Production Process of 89Zr Based on C30 Cyclotron

Abstract

Due to the good decay modes and suitable half-life, 89Zr is widely used in the field of immune-PET imaging. The objective is to develop a new target system suitable for cyclotron nuclide production and to obtain a new method for batch production of 89Zr. Herein, two kinds of coin targets were designed and developed based on C30 cyclotron solid target system, and superior coin target structures were determined through irradiation verification. The yttrium foil was assembled in the coin target plate, then irradiated by protons in C30 cyclotron for about 2-4 h. The initial proton energy was 16.5 MeV, and the proton beam was decayed by a proton beam degrader loaded with carbon films of varying thicknesses. The secondary beam of suitable proton energy irradiated the target. The irradiated yttrium foil was moved into the target dissolution tank, the stages of target dissolution, separation and purification were executed sequentially through an automatic separation apparatus loaded hydroxamic acid resin. Finally, the 89Zr solution was collected and tested for the radionuclide purity, radiochemical purity and element impurity contents respectively. In coin target verification, the direct-cooling coin target shows better thermal conduction properties and the yttrium foil remains intact with a nearly perfect beam shape after bombardment. It proves that the direct-cooling coin target has the ability to withstand long-term beam bombardment and satisfies the production prerequisites for 89Zr. A preferred range of beam energy is determined by irradiation experiments. The beam energy could be controlled within 14.5-12.4 MeV by using 0.3-0.6 mm carbon films. By this means, the radioactive impurities such as 88Zr and 88Y decrease significantly and the radionuclide purity of 89Zr is higher than 99.9%. A stable, automated process for the separation and purification of 89Zr is achieved by separation experiments. These test results show that the production capacity of 89Zr could reach 5 GBq. The radiochemical purity of 89Zr is higher than 97%. While the contents of main element impurities are all less than 2.5 μg/GBq. In this study, the 89Zr production technology is stable and reliable. 89Zr nuclide is successfully produced by the coin target system and automatic separation device. These systems have the potential to expand the production of numerous radionuclide. The large-scale supply of 89Zr is realized for the research and development of 89Zr labelled radiopharmaceuticals in China.

Keywords

• 89zr
• 89y solid target
• proton cyclotron
• nuclide production