New Technique Simplifies Production of Medical Copper-64 Isotope

A groundbreaking method for producing the medical isotope Copper-64 has been developed at the Vienna University of Technology (TU Wien), significantly reducing costs and complexities associated with its manufacture. Traditionally, Copper-64, which is critical for imaging in medical applications and holds promise for cancer treatment, has been produced by bombarding nickel atoms with protons—a process that is not only intricate but also expensive.

Until now, the conventional approach involved using nickel-64, which, when bombarded, transforms into Copper-64 by ejecting a neutron. This method requires access to a cyclotron and enriched nickel-64, both of which are costly and not readily available. The new technique, described in the journal Dalton Transactions, shifts the focus from nickel to Copper-63, which is more abundant.

Innovative Recoil Chemistry

The new approach utilizes a process known as recoil chemistry, where Copper-63 is irradiated with neutrons in a research reactor to convert it directly into Copper-64. This method effectively adds a neutron to Copper-63, resulting in Copper-64. However, a significant challenge arose: the newly formed Copper-64 nuclei could not be separated chemically from the abundant Copper-63 atoms.

According to Veronika Rosecker from TU Wien, this issue has been addressed by incorporating the copper atoms into specially designed molecules prior to irradiation. When a Copper-63 atom becomes Copper-64, it emits gamma radiation, which generates an energy recoil that ejects the Copper-64 from the molecule. This clever approach allows for a clean separation of the isotopes, facilitating efficient extraction of Copper-64 for medical use.

Finding the Right Molecular Structure

The success of this method hinged on identifying a suitable molecule that could endure the conditions within a nuclear reactor while remaining soluble for subsequent chemical processing. Martin Pressler noted that researchers developed a metal-organic complex similar to heme, the molecule found in human blood. This complex was chemically modified to enhance its solubility, enabling straightforward recovery of Copper-64 following neutron irradiation.

The new method presents several advantages: it can be automated, the molecules can be reused without degradation, and it eliminates the need for a cyclotron, making the production of Copper-64 more accessible. This innovation could lead to lower costs in medical imaging and enhance the availability of Copper-64 for clinical applications.

By simplifying the production process, this research not only paves the way for more cost-effective medical imaging solutions but also positions Copper-64 as a vital tool in cancer therapy. The findings from TU Wien underscore the potential of applying advanced chemical techniques in the field of medical isotope production, promising significant advancements in patient care.

For further details, refer to the article published by Martin Pressler et al. in Dalton Transactions, DOI: 10.1039/d5dt02046h.