Non-aggregated zwitterionic Zinc(II) phthalocyanine complexes in water with high singlet oxygen quantum yield

• Published in: Dyes and pigments 2019-01, Vol.160, p.267-284
• Main Authors: Dilber, Gülsev, Durmuş, Mahmut, Kantekin, Halit
• Format: Article
• Language: English
• Subjects: Photochemical; Photodynamic therapy; Photophysical; Phthalocyanines; Water soluble; Zwitterion
• ISSN: 0143-7208; 1873-3743
• DOI: 10.1016/j.dyepig.2018.08.019

Syntheses of non-peripheral (4) and peripheral (5) 2-(4-methyl-1,3-thiazol-5-yl)ethanol substituted zinc (II) phthalocyanines were achieved in this study. These zinc(II) phthalocyanines were converted to their quaternized ionic (4a and 5a) and zwitterionic (4b and 5b) derivatives. The structures of these novel compounds were characterized by elemental analysis and different spectroscopic methods such as FT-IR, UV-Vis, NMR and mass. General trends were examined for aggregation behaviours, photochemical and photophysical properties of the non-ionic zinc (II) phthalocyanines (4 and 5) in DMSO and their water soluble cationic (4a and 5a) and zwitterionic (4b and 5b) derivatives in both of DMSO and phosphate solution (PBS). The effect of different position and quaternization or zwitterionization of the binding groups on the photophysical and photochemical properties were also announced. Water soluble zwitterionic compound 4b exhibited very high singlet oxygen generation which makes it ideal photosensitizer in treatment of cancer by photodynamic therapy method. The fluorescence of the tetra-substituted zinc (II) phthalocyanines (4 and 5) are effectively quenched by addition of 1,4-benzoquinone (BQ). Furthermore, the water soluble phthalocyanine derivatives (4a, 5a, 4b and 5b) can bind to bovine serum albumin (BSA) which is a blood plasma protein. [Display omitted] •Synthesis of substituted phthalonitrile derivatives.•Synthesis of non-peripheral and peripheral 2-(4-methyl-1,3-thiazol-5-yl)ethanol substituted zinc (II) phthalocyanines.•Synthesis of cationic and zwitter ionic derivatives of the phthalocyanines.•Investigation of aggregation properties.•Investigation of singlet oxygen generation, fluorescence and BSA binding properties.