An EPR and Optical Spectroscopy Study of the Effect of Laser Radiation on Biological Tissues

The formation of radicals upon UV (248 nm) and IR (1.56 μm) laser irradiation of some biological tissues (cartilage, bone tissue, fish scale) and their components (chondroitin sulfate, collagen) was studied by the EPR technique. The radical decay kinetics in bony tissue specimens after their irradiation with UV light were described. By the spin trapping technique, it was shown that radicals were not produced during IR (1.56 μm) laser irradiation of cartilaginous tissue. A change in optical absorption spectra and the dynamics of optical density of cartilaginous tissue, fish scale, and a collagen film under exposure to laser radiation (248 nm) in an air, oxygen, and nitrogen atmosphere was studied.