Bismuth-213

Bismuth-213 is a radioactive isotope of bismuth. It is an alpha-emitting radionuclide with a half-life of approximately 46 minutes. Bismuth-213 is used in targeted alpha therapy (TAT), a type of radiotherapy that is used to treat certain types of cancer.

Production

Bismuth-213 is produced through the decay of uranium-233. Uranium-233 decays to thorium-229, which then decays to radium-225, actinium-225, and finally to bismuth-213. This decay chain is known as the actinium decay series.

Use in Medicine

In medicine, bismuth-213 is used in targeted alpha therapy (TAT). TAT is a type of radiotherapy that uses alpha-emitting radionuclides to kill cancer cells. The advantage of using alpha-emitting radionuclides like bismuth-213 is that they have a high linear energy transfer (LET), which means they can cause a lot of damage to cancer cells while sparing healthy tissue.

Bismuth-213 is often attached to a molecule that can specifically target cancer cells. This molecule is known as a chelate. The chelate carries the bismuth-213 to the cancer cells, where the alpha particles emitted by the bismuth-213 can kill the cancer cells.

Safety

Like all radioactive substances, bismuth-213 must be handled with care. It emits alpha particles, which can cause damage to living tissue if they are ingested or inhaled. However, because alpha particles have a very short range, they do not pose a risk if they are outside the body.

See Also

• Radiotherapy
• Alpha particle
• Cancer