Abstract: | ABSTRACT A detailed study and evaluation of the presence of Cr(III), Zn(II) and Pb(II) and various parameters affecting the intensity of the chemiluminescent reaction of TCPO and 2-NPO with hydrogen peroxide in the presence of 3-aminofluoranthene, as the fluorophore, and imidazole (IMI) as catalyst, is presented. Depending on the unprotonated imidazole and fluorophore concentrations, these metal ions enhance the intensity of the fluorophore at pH's higher than 8.0. At pH = 7.0, in the presence of IMI/HIMI+ (IMI = 1×10?2 mol.L?1), tris(hydroxymethyl)aminomethane or HPO4 2?/H2PO4 ? buffers, no effect of these metal ions was observed. A critical comparison with the data reported in the literature is presented. |