Europium-Containing Conjugate for Photodynamic Therapy of Malignant Neoplasms

The rapid growth in the number of oncological diseases justifies the need to create new therapeutic agents and methods. Photodynamic therapy has a wide range of treatments for superficial diseases due to the inability to penetrate more than 3 mm of laser light into tissues. The aim of the study was to characterize the physicochemical properties of a new PEI-E6-DTPA-FA-Eu molecular conjugate based on the europium-modified Сhlorin E6 photosensitizer and to evaluate its phototoxic effect on Ehrlich ascitic tumor cells. It has been established that under 5-minute irradiation with a wavelength of 645 nm and an energy of 6 J/cm 2 , the synthesized molecular conjugate PEI-E6-DTPA-FA-Eu generates reactive oxygen species 5.1 times more intensively than free Chlorin E6. On the 4th day after photodynamic exposure with PEI-E6-DTPA-FA-Eu, the cell death rate was 75%, while with Chlorin Е6 it was only 24%.