Study on the preparation and biodistribution of 99mTc-HMIBP

99mTc-HMIBP, a new bone-imaging agent, was prepared by the reduction of 99mTc-pertechnetate in the presence of SnCl2·2H2O. The effects of the amounts of SnCl2·2H2O and HMIBP and the pH value on the labeling yield and radiochemical purity of 99mTc-HMIBP were investigated. When the amounts of SnCl2·2H2O and HMIBP were more than 10 μg and 2.5 mg, respectively, the pH value was between 2 and 7, and the labeling reaction continued for 10 min, both labeling yield and radiochemical purity of 99mTc-HMIBP were more than 90%. The biodistribution in rats and bone scan in rabbits were also studied. The results showed that the bone uptake is up to 7.94%ID/g at 30 min after injection of 99mTc-HMIBP, bone-to-muscle and bone-to-blood uptake ratios were 20.89 and 16.89, respectively. The clear bone image was obtained at 120 min after injection of 99mTc-HMIBP and clearance in soft tissue was visible. All of the above-mentioned results suggested that 99mTc-HMIBP may be a potential bone-imaging agent.