Synthesis and biological evaluation of technetium-sarafloxacin complex for infection imaging

Technetium-99m-sarafloxacin was synthesized and formulated for the development of a potential diagnostic imaging agent for the bacterial infection and inflammation with higher efficiency than the commercially available ^99mTc-ciprofloxacin. Factors influencing the labeling yield such as sarafloxacin amount, pH of the labeling reaction, SnCl₂ amount and reaction time were optimized. The labeled drug was subjected to preclinical evaluations in mice. The biodistribution studies indicated that ^99mTc-sarafloxacin displayed relatively high uptake in the infectious lesion (T/NT = 4.2 ± 0.1) at 2 h post-injection. The results revealed that ^99mTc-sarafloxacin cannot discriminate infection from sterile inflammation.