Laser ablation mediated ZnO nanoparticles inhibit growth and biofilm forming potential of urinary tract bacterium Proteus mirabilis

Abstract

Abstract Zinc oxide (ZnO) nanoparticles (NPs) were formed via the laser ablation technique of a zinc (Zn) target immersed in deionised water (DIW). The optical, structural, and morphological features of these ZnO NPs were investigated using UV/Vis spectrophotometry, x-ray diffraction, scanning electron microscopy, transmission electron microscopy, and Fourier transforms infrared spectroscopy. XRD results of zinc oxide nanoparticles showed diffraction peaks at 32°, 34.5°, 36.5°, 57°, and 67° corresponding to the (100), (002), (101), (110) and (103). The average nanoparticle size was 21 nm. The TEM images of zinc oxide nanoparticles show that they are spherical in shape and have a size distribution of 20–70 nm. The antibacterial activity of the ZnO NPs was determined and compared with Ciprofloxacin against Proteus mirabilis isolates. The ZnO NPs have significant antibacterial activity against P. mirabilis isolates compared with the control (P ≤ 0.05), and the antibiofilm activity of ZnO NPs was sturdier than that of Ciprofloxacin (P ≤ 0.05). In addition, zinc oxide NPs were more effective than Ciprofloxacin in terms of preventing biofilm formation in the urinary catheter. This finding was confirmed by using atomic force microscopy to investigate the effect of ZnO NPs on bacterial biofilm formation in Foleys catheter (AFM). Therefore, ZnO NPs could be used as a preservative for Foleys catheter by preventing the formation of microbial biofilms. DPPH assay was used to investigate the radical scavenging potential of ZnO NPs.