Synthesis and evaluation of ciprofloxacin-nitroxide conjugates as anti-biofilm agents

Verderosa, Anthony, Mansour, Sarah C., de la Fuente-Núñez, César, Hancock, Robert E.W., & Fairfull-Smith, Kathryn E. (2016) Synthesis and evaluation of ciprofloxacin-nitroxide conjugates as anti-biofilm agents. Molecules, 21(7), Article Number-841.

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As bacterial biofilms are often refractory to conventional antimicrobials, the need for alternative and/or novel strategies for the treatment of biofilm related infections has become of paramount importance. Herein, we report the synthesis of novel hybrid molecules comprised of two different hindered nitroxides linked to the piperazinyl secondary amine of ciprofloxacin via a tertiary amine linker achieved utilising reductive amination. The corresponding methoxyamine derivatives were prepared alongside their radical-containing counterparts as controls. Subsequent biological evaluation of the hybrid compounds on preformed P. aeruginosa flow cell biofilms divulged significant dispersal and eradication abilities for ciprofloxacin-nitroxide hybrid compound 10 (up to 95% eradication of mature biofilms at 40 μM). Importantly, these hybrids represent the first dual-action antimicrobial-nitroxide agents, which harness the dispersal properties of the nitroxide moiety to circumvent the well-known resistance of biofilms to treatment with antimicrobial agents.

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2 citations in Scopus
1 citations in Web of Science®
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ID Code: 96374
Item Type: Journal Article
Refereed: Yes
DOI: 10.3390/molecules21070841
ISSN: 1420-3049
Divisions: Current > QUT Faculties and Divisions > Science & Engineering Faculty
Copyright Owner: 2016 by the authors; licensee MDPI, Basel, Switzerland.
Copyright Statement: This article is an open access
article distributed under the terms and conditions of the Creative Commons Attribution
(CC-BY) license (
Deposited On: 28 Jun 2016 23:48
Last Modified: 28 Jun 2017 00:01

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