QUENCHING FLUORESCENCE OF SAFRANINE-T BY INORGANIC-IONS IN AQUEOUS AND NONIONIC MICELLAR MEDIA

The fluorescence quenching of Safranine T by [Fe(CN)6]3-, [Fe(CN)6]4-, Fe2+, Co2+, Cu2+, Ni2+ and Mn2+ was studied in aqueous solutions as w ell as in solutions of non-ionic micelles of Triton X-100 and Tweens ( 20, 40, 60 and 80). The rate constants of quenching were calculated us ing the Stern-Volmer equation. In a micellar medium, the quenching eff iciency is less compared with that in an aqueous medium. It has been e stablished that the quenching phenomenon is not affected by the transf er of electrons from the quencher to the dye molecule, and that collis ional quenching plays the main role in this photochemical process.