In vitro technetium-99m red blood cell labeling using commercial stannous pyrophosphate

A simple and rapid technique of preparing technetium-99m-labeled erythrocytes using commercial stannous pyrophosphate as the reducing agent was developed. The technique involves incubating red cells with stannous pyrophosphate, centrifugation, and addition of Tc-99m pertechnetate to the red cell fraction. A mean red cell labeling efficiency of 94% was achieved in 10 patient samples and less than 5% in vitro dissolution of Tc-99m red blood cells occurred up to two hours after preparation.