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Noboru Kitamura - One of the best experts on this subject based on the ideXlab platform.
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Time-Resolved Total Internal Reflection Fluorometry Study on Chemical and Structural Characteristics at Water/Oil Interfaces
Bulletin of the Chemical Society of Japan, 2001Co-Authors: Shoji Ishizaka, Noboru KitamuraAbstract:Structures and characteristics of water/oil interfaces at the molecular level are reviewed. Dynamic fluorescence anisotropy of Sulforhodamine 101 (SR101) and excitation energy transfer from SR101 to Acid Blue 1 (AB1) at water/oil interfaces were studied by using time-resolved total internal reflection (TIR) fluorometry. The results indicated that a water/carbon tetrachloride (CCl4) interface was sharp with respect to the molecular size of SR101 (∼10 A), while a water/1,2-dichloroethane (DCE) interface was relatively rough compared to the water/CCl4 interface. The present results were also compared with those predicted from molecular dynamic simulations and the thermally capillary wave theory. Furthermore, on the basis of fluorescence dynamic measurements of Sulforhodamine B (SRB) adsorbed at a water/oil interface, a relationship between thickness/roughness and the polarity at the interface was discussed.
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excitation energy transfer from Sulforhodamine 101 to acid blue 1 at a liquid liquid interface experimental approach to estimate interfacial roughness
Analytical Chemistry, 1999Co-Authors: Shoji Ishizaka, Satoshi Habuchi, And Haeng-boo Kim, Noboru KitamuraAbstract:Dynamic fluorescence anisotropy of Sulforhodamine 101 (SR101) and excitation energy transfer from SR101 to Acid Blue 1 (AB1) at water/carbon tetrachloride (CCl4) and water/1,2-dichloroethane (DCE) interfaces were studied by using time-resolved total-internal-reflection (TIR) fluorometry. A magic-angle dependence of the TIR fluorescence dynamic anisotropy revealed that rotational reorientation of SR101 at the water/CCl4 interface was restricted in the two-dimensional plane of the interface, while that at the water/DCE interface took place rather freely, similar to reorientation in an isotropic medium. Furthermore, the structural dimension derived from the excitation energy transfer dynamics measurements at the water/CCl4 or water/DCE interface was 1.93 or 2.48, respectively. These results indicated that the water/CCl4 interface was sharp with respect to the molecular size of SR101 (∼10 A), while the water/DCE interface was relatively rough compared to the water/CCl4 interface. Structural dimension analysis...
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Total Internal Reflection Fluorescence Dynamic Anisotropy of Sulforhodamine 101 at a Liquid/Liquid Interface: Rotational Reorientation Times and Interfacial Structures
Analytical Chemistry, 1999Co-Authors: Shoji Ishizaka, Kiyoharu Nakatani, Satoshi Habuchi, Noboru KitamuraAbstract:The dynamic anisotropy of Sulforhodamine 101 (SR101) at water/phthalate ester (PE, bis(2-ethylhexyl) phthalate, di-n-heptyl phthalate, di-n-butyl phthalate, or di-n-ethyl phthalate) interfaces was studied by using time-resolved total internal reflection (TIR) fluorometry. A magic-angle dependence of the TIR fluorescence dynamics revealed that rotational reorientation of SR101 at the water/PE interface was restricted in the X−Y plane (in-plane) of the interface. The results indicated that the interface was sharp with respect to the molecular size of SR101 (∼10 A). In-plane rotational reorientation of SR101 at the interface showed two time constants (τrot). The fast component (τ1rot) was similar to that in water irrespective of the nature of PE, while the slow one (τ2rot) was affected by the viscosity of PE but not directly by the macroscopic viscosity. The two rotational reorientation times of SR101 characteristic to the water/PE interface were explained in terms of different adsorption modes of the dye on...
