Prolonged Luminescence Kinetics of Erythrosine in the Breast Tissue in vitro

The kinetics of delayed fluorescence and phosphorescence of the photosensitizer erythrosine in fragments of normal tissues and malignant tumors of breast of the oncological dispensary patients was studied in vitro. It was shown that the kinetics of delayed fluorescence of the dye was formed as a superposition of signals of thermally activated luminescence and glowing resulting from singlet-triplet annihilation of photosensitizer molecules and singlet oxygen. Quenching of the annihilation component of delayed fluorescence was detected when molecules were excited by a series of pulses with a frequency of 5–10 Hz. The shape of the delayed fluorescence curve and the intensity and duration of the afterglow of dye molecules were determined by the ratio of the rates of oxygen consumption/restoration in tissues. The correlation of delayed fluorescence indices with the clinical and morphological characteristics of tumors has been established; the application of the results in optical express diagnostics of tissues is discussed.