Direct photogeneration of singlet oxygen in biological medium for cancer therapy

Advances in cancer treatment require continuous improvement and the search for new therapies. Methods for direct photogeneration of singlet oxygen in tissue using IR lasers may be an effective alternative to photodynamic tumor therapy. The physical limitation for the direct photogeneration of singlet oxygen in a biological medium is the low absorption cross section of molecular oxygen. To overcome this limitation, it is necessary to use infrared radiation with a high power density, which in a living system is limited by thermal effects. A promising direction in the development of this approach could be the use of pulsed laser irradiation. By solving the problem of direct photogeneration of cytotoxic concentrations of singlet oxygen in a biological environment, including tumor tissue, without simultaneous heating to biocritical temperatures, it is possible to develop new effective and safe methods for the treatment of malignant neoplasms. Key words: single oxygen, direct photogeneration, reactive oxygen species, cancer therapy, photobiomodulation.