Optimized anion exchange column isolation of zirconium-89 (⁸⁹Zr) from yttrium cyclotron target: Method development...

Zirconium-89 (⁸⁹Zr), produced by the (p, n) reaction from naturally monoisotopic yttrium (^natY), is a promising positron emitting isotope for immunoPET imaging. Its long half-life of 78.4 h is sufficient for evaluating slow physiological processes. A prototype automated fluidic system, coupled to on-line and in-line detectors, has been constructed to facilitate development of new ⁸⁹Zr purification methodologies. The highly reproducible reagent delivery platform and near-real time monitoring of column effluents allows for efficient method optimization. The separation of Zr from dissolved Y metal targets was evaluated using several anion exchange resins. Each resin was evaluated against its ability to quantitatively capture Zr from a load solution high in dissolved Y. The most appropriate anion exchange resin for this application was identified, and the separation method was optimized. The method is capable of a high Y decontamination factor (>10⁵) and has been shown to remove Fe, an abundant contaminant in Y foils, from the ⁸⁹Zr elution fraction. Finally, the method was evaluated using cyclotron bombarded Y foil targets; the method was shown to achieve >95% recovery of the ⁸⁹Zr present in the foils. The anion exchange column method described here is intended to be the first ⁸⁹Zr isolation stage in a dual-column purification process.