Magnesium octa[(4'-benzo-15-crown-5)oxy]phthalocyanine in phosphate buffer: Supramolecular organization, cytotoxicity and accumulation/localization in tumor cells of HeLa

Abstract

For the first time, magnesium octa[(4'-benzo-15-crown-5)oxy]phthalocyanine (Mgcr8Pc) was explored as a potential PDT agent. Presence of crown-containing fragments in the periphery of the tetrapyrrole macrocycle makes the compound soluble in water. Solutions of Mgcr8Pc in water and in phosphate buffer (PBS) are stable for a long time. Modification of Mgcr8Pc solutions in PBS with sodium deoxycholate led to partial monomerization of Mgcr8Pc and hence to formation of a fluorescent species. The cytotoxicity of Mgcr8Pc was determined with respect to HeLa cells and its accumulation/localization in the cells was studied by fluorescence microscopy. The increase in signal intensity indicates the accumulation of Mgcr8Pc in HeLa cells over time. The cell morphology was found to remain practically intact when subjected to Mgcr8Pc at concentration of 5.00 µM for 24 h. The results obtained allow us to continue the study of this interesting class of compounds.