Iodine-124 as a label for pharmacological PET imaging

With the growing number of biotechnology products and drug delivery systems entering preclinical and clinical studies, pharmacological imaging studies with PET play an increasingly significant role. Such studies often require investigation of slow and complex pharmacokinetics (PK). This suggests labeling of the drug candidate with radionuclides that have long physical half-lives. Among the currently available PET positron emitters, 124I has the longest physical half-life (4.2 days). This, combined with the well-investigated behavior of iodine in vivo, makes 124I very attractive for pharmacological studies. However, the high energy of the positrons emitted by 124I and the presence of single photons in the 124I emission can potentially introduce limitations in the quantitative analysis of the images. The objective of this research was to determine whether the use of 124I as a PET label provides data quality suitable for PK studies. The study was carried out using MicroPET P4 scanner (Siemens/Concorde Micros...