Buffer Action of Reversed Micelles
نویسنده
چکیده
The optical properties (absorption and fluorescence) of fluorescein sodium were investigated with changing the bulk pH value in aqueous, water-methanol mixed and dodecylammonium propionate reversed micellar solutions. A strong buffer action was found in the reversed micellar solutions. The pK a values for the equilibrium between fluorescein monoand di-anions in the ground and excited singlet states highly decreased in the reversed micellar solutions compared with those in non-micellar solutions. The micellar buffer action strongly affected the initial rate of the 1,3-diphenylisobenzofuran oxidation caused by the photosensitization of fluorescein. The buffer action was closely related to the solubilized water content.
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