Synthesis of new water soluble phthalocyanines and investigation of their photochemical, photophysical and biological properties

With the quaternized derivatives (4a and 5a), the synthesis of new Zn(II) and Co(II) phthalocyanines (4 and 5) substituted with 2-(azepan-1-yl)ethoxy moieties are reported. Photochemical and photophysical properties of quaternized Zn(II) and Co(II) phthalocyanines (4a and 5a) are investigated in both dimethyl sulfoxide (DMSO) and water, while non ionic derivatives in DMSO only. General trends are described for fluorescence quantum yields, fluorescence lifetimes, singlet oxygen quantum yields and photodegradation quantum yields. In this work, the effect of substituents and the nature of the metal atoms on the photochemical and photophysical parameters of new phthalocyanines are discussed. The quaternized compounds exhibit excellent solubility in water, making them potential photosensitizers for use in photodynamic therapy (PDT) of cancer. This study also showed that the water-soluble quaternized Zn(II) phthalocyanines strongly bind to blood plasma proteins such as bovine serum albumin (BSA).

Graphical abstractNovel phthalocyanines were synthesized and their photochemical and photophysical properties indicated that they can be used for PDT. In addition, it is found that they can be bound to BSA. Thus they can be transported in blood easily.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► In this study new ZnPc, CoPc and their quaternized derivatives were synthesized. ► Photochemical and photophysical properties of these compounds indicated that these are new candidates to be used in PDT. ► Binding of new compounds to BSA was also proved.