Why are some isotopes used in medical applications?

Some isotopes are chosen for medical applications primarily because of their specific decay properties, which allow for targeted treatment or imaging. Isotopes that emit radiation in particular forms—such as gamma rays or beta particles—are useful in medical diagnostics and therapy. For instance, radioactive isotopes can be used in positron emission tomography (PET scans) for imaging, as they emit gamma rays which can be detected by imaging equipment.

Additionally, certain isotopes are utilized in targeted radiation therapy to treat cancer; their decay can effectively kill cancer cells while sparing surrounding healthy tissue. The unique characteristics of these isotopes, including their half-lives and types of radiation emitted, make them well-suited for achieving specific therapeutic outcomes or informative imaging results in a medical setting.

Other factors, such as abundance, cost, and atmospheric availability, while potentially influential in isotope selection, are not the primary focus for their use in medical applications. It's the decay properties that specifically align with medical needs that are paramount.