Modifying effect of commercially available stannous pyrophosphate (PYRO-Sn) on the tissue affinity of 99mTc...

Investigations were performed to examine the conditions required for in vivo labelling of red blood cells (RBCs) with 99mTc after injection of stannous pyrophosphate. It was found that good in vivo labelling of RBCs is possible and that the efficacy of this procedure is high. The highest concentration of 99mTc in the blood occurred in the first 2 h after pertechnetate injection, and the optimum time between stannous pyrophosphate and pertechnetate injection ranged from 10 to 30 min.