Interactions of a non-fluorescent fluoroquinolone with biological membrane models: A multi-technique approach

• Type: Article in International Scientific Journal
• Date: 2015

Authors

Sousa, CF (Author) Other; Ferreira, M (Author) Other; Abreu, B (Author) Other; Medforth, CJ (Author) Other; Paula Gameiro (Author) FCUP

Journal

Title: International Journal of Pharmaceutics

Vol. 495

Pages: 761-770

ISSN: 0378-5173

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 11 Citations

Scopus - 11 Citations

Other information

Authenticus ID: P-00G-Q39

DOI: 10.1016/j.ijpharm.2015.09.037

Abstract (EN): Fluoroquinolones are antibiotics which act by penetrating into bacterial cells and inhibiting enzymes related to DNA replication, and metal complexes of these drugs have recently been investigated as one approach to counteracting bacterial resistance. In this work, we apply a multi-technique approach to studying the partition coefficient (K-p) for the non-fluorescent third-generation fluoroquinolone sparfloxacin or its copper-complex with lipid membrane models of Gram-negative bacteria. The techniques investigated are UV-vis absorption and F-19 NMR spectroscopies together with quenching of a fluorescent probe present in the lipids (using steady-state and time-resolved methods). F-19 NMR spectroscopy has previously been used to determine the K-p values of fluorinated drugs but in the case of sparfloxacin did not yield useful data. However, similar K-p values for sparfloxacin or its copper-complex were obtained for the absorption and fluorescence quenching methods confirming the usefulness of a multi-technique approach. The K-p values measured for sparfloxacin were significantly higher than those found for other fluoroquinolones. In addition, similar K-p values were found for sparfloxacin and copper-complex suggesting that in contrast to other fluoroquinolones hydrophobic diffusion occurs readily for both of these molecules.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10