Synthesis of zirconia nanoparticles using Laurus nobilis for use as an antimicrobial agent.

The green biogenic synthesis of nanoparticles using natural sources is always eco-friendly and attractive. The current study has focused on the production of ZrO₂ nanoparticles using the aqueous leaf extract of Laurus nobilis (bay leaf). The structural and morphological properties of ZrO₂ nanoparticles were investigated through UV–visible absorption spectrophotometer, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM) and dynamic light scattering (DLS). The characterization techniques confirmed the formation of ZrO₂ nanoparticles with the diameter from 20 to 100 nm. FTIR spectra also demonstrated the formation of ZrO₂ in the crystalline phase. The narrow and edged peaks obtained from XRD symbolized a notable increase in the crystalline index of the obtained zirconium nanoparticles. The SEM micrographs revealed the morphology as spherical shaped. Various concentrations of the obtained zirconium nanoparticles were tested to check their inhibitory action against certain microorganisms such as Gram-positive bacteria, Gram-negative bacteria and a fungus. The inhibitory actions against the tested microorganisms were directly proportional to the concentration of the obtained zirconium nanoparticles. Consequently, the dispersion properties of ZrO₂ nanoparticles in the aqueous solution increased considerably, which might have contributed to the antimicrobial activity. Hence, the synthesized ZrO₂ nanoparticles of L. nobilis can serve as an antimicrobial agent, which may play a vital role in medical industry. [ABSTRACT FROM AUTHOR]