Ultrarapid Purification of Manganese-52 from Chromium-52 Targets via Potentiostatic Anodic Dissolution and Chelation...

Manganese-52 (⁵² Mn, t _1/2 = 5.6 days) is an attractive positron-emitting isotope for integrated positron emission tomography and magnetic resonance imaging. Its availability, however, is constrained by the challenge of achieving rapid, high-purity separation from cyclotron-irradiated chromium-52 (⁵²Cr) targets. This study presents an ultrarapid, two-step purification strategy that couples potentiostatic anodic dissolution with single-column chelation ion chromatography. Electrochemical analysis indicates that the Mn target undergoes rapid oxidation and is dissolved as ammine complexes in an ammonium/ammonium chloride buffer (pH 8) at 0.7 V (vs Hg/HgO), whereas the Cr target remained almost passivated and trace Cr leached was precipitated on the target surface as Cr-(OH)₃ under identical conditions. The sharp decrease in anodic current density, induced by the distinct dissolution behavior of Mn/Cr targets, provides a convenient real-time endpoint for assessing complete Mn dissolution. The resulting analyte was then loaded directly onto iminodiacetate resins (Diaion CR11) and eluted with HCl, converting the ammine complexes to hydrated Mn²⁺. Simulated experiments achieved a Mn chromatographic recovery of 98.65% with >99.99% purity within 30 min. This integrated approach offers significant advantages in processing speed and recovery yield over conventional methods, demonstrating high potential for the production of clinical ⁵² Mn.