Singlet oxygen producing sensitizers on solid inorganic hosts: photodisinfecting materials and probes.

Abstract:
The core of the project is design, preparation, photophysical characterization and final testing of novel photoactive materials. These materials consist of singlet oxygen 1O2 producing photosensitizers intercalated into layered materials (smectites, hydrotalcites) or embedded into silica matrices. The selected sensitizers are meso-substituted porphyrins and phthalocyanines, both free ligands and metallocomplexes, whose photophysical/photochemical properties can be finely tuned by peripheral substituents modifying the charge, charge sign and hydrophobicity. Smectites can be used for hosting cationic species whereas hydrotalcites will be intercalated by anionic species. The same sensitizers will be embedded into silica sol-gel matrices. Sincethe photophysical properties of the sensitizers in the hosts are profoundly changed, stationary and time-resolved spectral methods (UV-vis, IR, luminescence, EPR) will be used for detailed ascertainment of the changes. Generation of O2 assigns the materials as well for application as photo-desinfecting and cell killing materials.