strontium-89

Strontium-89 () is a radioactive isotope of strontium with a half-life of 50.56 days. It undergoes β− decay (with practically no gamma rays) into yttrium-89. Strontium-89 has application in medicine. It is also a fission product, but is produced technically by neutron capture on ordinary strontium.

== History == Strontium-89 was first synthesized in 1937 by D. W. Stewart et al. at the University of Michigan; it was synthesized via irradiation of stable strontium (the 88Sr isotope) with deuterons. Biological properties and applications of strontium-89 were studied for the first time by Belgian scientist Charles Pecher. Pecher filed a patent in May 1941 for the synthesis of strontium-89 and yttrium-86 using cyclotrons, and described the therapeutic use of strontium.