Quenching of the triplet state of safranine-O by aliphatic amines in AOT reverse micelles studied by transient absorption spectroscopy

Autores
Porcal, Gabriela Valeria; Chesta, Carlos Alberto; Biasutti, Maria Alicia; Bertolotti, Sonia Graciela; Previtali, Carlos Mario
Año de publicación
2012
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
The photophysics of Safranine-O (3,6-diamino-2,7-dimethyl-5 phenyl phenazinium chloride) (SfH+Cl-) was investigated in reverse micelles (RMs) of AOT  (sodium bis(2-ethylhexyl) sulfosuccinate) with special emphasis on the triplet state processes. The excited singlet state properties were measured by absorption and fluorescence spectroscopy. Steady state anisotropy was also measured as a function of the water content. All the measurements indicate that the dye is localized in the interface, sensing a medium of polarity similar to EtOH:water (3:1) mixtures. The triplet is formed in its monoprotonated form, independently of the pH of the water used to prepare the RMs. The  maximum of the T-T absorption spectrum in RMs confirms this conclusion. The triplet lifetime is much longer in AOT RMs than in homogeneous organic solvents. The intersystem crossing quantum yields are similar to those in organic solvents. A remarkable difference is observed in the quenching by aliphatic amines, while the quenching by the hydrophobic tributylamine is similar to that in methanol, the hydro-soluble triethanolamine is one order of magnitude more effective in RMs than in homogeneous solution. In the latter case  the quenching process is interpreted by a very fast intramicellar quenching, the overall kinetics being controlled by the exchange of amine molecules between RMs. Semireduced dye is formed in the quenching process in RMs in the di-protonated state with a comparable quantum yield to the monoprotonated state formed in homogeneous solvents. The results point to the advantage of the reverse micellar system for the generation of active radicals for the initiation of vinyl polymerization, since a much lower concentration of amine can be employed with similar quantum yields.
Fil: Porcal, Gabriela Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina
Fil: Chesta, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina
Fil: Biasutti, Maria Alicia. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina
Fil: Bertolotti, Sonia Graciela. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina
Fil: Previtali, Carlos Mario. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina
Materia
TRIPLET STATE
REVERSE MICELLES
SAFRANINE-O
PHOTOPHYSICS
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/199023

id CONICETDig_5b0705372bfaf64e52bcd478fc0c02b7
oai_identifier_str oai:ri.conicet.gov.ar:11336/199023
network_acronym_str CONICETDig
repository_id_str 3498
network_name_str CONICET Digital (CONICET)
spelling Quenching of the triplet state of safranine-O by aliphatic amines in AOT reverse micelles studied by transient absorption spectroscopyPorcal, Gabriela ValeriaChesta, Carlos AlbertoBiasutti, Maria AliciaBertolotti, Sonia GracielaPrevitali, Carlos MarioTRIPLET STATEREVERSE MICELLESSAFRANINE-OPHOTOPHYSICShttps://purl.org/becyt/ford/1.4https://purl.org/becyt/ford/1The photophysics of Safranine-O (3,6-diamino-2,7-dimethyl-5 phenyl phenazinium chloride) (SfH+Cl-) was investigated in reverse micelles (RMs) of AOT  (sodium bis(2-ethylhexyl) sulfosuccinate) with special emphasis on the triplet state processes. The excited singlet state properties were measured by absorption and fluorescence spectroscopy. Steady state anisotropy was also measured as a function of the water content. All the measurements indicate that the dye is localized in the interface, sensing a medium of polarity similar to EtOH:water (3:1) mixtures. The triplet is formed in its monoprotonated form, independently of the pH of the water used to prepare the RMs. The  maximum of the T-T absorption spectrum in RMs confirms this conclusion. The triplet lifetime is much longer in AOT RMs than in homogeneous organic solvents. The intersystem crossing quantum yields are similar to those in organic solvents. A remarkable difference is observed in the quenching by aliphatic amines, while the quenching by the hydrophobic tributylamine is similar to that in methanol, the hydro-soluble triethanolamine is one order of magnitude more effective in RMs than in homogeneous solution. In the latter case  the quenching process is interpreted by a very fast intramicellar quenching, the overall kinetics being controlled by the exchange of amine molecules between RMs. Semireduced dye is formed in the quenching process in RMs in the di-protonated state with a comparable quantum yield to the monoprotonated state formed in homogeneous solvents. The results point to the advantage of the reverse micellar system for the generation of active radicals for the initiation of vinyl polymerization, since a much lower concentration of amine can be employed with similar quantum yields.Fil: Porcal, Gabriela Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; ArgentinaFil: Chesta, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; ArgentinaFil: Biasutti, Maria Alicia. