BINDING OF TRACE AMOUNTS OF IONIC INDIUM-113M TO PLASMA TRANSFERRIN

When indium-113m was injected intravenously in ionic form for blood pool scanning, it was bound to plasma transferrin. In vitro studies utilizing starch gel electrophoresis and immunoelectrophoresis showed that trace amounts of indium were bound almost entirely to the transferrin; iron-59 labeled plasma was used for comparison. Starch gel electrophoresis and gel filtration were carried out with plasma samples containing increasing amounts of indium. It appeared that approximately 4 μg of indium per ml of normal human plasma saturated the transferrin and the excess indium above this level was bound mainly to α2-globulins. © 1968.