Search for plant-induced technetium species with size-exclusion and reversed-phase ion-pair chromatography

In this work an attempt is made to have a closer look at technetium species (TcX) induced by spinach plants, grown on TcO _? ⁴ 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 the 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 behavior in SEC, it was possible to speculate on the chemical properties of these two technetium species.