ALTERATIONS IN THE BACTERIAL MEMBRANE INTEGRITY INDUCED BY EU-Cl-OFLO ENHANCE THE BACTERICIDAL ACTION OF OFLOXACIN

ROMERO, VERÓNICA L; PONDS, PATRICIA; BOCCO, JOSÉ LUIS; MANZO, RUBEN H.; ALOVERO, FABIANA L.

Rosario, Santa Fe

Congreso; 41° Reunión Anual de Sociedad Argentina de Farmacología Experimental (SAFE),; 2009

SOCIEDAD ARGENTINA DE FARMACOLOGÍA EXPERIMENTAL

The search for new more effective Fluoroquinolones is a constant challenge to overcome the resistance issue. The development of new delivery systems is an alternative tool to preserve the utility of old antimicrobials. Eudragit E100 (Eu) is a cationic polyelectrolyte able to react with the acidic group of drugs. Complexes Eu with Ofloxacin (OFLO) and other counterion, Cl-, which turns the complexes water soluble were prepared, giving clear dispersions (Eu-Cl50-OFLO20) with positive electrokinetic potential and pHs 6.4-6.5. The killing rate and bactericidal action exhibited by OFLO against P.aeruginosa is enhanced in Eu-Cl50-OFLO20. The bacteria were processed for electron microscopy. Those treated with Eu-Cl50-OFLO20 showed damage of bacterial envelope and the cytoplasm was less electrondense. Flow citometry with nucleic acid-binding fluorescent probes show lost membrane integrity. This additional mechanism of action coupled with the own of the FQ could explain the enhancement of the bactericidal action.