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Bertolotti, Sonia Graciela. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Previtali, Carlos Mario. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaRoyal Society of Chemistry2012-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/199023Porcal, Gabriela Valeria; Chesta, Carlos Alberto; Biasutti, Maria Alicia; Bertolotti, Sonia Graciela; Previtali, Carlos Mario; Quenching of the triplet state of safranine-O by aliphatic amines in AOT reverse micelles studied by transient absorption spectroscopy; Royal Society of Chemistry; Photochemical and Photobiological Sciences; 11; 2; 1-2012; 302-3081474-905XCONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/url/https://pubs.rsc.org/en/content/articlelanding/2012/pp/c1pp05252ginfo:eu-repo/semantics/altIdentifier/doi/10.1039/C1PP05252Ginfo:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-03T10:01:10Zoai:ri.conicet.gov.ar:11336/199023instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-03 10:01:11.254CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Quenching of the triplet state of safranine-O by aliphatic amines in AOT reverse micelles studied by transient absorption spectroscopy
title Quenching of the triplet state of safranine-O by aliphatic amines in AOT reverse micelles studied by transient absorption spectroscopy
spellingShingle Quenching of the triplet state of safranine-O by aliphatic amines in AOT reverse micelles studied by transient absorption spectroscopy
Porcal, Gabriela Valeria
TRIPLET STATE
REVERSE MICELLES
SAFRANINE-O
PHOTOPHYSICS
title_short Quenching of the triplet state of safranine-O by aliphatic amines in AOT reverse micelles studied by transient absorption spectroscopy
title_full Quenching of the triplet state of safranine-O by aliphatic amines in AOT reverse micelles studied by transient absorption spectroscopy
title_fullStr Quenching of the triplet state of safranine-O by aliphatic amines in AOT reverse micelles studied by transient absorption spectroscopy
title_full_unstemmed Quenching of the triplet state of safranine-O by aliphatic amines in AOT reverse micelles studied by transient absorption spectroscopy
title_sort Quenching of the triplet state of safranine-O by aliphatic amines in AOT reverse micelles studied by transient absorption spectroscopy
dc.creator.none.fl_str_mv Porcal, Gabriela Valeria
Chesta, Carlos Alberto
Biasutti, Maria Alicia
Bertolotti, Sonia Graciela
Previtali, Carlos Mario
author Porcal, Gabriela Valeria
author_facet Porcal, Gabriela Valeria
Chesta, Carlos Alberto
Biasutti, Maria Alicia
Bertolotti, Sonia Graciela
Previtali, Carlos Mario
author_role author
author2 Chesta, Carlos Alberto
Biasutti, Maria Alicia
Bertolotti, Sonia Graciela
Previtali, Carlos Mario
author2_role author
author
author
author
dc.subject.none.fl_str_mv TRIPLET STATE
REVERSE MICELLES
SAFRANINE-O
PHOTOPHYSICS
topic TRIPLET STATE
REVERSE MICELLES
SAFRANINE-O
PHOTOPHYSICS
purl_subject.fl_str_mv https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
dc.description.none.fl_txt_mv The photophysics of Safranine-O (3,6-diamino-2,7-dimethyl-5 phenyl phenazinium chloride) (SfH+Cl-) was investigated in reverse micelles (RMs) of AOT  (sodium bis(2-ethylhexyl) sulfosuccinate) with special emphasis on the triplet state processes. The excited singlet state properties were measured by absorption and fluorescence spectroscopy. Steady state anisotropy was also measured as a function of the water content. All the measurements indicate that the dye is localized in the interface, sensing a medium of polarity similar to EtOH:water (3:1) mixtures. The triplet is formed in its monoprotonated form, independently of the pH of the water used to prepare the RMs. The  maximum of the T-T absorption spectrum in RMs confirms this conclusion. The triplet lifetime is much longer in AOT RMs than in homogeneous organic solvents. The intersystem crossing quantum yields are similar to those in organic solvents. A remarkable difference is observed in the quenching by aliphatic amines, while the quenching by the hydrophobic tributylamine is similar to that in methanol, the hydro-soluble triethanolamine is one order of magnitude more effective in RMs than in homogeneous solution. In the latter case  the quenching process is interpreted by a very fast intramicellar quenching, the overall kinetics being controlled by the exchange of amine molecules between RMs. Semireduced dye is formed in the quenching process in RMs in the di-protonated state with a comparable quantum yield to the monoprotonated state formed in homogeneous solvents. The results point to the advantage of the reverse micellar system for the generation of active radicals for the initiation of vinyl polymerization, since a much lower concentration of amine can be employed with similar quantum yields.
