The effect of nanometer particles of titanium oxide on the protective properties of skin in the UV region

This paper discusses the efficiency of the attenuation of UV radiation by nanoparticles of titanium oxide (TiO2) incorporated into the horny layer of the skin. The distribution of TiO2 particles was determined experimentally. A program implementing the Monte Carlo method was used to model photon propagation in a 20-µm thick horny layer of the skin, partially filled with TiO2 particles. The dependences are obtained for the transmitted, reflected, and absorbed components of UV radiation with a wavelength of 310 nm as a function of the concentration of TiO2 particles of various sizes (40-175 nm). It is established that the most efficient particles for protecting the deep layers of skin containing living and, in particular, immune-competent cells from UV radiation are particles 62 nm across.