The optimal procedure for preparation of Tc-99m(V)-dimercaptosuccinic acid (DMSA) from the Tekhnemek reagent was proposed. The yield of tumorotropic complex in alkali media (pH greater than or equal to 9) is about 90%. An analytical procedure was developed to determine the radiochemical purity (RCP) and components of tumorotropic preparation. The spectrophotometric and chromatographic data for Tc-99 + Tc-99m showed that the oxidation state of technetium in the "alkali" complex is 5+. The reduction of technetium-99m to form the Tc(V)-DMSA complex is completed in 30 min. The content of tumorotropic complex in the preparation based on Tc-99m with a volume activity from 1 to 10 mCi ml(-1) remains constant.

By means of IR spectroscopy it was established that the complex formation of (ethylene-bis(nitrilodimethylene))- and ((oxydiethylene)bis(nitrilodimethylene))-tetrakisphosphonic acids with indium is effected by the interaction of the metal with the nitrogen and oxygen atoms. The relative proportion of the complexes of indium with ((oxydiethylene)bis(nitrilodimethylene))tetrakisphosphonic acid in which a nitrogen atom is coordinated by metal falls with decrease in pH.