After a single administration, radiolabeled compounds can be used to follow pharmacokinetics and biodistribution profile for several days in the same animal with SPECT/CT. In addition to SPECT/CT, tissue gamma counter analysis can be added in all studies for a more complete biodistribution profile.
Radiolabeled molecules used for PK/biodistribution studies and autoradiography in mice and rats include commercial pre-labeled (3H,14C) and in-house labeled (125I, 123I, 99Tc, 111In) molecules, particles or cells.