The Tcm labeled zoledronate (99Tcm-ZL) was prepared by the reduction of Na99TcmO4 with SnCl2 2H2O. 99 ˙ The effect of the amounts of SnCl2 2H2O and ZL

and pH value on the labeling yield and radiochemical purity of ˙ 99Tcm-ZL were investigated. When the amounts of SnCl2 2H2O and ZL were more than 40 μg and 2mg

respectively

˙ the pH value was between 3 and 9

and the labeling reaction continued for 8min at room temperature

both labeling yield and radiochemical purity of Tcm-ZL were over 90%. The biodistribution in mice and bone scan in rabbit of 99 99Tcm-ZL were also studied. The results show that at 30min after injection of Tcm-ZL

the uptake in bone was up to 99 13.45%ID/g

bone-to-muscle and bone-to-blood uptake ratios were 28.01 and 16.96

respectively. The clear bone-imaging was obtained at 75min after injection of Tcm-ZL. So Tcm-ZL was a potential bone-imaging agent. 99 99