Synthesis of New Adsorbents for Mo as an RI Generator

Abstract

Technetium-99m is widely used in the world for the purpose of diagnosis in nuclear medicine. The ^99mTci s obtained from the parent nuclide of ⁹⁹Mo adsorbed in a generator. Synthesis of Zr-based i norganic polymer, which has extremely high adsorbability of Mo and is applicable to the ⁹⁹Mo product of low specific activity, was attempted.
Five kinds of the precur sors for Zr-based-polymer adsorbents were prepared by the hydrolysis of ZrCl₄ and the reactions between ZrCl₄ and poly (vinyl alcohol), isopropyl alcohol, ethylene glycol orglycerol. These precursors were converted into adsorbents by heating in Ar gas flow. Their structures were presumed from the pyrolysis behavior. Adsorption capacities of Mo of these adsorbents were dependent on the number of Cl atoms bonded to Zr atom in the molecules. It was suggested that the adsorption of Mo to these adsorbents was proceeded by chemical reaction between two neighboring Zr-Cl bonds and MoO₄^2-. The adsorbent prepared from ZrCl₄ and isopropyl alcohol showed the highest adsorption capacity of Mo (about 250 mg/g adsorbent) and ^99mTc yield (about 80%) in eluant.