Use
For example, in biodistribution studies, it is common to track the movement of a compound of interest through an animal. To measure the compound it is chemically joined to a radionuclide. Thus the energy measured from the radioactive decay is related to the quantity of the compound of interest.
Samples may be collected and counted at short time intervals (ex: 1 and 4 hours). The next samples (from another set of animals injected at the same starting time) may not be collected and counted until 24, 48, or 72 hours. Because isotopes for therapy and imaging often have a relatively short half-life (under 10 days), it is necessary to adjust the data in order to compare all the time points.
For example, the isotope copper-64, commonly used in medical research, has a half-life of 12.7 hours. If you inject a large group of animals at "time zero", but measure the radioactivity in their organs at two later times, the later groups must be "decay corrected" to adjust for the decay that has occurred between the two time points.
Read more about this topic: Decay Correct
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