[en] We describe here the synthesis of ^99mTc-ciprofloxacin by four different methods and its biodistribution. All of the methods gave high radiochemical yields of ≥90% and high stability of ≥90% at 6 h after preparation. However HPLC analysis, bacterial binding assay, and in vivo distribution for the four ^99mTc-ciprofloxacins showed different results. Among these methods, the use of formamidine sulfinic acid with microwave heating (Method A) was fast and easy, and gave more desirable biological properties than the other methods