Automation of nuclear chemistry processes leads to more efficient production of astatine for cancer therapy

In research, published in Chemical Engineering Journal, scientists design and test an automated device aimed at remote dissolution of an irradiated bismuth target followed by extraction chromatography column separation of Astatine-211 (At-211) from unwanted impurities for producing At-211.

At-211 is one of a handful of promising alpha-emitting radioisotopes for cancer therapy. Its short 7.2-hour half-life means that it must be handled quickly to minimize losses due to radioactive decay.

The automated device can use as many as 10 independent columns, allowing it to divide the At-211 production activity. It minimizes the dose of radioactivity to workers producing the At-211 and reduces the time needed to prepare samples for shipment to less than 20 minutes.

For convenience, each column containing At-211 can be shipped to the desired destination facilities. This allows researchers to implement their own chemical protocols. The time required for complete target dissolution and At-211 purification is as long as 20 minutes with a very high 95% elution yield.

The fast and efficient new chemical At-211 production procedure is the result of using the principles of process automation, which helps to simplify and accelerate routine production of this valuable radioisotope.

The approach fully automates all chemical processing steps, resulting in minimized dose to personnel and high reproducibility. This compact device can significantly increase availability of the promising At-211 radioisotope for research centers, hospitals, and patients.

The emission of alpha particles near tumor cells is a promising tactic in cancer treatment. These particles damage a tumor while causing only limited damage to surrounding cells. In comparison, beta particles travel much farther and so, cause more damage beyond the targeted cells. At-211 is one of nine alpha-emitting radioisotopes that researchers have clinically studied.

At-211 (7.2-hour half-life) has limited availability worldwide. For example, there are only five centers in the United States capable of its production. This radioisotope is available through the Department of Energy Isotope Program.

The Texas A&M K150 cyclotron is capable of routine production of medically relevant quantities of At-211 and can deliver it to nearby facilities using overnight shipment options. The facility is part of the DOE Isotope Program University Isotope Network.

More information:
Evgeny E. Tereshatov et al, Compact automated apparatus for rapid astatine recovery from nitric acid media: Design, application, and impurity characterization, Chemical Engineering Journal (2022). DOI: 10.1016/j.cej.2022.136176

Provided by US Department of Energy