Solubilization and Photochemical Stability of Octa[(4′-Benzo-15-Crown-5)Oxy]-Phthalocyanines in Aqueous Micellar Solutions

Abstract

Methods of absorption and fluorescence spectroscopy and, in some cases, small angle X-ray scattering, are used to study solubilization and supramolecular organization of octa[(4'-benzo-15-crown-5)-oxy]phthalocyanines (Pc), H₂cr₈Pc, and Mgcr₈Pc in an aqueous medium in the presence of polyelectrolytes, sodium polystyrene sulfonate, and sodium carboxymethyl cellulose or their mixtures with anionic surfactants: sodium dodecyl benzene sulfonate and sodium deoxycholate. The obtained results indicate the appearance of a monomeric, fluorescent state of Mgc₈Pc in the presence of sodium polystyrene sulfonate and at the further increase in its concentration with an increase in the solution ionic strength and addition of anionic sodium deoxycholate. In all cases, the monomeric state of Mgcr₈Pc is confirmed by the data of fluorescence spectroscopy. Photobleaching of Mgcr₈Pc solubilized in the monomer form is observed in aqueous micellar solutions of sodium dodecylsulfate and sodium dodecyl benzene sulfonate. In the presence of PSS/NaCl, aqueous solutions of Mgcr₈Pc were also studied using dynamic light scattering and small-angle X-ray scattering.