Effect of Some Substituents Increasing the Solubility of Zn(II) and Al(III) Phthalocyanines on Their Photophysical Properties

Abstract

Water solubility of phthalocyanines (Pcs) usually increases by the introduction of charged or carboxy substituents in the peripheral positions of the macrocycle. As a result, such structural changes influence their photophysical and photochemical properties as photosensitizers. Phthalocyanines substituted with four or eight terminal carboxyl groups and having in some cases additional eight positive charges (water soluble phthalocyanines) were studied in order to evaluate the spectroscopic and photophysical effects of these side residues on the chromophore properties. The quantum yield of singlet oxygen (1O2) generation, the triplet-triplet absorption, and the transient absorption spectra were measured and linked to the structure of the substituents. It was shown that charged substituents did not change the quantum yields of 1O2 generation but decrease its lifetimes. The introduction of the charged substituents not only increases the water solubility but also significantly changes absorption, fluorescence, and transient absorption spectra of water soluble Pcs.

Targeted photodynamic therapy as potential treatment modality for the eradication of colon cancer and colon cancer stem cells

“…Such modifications can tune the water solubility and aggregation of the PCSs, without significantly affecting its photophysical properties. 79…”

Synthesis of Water-Soluble Phthalocyanines and Modification of their Peripheral Fragments as a Method of Directed Changes in Lipophilic-Hydrophilic Properties

“…Подобными свойствами обладают и многочисленные фталоцианины с разнообразными периферическими заместителями. В последнее время постоянно появляются сообщения об успехах в синтезе водорастворимых фталоцианиновых лигандов и комплексов, которые достигаются введением в молекулу периферийных заместителей катионного или анионного типа, содержащих структурные фрагменты, обеспечивающие гидрофильность лигандов и комплексов [8][9][10][11]. Чрезвычайно желательным свойством идеального сенсибилизатора является одновременная водо-и жирорастворимость.…”

Modulation of internal conversion rate and nonlinear absorption in meso-tetraphenylporphyrins by donor/acceptor substitutes

“…Understanding the basic optical nonlinearities of these tetrapyrrolic derivatives is of considerable interest due to their widespread application potential [28][29][30]. The most investigated photophysical property is RSA due to its potential use in pulse sensors or in optical limiting devices for protecting sensitive optical components or human eyes from laser-induced damage [7,10,16].…”