Penetration of radionuclides across the skin: Concentration dependence of60Co permeation

Co²⁺ ion penetration at different concentrations across animal models of human skin-five days old rat skin (without hairs) and nine days old rat skin (with hairs)—was studied in vitro in vertical diffusion cells. The results showed that the permeated amounts of Co²⁺ ions are proportional to its concentration in donor solutions, whereby permeated fractions are higher at lower concentrations. Results confirmed that the most important barrier against the penetration of ions is horny layer of the skin.