Preparation, biodistribution, and small animal PET of 45Ti-transferrin.

Abstract

45Ti forms a complex with apotransferrin that remains intact in vivo. Results of the biodistribution in mice showed that the tumor had increased uptake compared with nontarget organs (e.g., muscle). The microPET images of tumor-bearing mice clearly delineate the tumors from the surrounding tissue. Comparison of the data suggests that tissue uptake is similar whether injecting 45Ti-transferrin directly or as 45Ti-citrate, which transchelates to transferrin before the time of imaging.