Amino-functionalized water-soluble zinc phthalocyanines: Synthesis, photophysical, photochemical and protein binding properties

Tetra-peripherally substituted symmetrical and low symmetrical Zn (II) phthalocyanines containing 2-[2-(2-ethoxyethoxy)ethoxy]-1-[2-((2-ethoxyethoxy)-ethoxy)ethoxymethyl] ethyloxy and [2-(tert-butoxycarbonyl)amino]ethoxy groups, as well as their deprotected amino-functionalized derivatives were synthesized for the first time. These novel zinc phthalocyanines were characterized by elemental analysis and spectroscopic methods including FT-IR, 1H and 13C NMR, MALDI-TOF, UV–vis. Their photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen and photodegradation quantum yields) properties were investigated in DMSO, in water and in water + triton X-100 solutions for comparison of solvents and aggregation effects. Effects of symmetries of the phthalocyanine molecules on these properties were also revealed. The fluorescence quenching of these Zn (II) phthalocyanines upon addition of 1,4-benzoquinone were examined in DMSO. Binding study of these phthalocyanine photosensitizers to bovine serum albumin one of the blood carrier proteins, was also examined in this study.