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total internal reflection fluorescence dynamic anisotropy of Sulforhodamine 101 at a liquid liquid interface rotational reorientation times and interfacial structures
Analytical Chemistry, 1999Co-Authors: Shoji Ishizaka, Kiyoharu Nakatani, Satoshi Habuchi, Noboru KitamuraAbstract:The dynamic anisotropy of Sulforhodamine 101 (SR101) at water/phthalate ester (PE, bis(2-ethylhexyl) phthalate, di-n-heptyl phthalate, di-n-butyl phthalate, or di-n-ethyl phthalate) interfaces was studied by using time-resolved total internal reflection (TIR) fluorometry. A magic-angle dependence of the TIR fluorescence dynamics revealed that rotational reorientation of SR101 at the water/PE interface was restricted in the X−Y plane (in-plane) of the interface. The results indicated that the interface was sharp with respect to the molecular size of SR101 (∼10 A). In-plane rotational reorientation of SR101 at the interface showed two time constants (τrot). The fast component (τ1rot) was similar to that in water irrespective of the nature of PE, while the slow one (τ2rot) was affected by the viscosity of PE but not directly by the macroscopic viscosity. The two rotational reorientation times of SR101 characteristic to the water/PE interface were explained in terms of different adsorption modes of the dye on...
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Excitation Energy Transfer from Sulforhodamine 101 to Acid Blue 1 at a Liquid/Liquid Interface: Experimental Approach To Estimate Interfacial Roughness
Analytical Chemistry, 1999Co-Authors: Shoji Ishizaka, Satoshi Habuchi, And Haeng-boo Kim, Noboru KitamuraAbstract:Dynamic fluorescence anisotropy of Sulforhodamine 101 (SR101) and excitation energy transfer from SR101 to Acid Blue 1 (AB1) at water/carbon tetrachloride (CCl4) and water/1,2-dichloroethane (DCE) interfaces were studied by using time-resolved total-internal-reflection (TIR) fluorometry. A magic-angle dependence of the TIR fluorescence dynamic anisotropy revealed that rotational reorientation of SR101 at the water/CCl4 interface was restricted in the two-dimensional plane of the interface, while that at the water/DCE interface took place rather freely, similar to reorientation in an isotropic medium. Furthermore, the structural dimension derived from the excitation energy transfer dynamics measurements at the water/CCl4 or water/DCE interface was 1.93 or 2.48, respectively. These results indicated that the water/CCl4 interface was sharp with respect to the molecular size of SR101 (∼10 A), while the water/DCE interface was relatively rough compared to the water/CCl4 interface. Structural dimension analysis...
Kiyoharu Nakatani - One of the best experts on this subject based on the ideXlab platform.
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Interfacial behavior of Sulforhodamine 101 at the polarized water/1,2-dichloroethane interface studied by spectroelectrochemical techniques.
Analytical and bioanalytical chemistry, 2006Co-Authors: Hirohisa Nagatani, Shingo Suzuki, David J. Fermín, Hubert H. Girault, Kiyoharu NakataniAbstract:The transfer mechanism of an amphoteric rhodamine, Sulforhodamine 101 (SR101), across the polarized water/1,2-dichloroethane (DCE) interface was investigated using cyclic voltammetry, differential voltfluorometry and potential-modulated fluorescence (PMF) spectroscopy. The voltammetric response for the ion transfer of SR101 monoanion from water to DCE was observed as the diffusion-controlled transfer process. An unusual voltammetric response was found at 0.15 V more negative than the formal transfer potential of SR101− ΔWO φ 0 in the cyclic voltammogram and voltfluorogram. The frequency dependence of the PMF responses confirmed the presence of the adsorption processes at negative potentials. In addition, a further transient adsorption step was uncovered at ΔWO φ 0: The interfacial mechanism of SR101 is discussed by comparing the results obtained from each technique.
