Samarium Sm-153

**Semantic type:** Element, Ion, or Isotope|Indicator, Reagent, or Diagnostic Aid

**Definition:** A beta- and gamma-emitting isotope, with antineoplastic activity. Emitted by samarium Sm 153, beta particles directly damage cellular DNA and, by ionizing intracellular water to produce several types of cytotoxic free radicals and superoxides, indirectly damage intracellular biological macromolecules, resulting in tumor cell death. Samarium Sm 153 also emits gamma-photons that can be detected for external imaging.

**Synonyms:** - 153Sm - SAMARIUM SM-153 - Samarium, Isotope of Mass 153 - Samarium-153 - Samarium-153 - Sm-153 - Sm-153 - samarium 153