The Influence of Dimerization of Water-Soluble Metalloporphyrins as Photosensitizers on the Efficiency of Generation of Singlet Oxygen

摘要

Quantum yields (Φ_Δ) for the generation of singlet oxygen sensitized by Pd(II) complexes of water-soluble porphyrins: meso-tetrakis(4-N-methylpyridyl)porphine [PdTMPyP]~(4+) (Φ_Δ - 0.9), meso-tetrakis(4-N,N,N-trimethylaminophenyl)porphine [PdTTMAPP]~(4+) (Φ_Δ = 0.8), meso-tetrakis(4-carboxyphenyl)porphine [PdTCPP]~(4-) (Φ_Δ = 0.7), and meso-tetrakis(4-sulfonatophenyl)porphine [PdTSPP]~(4-) (Φ_Δ = 0.5) were determined using a chemical method. It was found that the dimerization and aggregation of metalloporphyrins greatly influence the Φ_Δ value. The quantum yields evaluated for the formation of singlet oxygen sensitized by metalloporphyrin monomeric and dimeric forms are Φ_(Δ,M) ≈ 0.9 and Φ_(Δ,D) ≈ 0.2, respectively, and do not depend on the porphyrin nature.