Rose Bengal adsorbed on microgranular cellulose: Evidence on fluorescent dimers
Rose Bengal adsorbed on microgranular cellulose was studied in the solid phase by total and diffuse reflectance and steady-state emission spectroscopy. A simple monomer-dimer equilibrium fitted reflectance data up to dye loadings of 4 × 10-7 mol (g cellulose)-1 and allowed calculation of monomer and...
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todo:paper_1474905X_v3_n7_p674_Rodriguez2023-10-03T16:18:27Z Rose Bengal adsorbed on microgranular cellulose: Evidence on fluorescent dimers Rodríguez, H.B. Lagorio, M.G. San Román, E. alcohol cellulose dimer monomer rose bengal acid base balance adsorption kinetics article controlled study diffuse reflectance spectroscopy dimerization drug adsorption drug determination energy transfer flame photometry fluorescence spectroscopy luminescence mathematical model observation photochemistry photosensitization physical chemistry priority journal quantum chemistry quantum yield solid state steady state surface charge Roman Rose Bengal adsorbed on microgranular cellulose was studied in the solid phase by total and diffuse reflectance and steady-state emission spectroscopy. A simple monomer-dimer equilibrium fitted reflectance data up to dye loadings of 4 × 10-7 mol (g cellulose)-1 and allowed calculation of monomer and dimer spectra. Further increase of dye loading resulted in the formation of higher aggregates. Observed emission and excitation spectra and quantum yields were corrected for reabsorption and reemission of luminescence, using a previously developed model, within the assumption that only monomers are luminescent [M. G. Lagorio, L. E. Dicelio, M. I. Litter and E. San Román, J. Chem. Soc, Faraday Trans., 1998, 94, 419]. An apparent increase of fluorescence quantum yield with dye loading was found, which was attributed to the occurrence of dimer fluorescence. Extension of the model to two luminescent species (i.e. monomer and dimer) yielded constant fluorescence quantum yields for the monomer, ΦM = 0.120 ± 0.004, and for the dimer, ΦD = 0.070 ± 0.006. The monomer quantum yield is close to the value found for the same dye in basic ethanol. The presence of fluorescent dimers and calculated quantum yields are supported by analysis of the excitation spectra and other experimental evidence. The possible occurrence of non-radiative energy transfer and the effect of surface charge on the properties of the dimer are analyzed. © The Royal Society of Chemistry and Owner Societies 2004. Fil:Rodríguez, H.B. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Lagorio, M.G. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:San Román, E. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_1474905X_v3_n7_p674_Rodriguez |
institution |
Universidad de Buenos Aires |
institution_str |
I-28 |
repository_str |
R-134 |
collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
topic |
alcohol cellulose dimer monomer rose bengal acid base balance adsorption kinetics article controlled study diffuse reflectance spectroscopy dimerization drug adsorption drug determination energy transfer flame photometry fluorescence spectroscopy luminescence mathematical model observation photochemistry photosensitization physical chemistry priority journal quantum chemistry quantum yield solid state steady state surface charge Roman |
spellingShingle |
alcohol cellulose dimer monomer rose bengal acid base balance adsorption kinetics article controlled study diffuse reflectance spectroscopy dimerization drug adsorption drug determination energy transfer flame photometry fluorescence spectroscopy luminescence mathematical model observation photochemistry photosensitization physical chemistry priority journal quantum chemistry quantum yield solid state steady state surface charge Roman Rodríguez, H.B. Lagorio, M.G. San Román, E. Rose Bengal adsorbed on microgranular cellulose: Evidence on fluorescent dimers |
topic_facet |
alcohol cellulose dimer monomer rose bengal acid base balance adsorption kinetics article controlled study diffuse reflectance spectroscopy dimerization drug adsorption drug determination energy transfer flame photometry fluorescence spectroscopy luminescence mathematical model observation photochemistry photosensitization physical chemistry priority journal quantum chemistry quantum yield solid state steady state surface charge Roman |
description |
Rose Bengal adsorbed on microgranular cellulose was studied in the solid phase by total and diffuse reflectance and steady-state emission spectroscopy. A simple monomer-dimer equilibrium fitted reflectance data up to dye loadings of 4 × 10-7 mol (g cellulose)-1 and allowed calculation of monomer and dimer spectra. Further increase of dye loading resulted in the formation of higher aggregates. Observed emission and excitation spectra and quantum yields were corrected for reabsorption and reemission of luminescence, using a previously developed model, within the assumption that only monomers are luminescent [M. G. Lagorio, L. E. Dicelio, M. I. Litter and E. San Román, J. Chem. Soc, Faraday Trans., 1998, 94, 419]. An apparent increase of fluorescence quantum yield with dye loading was found, which was attributed to the occurrence of dimer fluorescence. Extension of the model to two luminescent species (i.e. monomer and dimer) yielded constant fluorescence quantum yields for the monomer, ΦM = 0.120 ± 0.004, and for the dimer, ΦD = 0.070 ± 0.006. The monomer quantum yield is close to the value found for the same dye in basic ethanol. The presence of fluorescent dimers and calculated quantum yields are supported by analysis of the excitation spectra and other experimental evidence. The possible occurrence of non-radiative energy transfer and the effect of surface charge on the properties of the dimer are analyzed. © The Royal Society of Chemistry and Owner Societies 2004. |
format |
JOUR |
author |
Rodríguez, H.B. Lagorio, M.G. San Román, E. |
author_facet |
Rodríguez, H.B. Lagorio, M.G. San Román, E. |
author_sort |
Rodríguez, H.B. |
title |
Rose Bengal adsorbed on microgranular cellulose: Evidence on fluorescent dimers |
title_short |
Rose Bengal adsorbed on microgranular cellulose: Evidence on fluorescent dimers |
title_full |
Rose Bengal adsorbed on microgranular cellulose: Evidence on fluorescent dimers |
title_fullStr |
Rose Bengal adsorbed on microgranular cellulose: Evidence on fluorescent dimers |
title_full_unstemmed |
Rose Bengal adsorbed on microgranular cellulose: Evidence on fluorescent dimers |
title_sort |
rose bengal adsorbed on microgranular cellulose: evidence on fluorescent dimers |
url |
http://hdl.handle.net/20.500.12110/paper_1474905X_v3_n7_p674_Rodriguez |
work_keys_str_mv |
AT rodriguezhb rosebengaladsorbedonmicrogranularcelluloseevidenceonfluorescentdimers AT lagoriomg rosebengaladsorbedonmicrogranularcelluloseevidenceonfluorescentdimers AT sanromane rosebengaladsorbedonmicrogranularcelluloseevidenceonfluorescentdimers |
_version_ |
1807321752261361664 |