Abstract

Background: Levofloxacin is a potent antibiotic with severe side effects due to its high doses. Bacterial resistance may be due to frequent use of antibiotics. Biogenic gold nanoparticles conjugated levofloxacin (Au-HSA-LvN-NPs) were developed by Human Serum Albumin (HSA) and nitrate reductasemediated pathways.

Methods: Au-HSA-LvN-NPs (size = 27.2 ± 1 nm) were readily generated with high emulsion stability zeta potential (-13.3 mV). The developed nanoparticles were also characterized by UVvisible spectroscopy, Transmission Electron Microscopy and Dynamic Light Scattering techniques.

Results: The optimized nanoparticles were found efficient against both Gram-positive bacteria and Gramnegative bacteria specifically S. aureus (MIC-0.373 µg/ml), E. coli (MIC-0.149 µg/ml) and P. aeruginosa (MIC-0.346 µg/ml) respectively.

Conclusion: The efficiency of bioconjugated levofloxacin got improved by 1.94 times, 2.89 times and 1.46 times against S. aureus, E. coli and P. aeruginosa respectively, in comparison to pure levofloxacin.

Keywords: Gold nanoparticles, human serum albumin, levofloxacin, nitrate reductase, zeta potential, antibiotics.

Graphical Abstract