Efficient preparation of high-quality Cu for routine use.

INTRODUCTION

Copper-64 is an attractive radionuclide for positron emission tomography and is emerging as a radiotherapeutic agent. The demand of Cu with low metallic impurities has increased because of its wide applications when incorporated with antibodies, peptides, and proteins. In this study, we propose a new separation method to produce high-quality Cu using a cation exchange column, as well as an automated separation system suitable for large-scale production.

METHODS

Cu was produced from an electrodeposited Ni target via the Ni(p,n)-reaction with a 24MeV HH+ beam at 10eμA (electrical microampere) conducted for 1-3h. The irradiated target was transported to a hot cell and disassembled remotely. Cu was separated by a solvent mixture of HCl and acetone on a cation-exchange resin, AG50W-X8. The chemical purity of Cu final product was evaluated using ion-chromatography coupled with a UV detector and inductively coupled plasma mass spectroscopy for quality as well as metallic impurities.

RESULTS

We obtained Cu in dried form at a yield of 5.2-13GBq at the end of separation, or 521±12MBq/eμAh as the final product within 2.5h of processing time. The metallic impurities were a satisfactory low level in the order of ppb. Major contaminants of Co and Ni were lower than those samples obtained by a widely accepted separation using an anion-exchange resin.

CONCLUSION

Using a cation-exchange resin and a systematic operation, we successfully reduced the contamination level of the Cu product. As a straightforward separation method, which shortened the entire processing time, we obtained a satisfactory amount of high-quality Cu available for routine use.