The biodistribution and kinetics of the Samarium-153 labeled avidin, streptavidin and biotin

摘要

Objective: To label avidin (Av) or streptavidin (SA) with ~153Sm by taking advantage of the high binding affin- ity of biotin to Av or SA. Methods: A biotin derivative (DTPA-biotin) was radiolabelled with ~153Sm and then bound to Av or SA. The in vivo kinetics and biodistribution of ~153Sm-labeled Av, SA and DTPA-biotin were studied in rats and mice. Results: ~153Sm-Av was characterized by rapid clearance from the blood with high liver and renal uptake; ~153Sm-SA was Cleared from the blood slowly with high retention in the liver, spleen and kidney, whereas ~153Sm-DTPA-biotin metabolism was Accelerated, and its excretion was mainly through the kidney.