A luminescence quenching study on the localization problem of tris(2,2'-bipyridyl)ruthenium(2+) in micelles and hemimicelles

Abstract

Quenching studies on the luminescence emission of Ru(bpy),*+ with ferrocyanide ion, 9-methylanthracene, and doxylstearic acids have been carried out in hemimicellar and micellar aggregates to gain insight into the location of this Raman and luminescence probe. Ru(bpy),*+ is bound to a more nonpolar hemimicellar hydrophobic region as evidenced from the observed larger Stokes shift in this case than in the case of a micellar environment. Stern-Volmer constants for the doxylstearic acid quenching of R~(bpy),~+ luminescence in micelles indicated that the optical electron in the MLCT state of the probe molecule resides in a bipyridyl ring which appears to be close to position 7 of the stearic acid chain.

Association of Nitrophenols to Sodium Dodecylsulfate Micelles

“…and 631 nm in SDS micelles. Luminescence lifetime meaSimilar spectral changes were already observed by others surements were obtained with a nitrogen laser (Laser Optics, authors in the study of the interaction of Ru(bpy) 2/ 3 with gated at 50 Hz and FWHM of 8 ns at 337 nm) as excitation SDS anionic micelles (7,9,10). It was also observed that source.…”

“…This spectral shift was interpreted to plex (9) or that the complex resides within the surfactant aggregates in the Stern layer (7,10). Therefore, from the above results in the presence of SDS micelles (6,7,9,10), the luminescence quenching of Ru(bpy) 2/ 3 can be used to monitor the incorporation of substrates (quenchers) into SDS micelles. In this case, the luminescent probe can be used to measure the quencher concentration in the micellar pseudophase.…”

“…spectrum of Ru(bpy) 2/ 3 observed in the presence of SDS micelles (7,9,10). This spectral shift was interpreted to plex (9) or that the complex resides within the surfactant aggregates in the Stern layer (7,10). Therefore, from the above results in the presence of SDS micelles (6,7,9,10), the luminescence quenching of Ru(bpy) 2/ 3 can be used to monitor the incorporation of substrates (quenchers) into SDS micelles.…”

“…eral phenolic compounds was observed in inverted and direct Another interesting aspect is the red shift of the emission micelles (2-4). spectrum of Ru(bpy) 2/ 3 observed in the presence of SDS micelles (7,9,10). This spectral shift was interpreted to plex (9) or that the complex resides within the surfactant aggregates in the Stern layer (7,10).…”

“…6 shows the plot of the reciprocal of the slopes according to Eq. [10]. The constants k / and k 0 can be calculated from the ordinate intercept and the slope in k q ( obs ) Å k / k q k 0 / k q .…”