Fil: Porcal, Gabriela Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina
Fil: Chesta, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina
Fil: Biasutti, Maria Alicia. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina
Fil: Bertolotti, Sonia Graciela. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina
Fil: Previtali, Carlos Mario. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina
description The photophysics of Safranine-O (3,6-diamino-2,7-dimethyl-5 phenyl phenazinium chloride) (SfH+Cl-) was investigated in reverse micelles (RMs) of AOT  (sodium bis(2-ethylhexyl) sulfosuccinate) with special emphasis on the triplet state processes. The excited singlet state properties were measured by absorption and fluorescence spectroscopy. Steady state anisotropy was also measured as a function of the water content. All the measurements indicate that the dye is localized in the interface, sensing a medium of polarity similar to EtOH:water (3:1) mixtures. The triplet is formed in its monoprotonated form, independently of the pH of the water used to prepare the RMs. The  maximum of the T-T absorption spectrum in RMs confirms this conclusion. The triplet lifetime is much longer in AOT RMs than in homogeneous organic solvents. The intersystem crossing quantum yields are similar to those in organic solvents. A remarkable difference is observed in the quenching by aliphatic amines, while the quenching by the hydrophobic tributylamine is similar to that in methanol, the hydro-soluble triethanolamine is one order of magnitude more effective in RMs than in homogeneous solution. In the latter case  the quenching process is interpreted by a very fast intramicellar quenching, the overall kinetics being controlled by the exchange of amine molecules between RMs. Semireduced dye is formed in the quenching process in RMs in the di-protonated state with a comparable quantum yield to the monoprotonated state formed in homogeneous solvents. The results point to the advantage of the reverse micellar system for the generation of active radicals for the initiation of vinyl polymerization, since a much lower concentration of amine can be employed with similar quantum yields.
publishDate 2012
dc.date.none.fl_str_mv 2012-01
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://hdl.handle.net/11336/199023
Porcal, Gabriela Valeria; Chesta, Carlos Alberto; Biasutti, Maria Alicia; Bertolotti, Sonia Graciela; Previtali, Carlos Mario; Quenching of the triplet state of safranine-O by aliphatic amines in AOT reverse micelles studied by transient absorption spectroscopy; Royal Society of Chemistry; Photochemical and Photobiological Sciences; 11; 2; 1-2012; 302-308
1474-905X
CONICET Digital
CONICET
url http://hdl.handle.net/11336/199023
identifier_str_mv Porcal, Gabriela Valeria; Chesta, Carlos Alberto; Biasutti, Maria Alicia; Bertolotti, Sonia Graciela; Previtali, Carlos Mario; Quenching of the triplet state of safranine-O by aliphatic amines in AOT reverse micelles studied by transient absorption spectroscopy; Royal Society of Chemistry; Photochemical and Photobiological Sciences; 11; 2; 1-2012; 302-308
1474-905X
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/url/https://pubs.rsc.org/en/content/articlelanding/2012/pp/c1pp05252g
info:eu-repo/semantics/altIdentifier/doi/10.1039/C1PP05252G
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
eu_rights_str_mv openAccess
rights_invalid_str_mv https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
dc.format.none.fl_str_mv application/pdf
application/pdf
application/pdf
application/pdf
application/pdf
dc.publisher.none.fl_str_mv Royal Society of Chemistry
publisher.none.fl_str_mv Royal Society of Chemistry
dc.source.none.fl_str_mv reponame:CONICET Digital (CONICET)
instname:Consejo Nacional de Investigaciones Científicas y Técnicas
reponame_str CONICET Digital (CONICET)
collection CONICET Digital (CONICET)
instname_str Consejo Nacional de Investigaciones Científicas y Técnicas
repository.name.fl_str_mv CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas
repository.mail.fl_str_mv dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar
_version_ 1842269681509990400
score 13.13397