Studies on Molecular Interaction of Rose Bengal with Surfactants

S. Sankari Devi and Asok Kumar Jana*
Department of Chemistry, Kanchi Mamunivar Centre for Post-Graduate Studies, Pondicherry – 605 008, India.

Abstract
The spectroscopic investigation on anionic dye, Rose Bengal with three different  types of surfactants such as CTAB(cationic), SLS(anionic)  and Triton X-100(TX-100), Tween-20, 40, 60, 80(nonionic) in aqueous media show that Rose Bengal forms a 1:1 molecular  complex with TX-100,Tweens and CTAB. No interaction is observed between Rose Bengal and SLS. The thermodynamic and spectrophotometric properties of these complexes suggest that Rose Bengal forms a strong charge transfer complex with TX-100 and Tweens whereas the interaction of Rose Bengal with CTAB is columbic in nature. Photogalvanic and photoconductometric studies also support the above interactions.
Keywords: Rose Bengal, CT interaction, CMC, Photoconductivity