Mechanochemical synthesis and antibacterial effect of CuBi2O4 nanoparticles against P. aeruginosa and S. aureus

A R Vázquez-Olmos, A Rubiales-Martinez, A Almaguer-Flores, A L Vega-Jiménez and G Prado-Prone

Abstract

Nanoparticles (NPs) of CuBi₂O₄ with an average size around 25 nm were obtained by a novel and eco-friendly synthesis method. X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM) reveal that CuBi₂O₄ NPs possess a tetragonal crystal structure. These NPs were characterised by Raman scattering, ultraviolet-visible (UV-Vis) absorption, photoluminescence (PL), and electron paramagnetic resonance (EPR) spectroscopies. Furthermore, an in vitro study of the antibacterial effect of CuBi₂O₄ NPs against two bacterial strains, Pseudomonas aeruginosa (ATCC 43636) and Staphylococcus aureus (ATCC 25923), was carried out. The results obtained from the counting of colony-forming units (CFUs) and by the XTT-PMS cell viability assay showed an inhibition of the bacterial growth by 88%–87% for P. aeruginosa and 100% for S. aureus, at 50 mg ml⁻¹ of NPs concentration. The results of this work suggest that these nanoparticles have the potential to be used as antibacterial agents by embedding them into different surfaces or being dispersed in a coating, to prevent the bacterial colonisation.