High-Power LED-Based Light Source for Determining the Efficiency of Photosensitizers against Cell Cultures

Drug development involves assessing the effect of new compounds on cell cultures. For some compounds, this assessment assumes additional influence on cells, such as lighting. The aim of this work is to develop a light source for uniform irradiation of cell cultures in plates and to determine the efficiency of new photosensitizers (PS). The designed scheme of the light source provides uniform irradiation of a 96-well plate with irradiance up to 76 mW/cm2, while temperature values do not exceed 43°C, which allows one to use it for activating PS. To test the operating modes of the source, zinc phthalocyanine with cholinyl substituents (cholosens) and HEK-293 or A431 cell cultures were used as a model object. Dependences of cell survival on the irradiation time and PS concentration were determined, and fluorescence images of a chemical trap for active oxygen species in cells experiencing oxidative stress due to the photodynamic effect of PS were obtained. The results indicate a more than twofold difference in survival between cells in experimental and control wells as well as uniform irradiation of all wells of the plate.