New amino bisphosphonate compound for skeletal imaging: Comparison study with methylenediphosphonic acid (MDP) and (1-hydroxyethane-1,1-diyl) diphosphonic acid (HEDP)

A novel bisphosphonate derivative (1-aminoethane-1,1-diyl)diphosphonic acid (AEDP) has been prepared and successfully labeled with ^99mTc at high labeling yields. The in vivo biodistribution of ^99mTc-AEDP has been investigated and compared with two reference compounds Tc-99m methylene diphosphonate (^99mTc-MDP) and Tc-99m (1-hydroxyethylidene) diphosphonate (^99mTc-HEDP). The biodistribution studies have demonstrated a high uptake of the radiotracer ^99mTc-AEDP in the bone and a rapid clearance from the blood (such as the two technetium-labeled bone imaging agents in current use: ^99mTc-MDP and ^99mTc-HEDP). Additionally, the scintigraphic images of ^99mTc-AEDP in normal rats have revealed high selective skeletal uptake.