In vitro photodynamic activities of zinc(II) phthalocyanines substituted with pyridine moieties

Abstract

Phthalocyanines are promising second-generation photosensiisers for photodynamic therapy (PDT) as a result of their strong bsorption in tissue-penetrating red light, easy modification and igh efficiency of generating singlet oxygen. To this date, three lass of metallophthalocyanines have been used in clinical and linical trials, they are silicon(IV) phthalocyanine, zinc(II) phthaloyanine and aluminum(III) phthalocyanine, respectively. However, he main problems related to phthalocyanine derivatives are their ow solubility in biological media and poor specific retention in he malignant tissue. Pyridine derivatives are a kind of important harmaceutical intermediates, they have excellent biocompatibilty because that they can form hydrogen bonds with the biological acromolecules by the basic nitrogen atom in their structure [1]. n this report, we describe the in vitro photodynamic activities of wo novel zinc(II) phthalocyanines substituted with pyridine moities at the peripheral and -position, respectively. The results hows that the tetra-substituted zinc(II) phthalocyanine TP1 xhibits a low aggregation tendency in the biological media, a high