Objective: Positron-emitted Zr-89 (Zirconium, half-life 3.27 days) in clinic has recently been reported to be particularly effective at PET imaging. Such Zr-89 depends on a good bifunctional chelator and proper biomolecule (peptides, antibody, etc.) for specific binding in cell. The aim of our study, thus, was to widen the use of Zr-89 in Korean clinic with development of PET technology.
Material & Method: Zr-89 was generated by nuclear reaction of 50 MeV cyclotron (Scantronix co.) in KIRAMS, which was used as target material of yttrium foil. The nuclear reaction was carried out Y-89(p,n)Zr-89 under irradiation of proton beam (20 μA, 18 MeV) for 2 hours. The purification of Zr-89 was performed with a specific Sep-PaK column (hydroxamate resin). On this column, Zr-89 oxalate was rapidly prepared as high radiochemical purity.
Result: Zr-89 oxalate was easily prepared by short column, and the radiochemical purity was over 99%. The radiochemical yield of product was obtained as radioactive solution of 9-13 mCi in hydrochloric acid (1 mL, 1 M). Zr-89 was showed the specific gamma-energy of both 511 and 909 KeV as reported previously. Zr-89 oxalate, thus, was successfully exhibited good PET imaging of bone marrow in mouse. Zr-89 was further studied the ability of PET imaging using phantom and microPET scanner.
Conclusion: The development of Zr-89 oxalate may be extended to the studies of new radiotracer for PET molecular imaging.