Abstract: A method of reducing the pertechnetate in TcO.sub.4.sup.- comprises mixing together an aqueous solution of pertechnetate, e.g. the eluent from a technetium generator, metallic tin or an alloy thereof as a reducing agent for the pertechnetate, and a soluble salt of a metal below tin in the electrochemical series, e.g. copper, as an activator for the tin metal reducing agent. A complexing agent for the reduced technetium or a colloid stabilizer may also be included. The pH is preferably 3 to 12. Also claimed is a closed container containing the tin reducing agent, the activator, and the complexant or colloid stabilizer if used, preferably in a freeze-dried sterile state, to which the pertechnetate solution may be added.

Abstract: A closed container for producing, on introduction of a solution of technetium-99m as pertechnetate, technetium in a form suitable for diagnostic scanning, contains under sterile conditions tin or a tin-containing alloy as a reducing agent for the pertechnetate and a complexant for the reduced technetium, the contents of the container being present in a dry state. In the method, the pertechnetate solution, suitably the eluate in isotonic saline from a technetium-99m generator, is added to the container and the complex recovered therefrom.

Abstract: The invention provides a method and apparatus for preparing aqueous solutions of technetium-99m pertechnetate. In a preferred embodiment, the eluate from a technetium-99m generator is contacted with a cation-exchange resin having adsorbed thereon a cation which forms an insoluble salt with the anion of the generator eluate, whereby there is obtained an aqueous solution of the pertechnetate in water. The solution may be concentrated by adsorption of the pertechnetate on alumina, followed by desorption using a smaller volume of aqueous electrolyte.