Preparation and Biodistribution of ~(131)I Labeled 3-Amino-1-Hydroxypropylidene-1,1-Bisphosphonate

3-amino-1-hydroxypropylidene-1,1-bisphosphonate (ABP) was synthesized and labeled with 131I using N-succinimidyl5-(tri-butylstannyl)-3-pyridinecarboxylate(SPC) as a bi-functional linker.131I could be coupled to ABP via a 131I-SIPC intermediate with a labeling yield of more than 64%,and a radiochemical purity of more than 99% after HPLC purification.After 72 h at room temperature,the radiochemical purity was still more than 98.8%,implying that the 131I-SIPC-ABP is stable in vitro.Biodistribution experiments in mice show that 131I-SIPCABP has high affinity to bone and high stability in vivo as well as in vitro.