(90)Y microspheres prepared by sol-gel method, promising medical material for radioembolization of liver malignancies.

Abstract A new technology for the production of radiopharmaceutical 90 Y microspheres in the form of spherical yttrium oxide grains obtained by sol-gel method has been described. The authors present and discuss the results of investigations performed in the development of new production technology of yttrium microspheres and determination of their physic-chemical properties. The final product has the structure of spherical yttrium oxide grains with a diameter 25–100 μm, is stable and free from contaminants. Irradiation of 20 mg samples of grains with diameter of 20–50 μm in the thermal neutron flux of 1.7 × 10 14  cm − 2  s − 1 at the core of MARIA research nuclear reactor allowed to obtain microspheres labelled with the 90 Y isotope on the way of the nuclear reaction 89 Y(n, ɤ) 90 Y. Specific activity of irradiated microspheres has been determined by application of absolute triple to double coincidence ratio method (TDCR) and has been evaluated at 190 MBq/mg Y. 90 Y microspheres prepared by the proposed technique can be regarded as a promising medical material for radioembolization of liver malignancies.