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interfacial behavior of Sulforhodamine 101 at the polarized water 1 2 dichloroethane interface studied by spectroelectrochemical techniques
Analytical and Bioanalytical Chemistry, 2006Co-Authors: Hirohisa Nagatani, Shingo Suzuki, David J. Fermín, Hubert H. Girault, Kiyoharu NakataniAbstract:The transfer mechanism of an amphoteric rhodamine, Sulforhodamine 101 (SR101), across the polarized water/1,2-dichloroethane (DCE) interface was investigated using cyclic voltammetry, differential voltfluorometry and potential-modulated fluorescence (PMF) spectroscopy. The voltammetric response for the ion transfer of SR101 monoanion from water to DCE was observed as the diffusion-controlled transfer process. An unusual voltammetric response was found at 0.15 V more negative than the formal transfer potential of SR101− ΔWO φ 0 in the cyclic voltammogram and voltfluorogram. The frequency dependence of the PMF responses confirmed the presence of the adsorption processes at negative potentials. In addition, a further transient adsorption step was uncovered at ΔWO φ 0: The interfacial mechanism of SR101 is discussed by comparing the results obtained from each technique.
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Total Internal Reflection Fluorescence Dynamic Anisotropy of Sulforhodamine 101 at a Liquid/Liquid Interface: Rotational Reorientation Times and Interfacial Structures
Analytical Chemistry, 1999Co-Authors: Shoji Ishizaka, Kiyoharu Nakatani, Satoshi Habuchi, Noboru KitamuraAbstract:The dynamic anisotropy of Sulforhodamine 101 (SR101) at water/phthalate ester (PE, bis(2-ethylhexyl) phthalate, di-n-heptyl phthalate, di-n-butyl phthalate, or di-n-ethyl phthalate) interfaces was studied by using time-resolved total internal reflection (TIR) fluorometry. A magic-angle dependence of the TIR fluorescence dynamics revealed that rotational reorientation of SR101 at the water/PE interface was restricted in the X−Y plane (in-plane) of the interface. The results indicated that the interface was sharp with respect to the molecular size of SR101 (∼10 A). In-plane rotational reorientation of SR101 at the interface showed two time constants (τrot). The fast component (τ1rot) was similar to that in water irrespective of the nature of PE, while the slow one (τ2rot) was affected by the viscosity of PE but not directly by the macroscopic viscosity. The two rotational reorientation times of SR101 characteristic to the water/PE interface were explained in terms of different adsorption modes of the dye on...
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total internal reflection fluorescence dynamic anisotropy of Sulforhodamine 101 at a liquid liquid interface rotational reorientation times and interfacial structures
Analytical Chemistry, 1999Co-Authors: Shoji Ishizaka, Kiyoharu Nakatani, Satoshi Habuchi, Noboru KitamuraAbstract:The dynamic anisotropy of Sulforhodamine 101 (SR101) at water/phthalate ester (PE, bis(2-ethylhexyl) phthalate, di-n-heptyl phthalate, di-n-butyl phthalate, or di-n-ethyl phthalate) interfaces was studied by using time-resolved total internal reflection (TIR) fluorometry. A magic-angle dependence of the TIR fluorescence dynamics revealed that rotational reorientation of SR101 at the water/PE interface was restricted in the X−Y plane (in-plane) of the interface. The results indicated that the interface was sharp with respect to the molecular size of SR101 (∼10 A). In-plane rotational reorientation of SR101 at the interface showed two time constants (τrot). The fast component (τ1rot) was similar to that in water irrespective of the nature of PE, while the slow one (τ2rot) was affected by the viscosity of PE but not directly by the macroscopic viscosity. The two rotational reorientation times of SR101 characteristic to the water/PE interface were explained in terms of different adsorption modes of the dye on...
Shoji Ishizaka - One of the best experts on this subject based on the ideXlab platform.
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Time-Resolved Total Internal Reflection Fluorometry Study on Chemical and Structural Characteristics at Water/Oil Interfaces
Bulletin of the Chemical Society of Japan, 2001Co-Authors: Shoji Ishizaka, Noboru KitamuraAbstract:Structures and characteristics of water/oil interfaces at the molecular level are reviewed. Dynamic fluorescence anisotropy of Sulforhodamine 101 (SR101) and excitation energy transfer from SR101 to Acid Blue 1 (AB1) at water/oil interfaces were studied by using time-resolved total internal reflection (TIR) fluorometry. The results indicated that a water/carbon tetrachloride (CCl4) interface was sharp with respect to the molecular size of SR101 (∼10 A), while a water/1,2-dichloroethane (DCE) interface was relatively rough compared to the water/CCl4 interface. The present results were also compared with those predicted from molecular dynamic simulations and the thermally capillary wave theory. Furthermore, on the basis of fluorescence dynamic measurements of Sulforhodamine B (SRB) adsorbed at a water/oil interface, a relationship between thickness/roughness and the polarity at the interface was discussed.
