Y-EDTA was eluted from 90 Sr/ 90 Y generator

labeled activation charcoal. The upper liquid was removed with centrifugation. The labeled yield was over 95%. 90 Y-charcoal was very stable in saline. After i.m or i.p to mice

the over 99% radioactivity were remained in the point of injection after 72h. The uptake of femur is (0.0019±0.0010)%ID/g by i.m

and (0.0453±0.0051)%ID/g after 72h by i.p. The other’s organic activity is nearly background. In conclusion

90 Y-charcoal is stable and doesn’t degraded in vivo. It suggested that 90 Y-charcoal may be a potential agent for internally therapeutic use as other particles like glass-microsphere.