Preparation of a118Te/118Sb radionuclide generator

The development of a new radionuclide generator, based on¹¹⁸Te/¹¹⁸Sb, has been studied. The 3.5 minute¹¹⁸Sb daughter activity decays principally by positron emission and has potential use as a flow tracer. The¹¹⁸Te parent is conveniently produced by proton bombardment of antimony targets. A simple and efficient scheme for the separation of radiotellurium from proton-irradiated antimony targets has been developed, and thin-target cross sections for¹²¹Sb(p, 4n)¹¹⁸Te and competing reactions have been determined. For antimony targets irradiated with 46 MeV protons, the yields (mCi/g Ah) of¹¹⁸Te,^119mTe and¹¹⁹Te were measured to be 0.71, 0.33 and 1.9, respectively. The adsorption and elution characteristics of activated carbon for tellurium have been evaluated for use as a column chromatography adsorbent in a¹¹⁸Te/¹¹⁸Sb generator. The conditions for optimal¹¹⁸Sb elution and minimal¹¹⁸Te breakthrough for promising systems are presented.