Comparative evaluation of singlet oxygen generation of new tetra-schiff base substituted zinc phthalocyanine by photochemical and sonophotochemical techniques

Abstract

Phthalocyanines have been extensively used as sensitizers in therapeutic applications mostly in photodynamic therapy (PDT) and sonodynamic therapy (SDT) due to their high singlet oxygen production capacity and other unique properties. Although singlet oxygen production can be increased with the sonophotodynamic therapy (SPDT), which is a combination of PDT and SDT applications and emerges as a technique that compensates for the shortcomings of these methods, studies on phthalocyanines using the SPDT are quite limited in the literature. Keeping this in mind, this study focused on both the synthesis and structural characterization of the novel tetra-schiff base substituted zinc (II) phthalocyanine compound and also revealing its potential to improve singlet oxygen production by sonophotochemical technique.Comparative measurements showed that while the singlet oxygen quantum yield of the synthesized phthalocyanine compound was calculated as 0.66 by photochemical measurement using only light irradiation, this value increased to 0.91 by sonophotochemical measurement after dual effect of light and ultrasound.This result shows that the sonophotochemical method exhibits a more effective therapeutic effect than the photochemical method and that the synthesized compound can be used as a promising SPDT agent in vitro or in vivo future studies.