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excitation energy transfer from Sulforhodamine 101 to acid blue 1 at a liquid liquid interface experimental approach to estimate interfacial roughness
Analytical Chemistry, 1999Co-Authors: Shoji Ishizaka, Satoshi Habuchi, And Haeng-boo Kim, Noboru KitamuraAbstract:Dynamic fluorescence anisotropy of Sulforhodamine 101 (SR101) and excitation energy transfer from SR101 to Acid Blue 1 (AB1) at water/carbon tetrachloride (CCl4) and water/1,2-dichloroethane (DCE) interfaces were studied by using time-resolved total-internal-reflection (TIR) fluorometry. A magic-angle dependence of the TIR fluorescence dynamic anisotropy revealed that rotational reorientation of SR101 at the water/CCl4 interface was restricted in the two-dimensional plane of the interface, while that at the water/DCE interface took place rather freely, similar to reorientation in an isotropic medium. Furthermore, the structural dimension derived from the excitation energy transfer dynamics measurements at the water/CCl4 or water/DCE interface was 1.93 or 2.48, respectively. These results indicated that the water/CCl4 interface was sharp with respect to the molecular size of SR101 (∼10 A), while the water/DCE interface was relatively rough compared to the water/CCl4 interface. Structural dimension analysis...
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Total Internal Reflection Fluorescence Dynamic Anisotropy of Sulforhodamine 101 at a Liquid/Liquid Interface: Rotational Reorientation Times and Interfacial Structures
Analytical Chemistry, 1999Co-Authors: Shoji Ishizaka, Kiyoharu Nakatani, Satoshi Habuchi, Noboru KitamuraAbstract:The dynamic anisotropy of Sulforhodamine 101 (SR101) at water/phthalate ester (PE, bis(2-ethylhexyl) phthalate, di-n-heptyl phthalate, di-n-butyl phthalate, or di-n-ethyl phthalate) interfaces was studied by using time-resolved total internal reflection (TIR) fluorometry. A magic-angle dependence of the TIR fluorescence dynamics revealed that rotational reorientation of SR101 at the water/PE interface was restricted in the X−Y plane (in-plane) of the interface. The results indicated that the interface was sharp with respect to the molecular size of SR101 (∼10 A). In-plane rotational reorientation of SR101 at the interface showed two time constants (τrot). The fast component (τ1rot) was similar to that in water irrespective of the nature of PE, while the slow one (τ2rot) was affected by the viscosity of PE but not directly by the macroscopic viscosity. The two rotational reorientation times of SR101 characteristic to the water/PE interface were explained in terms of different adsorption modes of the dye on...
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total internal reflection fluorescence dynamic anisotropy of Sulforhodamine 101 at a liquid liquid interface rotational reorientation times and interfacial structures
Analytical Chemistry, 1999Co-Authors: Shoji Ishizaka, Kiyoharu Nakatani, Satoshi Habuchi, Noboru KitamuraAbstract:The dynamic anisotropy of Sulforhodamine 101 (SR101) at water/phthalate ester (PE, bis(2-ethylhexyl) phthalate, di-n-heptyl phthalate, di-n-butyl phthalate, or di-n-ethyl phthalate) interfaces was studied by using time-resolved total internal reflection (TIR) fluorometry. A magic-angle dependence of the TIR fluorescence dynamics revealed that rotational reorientation of SR101 at the water/PE interface was restricted in the X−Y plane (in-plane) of the interface. The results indicated that the interface was sharp with respect to the molecular size of SR101 (∼10 A). In-plane rotational reorientation of SR101 at the interface showed two time constants (τrot). The fast component (τ1rot) was similar to that in water irrespective of the nature of PE, while the slow one (τ2rot) was affected by the viscosity of PE but not directly by the macroscopic viscosity. The two rotational reorientation times of SR101 characteristic to the water/PE interface were explained in terms of different adsorption modes of the dye on...
