Successful Labeling of^99mTc-MDP Using^99mTc Separated from⁹⁹Mo Produced by¹⁰⁰Mo(<i>n</i>,2<i>n</i>)⁹⁹Mo

Abstract

We have for the first time succeeded in separating 99m Tc from a MoO 3 sample irradiated with accelerator neutrons free from any radioactive impurities and in formulating 99m Tc-methylene diphosphonate ( 99m Tc-MDP). 99 Mo, the mother nuclide of 99m Tc, was produced by the 100 Mo( n ,2 n ) 99 Mo reaction using about 14 MeV neutrons provided by the 3 H( d , n ) 4 He reaction at the Fusion Neutronics Source of Japan Atomic Energy Agency. The 99m Tc was separated from 99 Mo by sublimation and its radionuclide purity was confirmed to be higher than 99.99% by γ-spectroscopy. The labeling efficiency of 99m Tc-MDP was shown to be higher than 99% by thin-layer chromatography. These values exceed the United States Pharmacopeia requirements for a fission product, 99 Mo. Consequently, a 99m Tc radiopharmaceutical preparation formed by using the mentioned 99 Mo can be a promising substitute for the fission product 99 Mo, which is currently produced using a highly enriched uranium target in aging research reactors. A longstanding problem to ensure a reliable and constant supply of 99 Mo in Japan can be partially mitigated.