Photophysical properties of a water-soluble adjacently substituted bisnaphthalophthalocyanine

Spectral properties of a water soluble metal free tetracarboxyphenoxy bisnaphthalophthalocyanine (3) were studied in water and organic solvents. It was found that in protic solvents, complex 3 was highly aggregated. The surfactant, Triton X100, and bovine serum albumin (BSA) do not effect disaggregation while cetyl trimethylammonium chloride (CTAC) caused the molecule to disaggregate. The fluorescence quantum yields were higher in the presence of CTAC. Studying the interaction of BSA with complex 3 using fluorometry revealed that BSA is highly quenched by the latter. A 1: 1 stoichiometric binding ratio between BSA and the PC was found. Triplet quantum yields in water containing CTAC were higher than in organic solvents. Copyright (c) 2005 Society of Porphyrins & Phthalocyanines.