Actinium ion (Ac³⁺)

The actinium ion (Ac³⁺) is the triply charged cation of the chemical element actinium. Actinium is a highly radioactive, silvery-white metallic element, the first member of the actinide series, with atomic number 89 and symbol Ac. The most stable and useful form in solution is Ac³⁺, which is colorless and chemically similar to large lanthanide ions like La³⁺. Actinium has no known physiological function and is highly toxic due to its intense radioactivity; if ingested, it accumulates in the liver and bones and can be hazardous. The ion itself is not a receptor, enzyme, transporter, or classical therapeutic target, but certain actinium isotopes (not the ion per se) are used in medicine, particularly actinium-225 for targeted alpha therapy in cancer treatment, often when chelated to biological targeting molecules. Note: “Actinium ion” is not, by itself, a pharmacological or biological receptor/target. The entry is incorrect in the sense that it is a chemical species, not a protein, enzyme, transporter, or therapeutic macromolecule. The actual therapeutic relevance is associated with actinium isotopes, especially as radioisotope payloads, not direct interaction with drugs or biological pathways. Safety concerns center on its radioactivity and potential to cause tissue damage upon exposure.

Other names

Ac ionAc³⁺ ion