ABSTRACT

Biofilm forming multidrug resistant bacteria has become a threat to therapy. In this work we aim to potentiate first line antibiotics by the synergistic combination with cerium oxide nanoparticles. Bacterial specimens collected from burn wounds and urinary catheters are diagnosed by culturing and biochemical tests. CeO2 NPs are analyzed for fcc structure and nanoparticles size by X-Ray diffraction. Antibacterial activity and inhibition against bacterial isolates for CeO2 NPs and respective antibiotics are tested by agar diffusion method and checkerboard assay. In the synergistic combination of CeO2 NPs with Ciprofloxacin, Levofloxacin and Rifampicin against Proteus mirabilis, Escherichia coli and Staphylococcus aureus the minimum inhibitory concentrations for the three antibiotics are reduced by 16- fold from their individual MIC and their inhibition are raised to the edge of 90 %. Above a concentration of 24 μg/ml Ciprofloxacin, Levofloxacin and Rifampicin showed additive interaction judging from their fractional inhibitory concentration values. The study demonstrates the efficacy of cerium oxide nanoparticles in potentiating the antibiotic mechanism of interaction to circumvent bacterial resistance.

Keywords: wounds, urinary catheter, synergy, cerium oxide, antibiotic