Specific activity

{
  "id": "MLC-T-CHM-011097",
  "term": "Specific activity",
  "field": "Chemistry",
  "definitions": [
    "The activity of a radionuclide per unit mass of an element, or per unit mass of a chemical compound containing the element. This quantity measures the radioactivity concentration relative to the substance itself, not just its volume or total mass. Specific activity is expressed in units of becquerels per kilogram (Bq/kg) or curies per gram (Ci/g), and it is a key parameter in radiotracer studies and the production of radiopharmaceuticals.",
    "(radionuclide) The activity of a given radionuclide per unit mass of that same radionuclide, representing the theoretical maximum specific activity. This value is an intrinsic property of the radionuclide, determined by its decay constant or half-life, and is independent of the chemical form or isotopic abundance. It is calculated as the Avogadro constant times the decay constant, divided by the molar mass, and is expressed in units such as becquerels per gram (Bq/g)."
  ],
  "subject": "Analytical Chemistry",
  "see_also": [
    "activity",
    "isotopes"
  ],
  "references": [
    "PAC, 1994, 66, 2513. 'Nomenclature for radioanalytical chemistry (IUPAC Recommendations 1994)' on page 2515 (https://doi.org/10.1351/pac199466122513)",
    "PAC, 1996, 68, 957. 'Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)' on page 993 (https://doi.org/10.1351/pac199668040957)",
    "PAC, 2021, 93, 69. 'Vocabulary of radioanalytical methods (IUPAC Recommendations 2020)' on page 103 (https://doi.org/10.1515/pac-2019-0302)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/specific-activity/"
}