Anion-exchange column chromatography of EDTA, DTPA, and the DTPA complexes of calcium and plutonium

An anion-exchange column system is described which is capable of separating ethylenediaminetetraacetic acid (EDTA) from diethylenetriaminepentaacetic acid (DTPA) in the form of their calcium chelates. In addition, distinct elution positions are demonstrated for: (1) the unchelated form of DTPA; (2) the calcium chelate of DTPA; and (3) the plutonium(IV) chelate of DTPA. Preparation and chromatograhy of a doubly labeled complex of /sup 239/Pu(IV) and /sup 14/C-labeled DTPA ((/sup 14/C)DTPA) are also described. Separation of (/sup 14/C)DTPA from autoradiolytic breakdown products found in high-specific-activity preparations is demonstrated. This chromatograhic procedure has the potential for use in studying the metabolism and mechanism of action of DTPA and for evaluating the purity of (/sup 14/C)DTPA preparations.