Water-soluble porphyrin photosensitizers containing electron-withdrawing and electron-donating groups for photodynamic therapy

Abstract

Photodynamic therapy is used to treat a variety of cancers. In this paper, water-soluble porphyrin photosensitizers (H2P1[Formula: see text]H2P3) for photodynamic therapy were synthesized, containing three groups -CH3, -CN, and -CF3. Density functional theory is used to optimize the structure of H2P1-H2P3 and calculate the [Formula: see text]E value. The smaller the value of [Formula: see text]E, the more favorable the electron transfer and thus the higher activity of the porphyrin photosensitizers. Due to the electron-withdrawing groups of -CN and -CF3, H2P2 and H2P3 have lower [Formula: see text]E values, higher reactive oxygen species yields compared with H2P1. The H2P2 porphyrin photosensitizers showed positive photodynamic therapeutic activity against hepatocellular carcinoma cells (HepG2) and good compatibility with human umbilical vein endothelial cells (HUVECs) by cellular anticancer activity assay. The anti-cancer mechanism of PSs was explained by living and dead cell staining experiment and intracellular reactive oxygen species experiment. PSs produced reactive oxygen species (ROS) in cancer cells under light irradiation, which induced cancer cell apoptosis.