Formation of a Radioactive Label in Carbon Nanostructures by Alpha-Particles Accelerated in a Cyclotron

The development of methods for the quantitative determination of carbon nanostructures (nanodiamonds, nanotubes, fullerenes, etc.) in various media is an urgent task of modern science about nanoparticles and nanomaterials, ecology and occupational health, medicine, experimental biology, and pharmacology. A large number of technical solutions are based on the introduction into the studied carbon nanostructures of various markers in the form of atoms of other elements, radioactive and isotopic inclusions, conjugation with biologically active structures, or on the introduction of other easily detectable labels. The use of a radioactive marker has a number of advantages. Herein are presented the development and testing of the method allowing one to obtain carbon nanostructures labeled with a radioactive isotope 7Be formed from nuclei 12C as a result of irradiation of the initial carbon structures with high-energy α-particles accelerated at the cyclotron. It is shown that, as a result of irradiation of samples of pure carbon with natural isotopic composition, an intense spectral line of γ-radiation with an energy of 478 keV appears in them, which corresponds to the isotope 7Be generated during a nuclear reaction of 12С (α,9Be)7Be. The sensitivity of modern, commercially available γ-spectrometers makes it possible to use radioactive labels with activities at the level of natural radioactivity in the human body and conduct experiments without danger to the health of personnel.