Highly efficient antibacterial activity of graphene/chitosan/magnetite nanocomposites against ESBL-producing Pseudomonas aeruginosa and Klebsiella pneumoniae

Abstract

In the present study, chitosan-containing nanocomposites were investigated as new antibacterial agents. Magnetite (Fe₃O₄) nanoparticles (NPs) as well as chitosan (CS)/Fe₃O₄ nanocomposites (NCs) and graphene(Gr)/CS/Fe₃O₄ NCs were synthesized by simple hydrothermal method. Their composition, structure and morphology were studied, followed by the evaluation of their antibacterial activity against ESBL-producing and gram-negative P. aeruginosa and K. pneumoniae bacterial strains. The Gr/CS/Fe₃O₄ NCs showed significantly higher antibacterial activity compared to Fe₃O₄ NPs and CS/Fe₃O₄ NCs (105 and 69 % higher against P. aeruginosa as well as 91 and 77 % higher against K. pneumoniae, respectively). The minimum inhibitory concentration (MIC) of Gr/CS/Fe₃O₄ NCs against P. aeruginosa and K. pneumoniae were 60 and 70 μg/mL, respectively. The synergistic antibacterial activity and facile synthesis of Gr/CS/Fe₃O₄ NCs suggests their applicability as novel highly efficient antibacterial agents with potential for a wide range of biomedical applications, where antibacterial properties are needed.

Keywords: Antibacterial activity; Chitosan; Graphene; Hydrothermal synthesis; Magnetite; Nanocomposites.