Chromatographic separation of technetium species

In this work an attempt is made to have a closer look at technetium species (TcX) induced by spinach plants, grown on TcO4- containing nutrient solutions. To this end, size-exclusion chromatography (SEC) and reversed-phase ion-pair chromatography (RP-IPC) were used; the performance was established with model compounds, i.e. anionic Tc-DTPA and cationic Tc-cyclam, used as mimics for TcX. Under conditions applied, the information retrieved from high performance RP-IPC was minimal due to strong interactions of the technetium species with the Nucleosil C18 stationary phase. However, in low-pressure SEC non-size effects allowed differentiation of TcX into two distinct classes of technetium compounds, i.e. TcX1, and TcX2. From retention behaviour in SEC, it was possible to speculate on the chemical properties of these two technetium species. (author)