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Excitation Energy Transfer from Sulforhodamine 101 to Acid Blue 1 at a Liquid/Liquid Interface: Experimental Approach To Estimate Interfacial Roughness
Analytical Chemistry, 1999Co-Authors: Shoji Ishizaka, Satoshi Habuchi, And Haeng-boo Kim, Noboru KitamuraAbstract:Dynamic fluorescence anisotropy of Sulforhodamine 101 (SR101) and excitation energy transfer from SR101 to Acid Blue 1 (AB1) at water/carbon tetrachloride (CCl4) and water/1,2-dichloroethane (DCE) interfaces were studied by using time-resolved total-internal-reflection (TIR) fluorometry. A magic-angle dependence of the TIR fluorescence dynamic anisotropy revealed that rotational reorientation of SR101 at the water/CCl4 interface was restricted in the two-dimensional plane of the interface, while that at the water/DCE interface took place rather freely, similar to reorientation in an isotropic medium. Furthermore, the structural dimension derived from the excitation energy transfer dynamics measurements at the water/CCl4 or water/DCE interface was 1.93 or 2.48, respectively. These results indicated that the water/CCl4 interface was sharp with respect to the molecular size of SR101 (∼10 A), while the water/DCE interface was relatively rough compared to the water/CCl4 interface. Structural dimension analysis...
Swen Hülsmann - One of the best experts on this subject based on the ideXlab platform.
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Limitations of Sulforhodamine 101 for Brain Imaging.
Frontiers in cellular neuroscience, 2017Co-Authors: Swen Hülsmann, Liya Hagos, Heike Heuer, Christian SchnellAbstract:Since 2004 the red fluorescent dye Sulforhodamine 101 (SR101) has been boosting the functional analysis of astrocytes in a functional environment in an unprecedented way. However, two major calamities have been challenging the usefulness of this tool for cellular imaging: (i) SR101 is not as specific for astrocytes as previously reported and (ii) discoveries of severe excitatory side effects of SR101 bear the risk of unwanted alteration of the system of interest. In this article, we summarize the current knowledge about this dye and try to shine light on the physiological and pathological implications that arise from the analyses of SR101 stained brain slices.
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Unspecific labelling of oligodendrocytes by Sulforhodamine 101 depends on astrocytic uptake via the thyroid hormone transporter OATP1C1 (SLCO1C1).
Neuroscience letters, 2016Co-Authors: Liya Hagos, Swen HülsmannAbstract:Abstracts The red fluorescent dye Sulforhodamine 101 (SR101) is often used as a marker for astrocytes, although variations of the staining protocol have been shown to influence the preferentially labeled cell type. Here we analyzed SR101-labeling of oligodendrocytes in the hippocampal slices preparation of PLP-EGFP mice. Using different staining protocols, we found robust SR101-labeled oligodendrocytes in the CA1 stratum radiatum of the hippocampus. Application of L-thyroxin, which is known to block SR101 transport into astrocytes via competitive inhibition of the multi-specific OATP1C1 (SLCO1C1) transporter, significantly reduced oligodendrocyte labeling. Since OATP1C1 is not expressed in oligodendrocytes, we conclude that oligodendrocyte labeling with SR101 requires SR101-uptake by astrocytes, which then diffuses to oligodendrocytes via heterotypic gap junctions of the pan-glial network. In summary, unequivocal identification of a particular cell type is not possible by SR101 only, hence caution is recommended when using SR101 in future studies.
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The multispecific thyroid hormone transporter OATP1C1 mediates cell-specific Sulforhodamine 101-labeling of hippocampal astrocytes
Brain structure & function, 2013Co-Authors: Christian Schnell, Heike Heuer, Yohannes Hagos, Ali Shahmoradi, Sven P. Wichert, Steffen Mayerl, Moritz J. Rossner, Swen HülsmannAbstract:Sulforhodamine 101 (SR101) is widely used for astrocyte identification, though the labeling mechanism remains unknown and the efficacy of labeling in different brain regions is heterogeneous. By combining region-specific isolation of astrocytes followed by transcriptome analysis, two-photon excitation microscopy, and mouse genetics, we identified the thyroid hormone transporter OATP1C1 as the SR101-uptake transporter in hippocampus and cortex.
