Calibration of activity readings from radiopharmaceuticals with impurities

• Published in: Journal of radioanalytical and nuclear chemistry Vol. 290; no. 1; pp. 153 - 157
• Main Authors: Chang, Kwo-Ping, Chen, Ching-Kuei, Shen, Lie-Hang
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.10.2011
• Subjects: Calibration; Chemistry; Chemistry and Materials Science; Curve fitting; Diagnostic Radiology; Hadrons; Heavy Ions; Impurities; Inorganic Chemistry; Mathematical analysis; Nuclear Chemistry; Nuclear medicine; Nuclear Physics; Photons; Physical Chemistry; Radioactivity; Dose calibrator; Relative response; Apparent radioactivities; Impurities
• ISSN: 0236-5731; 1588-2780
• DOI: 10.1007/s10967-011-1169-9

Accurately determining the amount of a radionuclide actually administered to a patient is an important aspect of quality control in nuclear medicine. In this study, in order to accurately assess the “apparent” radioactivities of radionuclides with impurities by a dose calibrator, two methods, (1) curve fitting, and (2) relative sensitivities calculation, have been employed to determine the parameter, M (relative response). From the comparisons between the measurement and re-calculated radioactivity using the M values, each method was found to have its own advantage and disadvantage, depending upon the fraction ratio of the impurity as well as the energy level of the impurity’s photons. This study might be helpful for improving the assessment of radiopharmaceuticals’ “true” activity and its “apparent” activity measured by a dose calibrator.