Fluorescence growth and quenching effects in the magnesium-8-hydroxyquinoline-5-sulfonic acid-cationic surfactant system and their application to the determination of cetylpyridinium

摘要

The effect of ionic and micellar concentrations of cetyltrimethylammonium bromide (CTAB) and cetylpyridinium chloride (CPC) on the fluorescence characteristics of Al, Ga, In, La, Zn, and Mg chelates with 8-hydroxyquinoline-5-sulfonic acid were studied. It was found that in the presence of CTAB micelles, the fluorescence intensity of the chelates increases by a factor of 3.5-6. Addition of CPC to the M-R-CTAB system is accompanied by a partial decrease in the fluorescence intensity, which is most noticeable for the magnesium chelate. The character of the quenching was studied using the Stern-Volmer equation. A procedure for fluorimetric determination of CPC in the presence of up to 400-fold quantifies of CTAB was proposed.