Journal of Radioanalytical and Nuclear Chemistry

, Volume 308, Issue 3, pp 1081–1088 | Cite as

Radiolabeling, biological evaluation and molecular docking of delafloxacin: a novel methicillin-resistant Staphylococcus aureus infection radiotracer

  • O. A. El-kawy
  • A. S. Abdel-Razek
  • M. S. Sayed


Labeling of delafloxacin with technetium-99m (99mTc) and its characterization in terms of in vitro stability and in vitro binding with methicillin-resistant Staphylococcus aureus (MRSA) were explored. Optimum amounts of reactants were 2.5 mg delafloxacin, 125 µg stannous chloride dihydrate and ~125 MBq pertechnetate. The 99mTc-delafloxacin was stable up to 6 h. Molecular modeling and docking studies showed that the complex will stabilize the DNA-topoisomerase IIA cleavage complex and inhibit strands separation. The in vivo evaluation showed highest specific accumulation in the live MRSA model (8 %) compared to other models. All gathered data supported the usefulness of 99mTc-delafloxacin as a MRSA radiotracer.


Delafloxacin Technetium-99m Methicillin-resistant Staphylococcus aureus infection Septic inflammation Molecular modeling and docking 


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2015

Authors and Affiliations

  • O. A. El-kawy
    • 1
  • A. S. Abdel-Razek
    • 1
  • M. S. Sayed
    • 1
  1. 1.Atomic Energy AuthorityCairoEgypt

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