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Active Sulforhodamine 101 Uptake into Hippocampal Astrocytes
PloS one, 2012Co-Authors: Christian Schnell, Yohannes Hagos, Swen HülsmannAbstract:Sulforhodamine 101 (SR101) is widely used as a marker of astrocytes. In this study we investigated labeling of astrocytes by SR101 in acute slices from the ventrolateral medulla and the hippocampus of transgenic mice expressing EGFP under the control of the astrocyte-specific human GFAP promoter. While SR101 efficiently and specifically labeled EGFP-expressing astrocytes in hippocampus, we found that the same staining procedure failed to label astrocytes efficiently in the ventrolateral medulla. Although carbenoxolone is able to decrease the SR101-labeling of astrocytes in the hippocampus, it is unlikely that SR101 is taken up via gap-junction hemichannels because mefloquine, a blocker for pannexin and connexin hemichannels, was unable to prevent SR101-labeling of hippocampal astrocytes. However, SR101-labeling of the hippocampal astrocytes was significantly reduced by substrates of organic anion transport polypeptides, including estron-3-sulfate and dehydroepiandrosterone sulfate, suggesting that SR101 is actively transported into hippocampal astrocytes.
Thierry Gacoin - One of the best experts on this subject based on the ideXlab platform.
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Optical properties of dye molecules as a function of the surrounding dielectric medium
Physical Review A, 1999Co-Authors: G. Lamouche, P. Lavallard, Thierry GacoinAbstract:~Received 15 October 1998! We perform an optical study of Sulforhodamine B and Sulforhodamine 101 molecules solved in water droplets ~reversed micelles! that are stabilized by a surfactant and suspended in various mixtures of heptane and toluene. While the dielectric permittivity of the surrounding medium varies with the proportions of heptane and toluene, the chemical environment of the dye molecules always remains the same. The modifications of the optical properties of the dye molecules can then be solely attributed to the effect of surrounding dielectric medium on the electromagnetic field. As predicted by the theory, the amplitude of the luminescence spectrum of a given type of dye molecules increases with the refractive index of the microemulsion while the amplitude of the absorption spectrum remains almost unchanged. The various experimental results are also used to evaluate the radiative lifetimes of the dye molecules in the various microemulsions using three different approaches: ~i! from the luminescence decay times using a Fermi’s golden rule description of the spontaneous emission process taking into account the variations with the surrounding dielectric medium of both the local electromagnetic field and the density of available photon modes, ~ii! from the variation of the intensity of luminescence as a function of the luminescence decay time, and ~iii! from the absorption spectra using a modified Einstein relation between absorption and emission. An excellent agreement between the three methods is found for Sulforhodamine 101. For Sulforhodamine B, there are discrepancies between the values obtained from the luminescence and absorption measurements. @S1050-2947~99!00206-1#
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Spontaneous emission of dye molecules as a function of the surrounding dielectric medium
Journal of Luminescence, 1998Co-Authors: G. Lamouche, P. Lavallard, Thierry GacoinAbstract:Abstract We study the spontaneous emission of Sulforhodamine B and Sulforhodamine 101 molecules solved in water droplets (reversed micelles) that are stabilized by a surfactant and suspended in various mixtures of heptane and toluene. The experimental characterization includes measurements of absorption spectra, luminescence spectra and luminescence decay times. The various experimental results can be used to compute the radiative lifetimes of the dyes in the various solvents: (i) from the variation of the luminescence decay time, (ii) from the absorption spectra using the Strickler-Berg formula, and (iii) from the variation of the intensity of luminescence as a function of the luminescence decay time. An excellent agreement between the three methods is found for the Sulforhodamine 101 molecule. For the Sulforhodamine B molecule, all but the Strickler Berg formula agree very well.
