β-MoO₃ Whiskers in ⁹⁹Mo/^99mTc Radioisotope Production and ⁹⁹Mo/^99mTc Extraction Using Hot Atoms

β-MoO₃ whiskers prepared by a thermal evaporation method and α-MoO₃ particles were irradiated in a nuclear reactor to produce ⁹⁹Mo/^99mTc radioisotopes via neutron capture. The irradiated targets were then dispersed in water to extract the ⁹⁹Mo/^99mTc isotopes. Of the ⁹⁹Mo formed in the β-MoO₃ whiskers, 64.0 ± 7.4% was extracted with water; by contrast, only 8.8 ± 2.6% of the ⁹⁹Mo formed in α-MoO₃ was extracted. By comparing these data to the ⁹⁸Mo concentration dissolved in water, we confirmed the hot-atom effect on both β-MoO₃ whisker and α-MoO₃ particle targets to transfer ⁹⁹Mo isotopes from irradiated samples to water. In addition, the β-MoO₃ whiskers exhibited a prominent hot-atom effect to transfer a higher ratio of ⁹⁹Mo isotopes into water. To the best of our knowledge, this research is the first demonstration of β-MoO₃ being used as an irradiation target in the neutron capture method. On the basis of the results, β-MoO₃ is considered a promising irradiation target for producing ⁹⁹Mo/^99mTc by neutron capture and using water for the radioisotope extraction process in the future.