Binding of 99mTc(113Sn)-MDP to human serum albumin. The influence of various technetium, tin, and MDP concentrations

Abstract The HSA-binding of 99m Tc incubated as 99m Tc( 113 Sn)-MDP depends in vitro on the presence of competing anions normally present in plasma and on the MDP and Tc concentration, but is independent of the Sn concentration. The HSA-binding of 113 Sn depends on the MDP and Sn concentration; not on the Tc concentration. 99m Tc(Sn)-MDP binds to HSA as a unit. The binding of 99m Tc(Sn)-MDP to plasma proteins in vivo is much lower as calculated from in vitro experiments because of competition between 99m Tc(Sn)-MDP and endogenous anions for the same binding-sites.