SPECTROSCOPIC CHARACTERIZATION OF FLUORINATED HYDROGENATED MIXED VESICLES CONTAINING FLUORINATED MN(III)-PORPHYRIN/

Mixed fluorinated/hydrogenated vesicles prepared with n-dodecylbetaine and the ammonium salt of a perfluoropolyether carboxylate were able t o be loaded with 10,15,20-tetrakis(4-perfluorooctylphenyl)porphyrin an d with its Mn(III) salt. The synthesis and the characterization of bot h long chain tetrapyrrole compounds are described. The structural feat ures of the loaded vesicle systems were studied by light scattering an d small angle neutron scattering and compared with those of plain vesi cles. UV-Vis spectroscopy and electron spin resonance of added nitroxi des gave details on the location and on the intermolecular interaction s of the inserted molecules. The porphyrins were inserted in the vesic le membrane with resultant bending of the limiting vesicle surface. Th e consequent decrease of the mean radius was typically from 800-900 to 550-650 Angstrom, depending on the specific system composition. Howev er the overall spherical shape and the characteristic bilayer structur e was maintained. A significant aggregation of both Mn(III) porphyrin and metal free porphyrin was apparent from the UV-Vis spectra. The res ults presented in this paper were compared with those obtained after i nsertion into the same vesicle systems of Cu(II) tetraazaporphyrin wit h completely hydrogenated side chains. These self-assembled systems ma y therefore be considered as promising tools to act as biomolecule car riers. (C) 1998 Elsevier Science S.A. All rights reserved.