Abstract 99mTc, the daughter product of 99Mo, is a γ-emitting radionuclide with essential diagnostic applications in nuclear medicine. In this paper, an accelerator-based method (100Mo (γ, n)99Mo) for production of 99Mo and 99mTc has been explored. Approximately 68.3 MBq of 99Mo was successfully produced by the irradiation of 100Mo metallic target for 40 h using electron beam with energy of 50 MeV and current of 0.2 μA at electron linear accelerator (Institute of Modern Physics, Chinese Academy of Sciences, IMPCAS). Different types of 99Mo/99mTc generators were prepared using hierarchical macro/mesoporous γ-Al2O3 (HMMA) as column adsorbent, and their performances were evaluated for over one week. 99Mo/99mTc generator with a column (3 mL, 4.2 × 0.95 cm) packed with 0.6 g HMMA exhibited excellent eluting performance. 99mTc could be collected within 4.0 mL of saline solution with high purity, and the elution efficiency could reach >85 %. Furthermore, 99Mo breakthrough in the eluates was negligible (<2 × 10−3 %) and concentration of impurity (<10 ppm) was acceptable. Finally, the enriched 100Mo was eluted from the spent 99Mo/99mTc generator using 1.0 mol/L ammonium hydroxide, and then reduced by high-temperature hydrogen reduction process with a total recovery of 95.3 %. This work demonstrated that the preparation of 99Mo via 100Mo (γ, n)99Mo reaction and isolating 99mTc using HMMA column chromatography have a potential in application.
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