Anti-quorum sensing and anti-biofilm activity of nickel oxide nanoparticles against Pseudomonas aeruginosa

Abstract

Nickel oxide nanoparticles (NiO NPs) were prepared by a chemical reduction method. The physical and morphological observations of NiO NPs were assessed by powder X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, and UV–vis diffuse reflectance spectroscopy, scanning electron microscopy and transmission electron microscopy. Furthermore, the in vitro inhibition studies of violacein degradation in Chromobacterium violaceum ATCC 12472 and biofilm eradication in P. aeruginosa were detected at 50 μg/mL and 60 μg/mL, respectively. In addition, the biofilm inhibition was confirmed by ring biofilm degradation and time-kill variation assays. The live/dead cell variations, biofilm architecture damage and cell wall modifications of NiO NPs were investigated using confocal laser scanning microscope and SEM. In addition, NiO NPs were found to act as anti-biofilm agent against P. aeruginosa. Finally the in-vivo toxicity of NiO NPs was investigated against Artemia franciscana, suggesting low toxicity.