Blood cell labeling with technetium-99m, 1

A method for labeling red blood cells (RBC) in vitro with sup(99m)Tc by using CIS kit for sup(99m)Tc RBC label is described. Two ml of whole blood are incubated with 0.3 μg of stannous pyrophosphate (0.5 ml of kit solution), followed by removing the supernatant and incubation of sup(99m)Tc to red cells for 5 to 10 minutes. After washing of two times, labeling yield of 91.7 +- 7.0% was obtained in 79 samples. Labeling is better at 370C than in room temperature, and maximum labeling occurs after 5 to 10 minutes incubation with sup(99m)Tc. No dependence on hematocrit of each sample or volume of sup(99m)Tc added was seen. No elution of sup(99m)Tc from red cell was shown by repeated washes of the labeled cells and 10 to 20% radioactivity to initial counts was lost in ACD, saline and plasma 24 hours after incubation in room temperature. It was discussed that sup(99m)Tc RBC kit could be used not only for spleen scan and angiography by sup(99m)Tc-labeled RBC, but for white blood cell and platelet label by sup(99m)Tc. (auth.)