg/mL. The effect of deverse ions on the determination was also investigated. Asimple and rapid method was proposed for direct determination of Pd(Ⅱ ) in synthetic sample and in mineral without preseparation.

Key words: Palladium determination, Spectrofluorometry, Food colour, Tartrazine