Preparation and investigation of gold nanoparticles by the technique of laser ablation for biological application

Abstract

This paper utilises environmentally friendly and cost-effective methods for the synthesis of gold nanoparticles (AuNPs) using distilled water (DW) solution via liquid pulse laser ablation (PLAL) technique with wavelength (1064nm) and different laser energies. The properties of Au NPs were studied by using absorption spectrometry and its particle shape, surface morphology and size ratio were analysed by transmission electron microscopy (TEM) and X-ray diffraction. The prepared samples were examined by X-ray diffraction (XRD) and the analyses showed the formation of a crystal structure for gold (Fcc) and showed an improvement in the crystal level by increasing the energy of the laser beam, which leads to an increase in the grain size. The Uv_Vis results showed the formation of Au NPs through the appearance of the surface plasmon resonance (SPR) peak located at 523nm within the UV visible spectrum. Transmission electron microscopy (TEM) images showed Au NPs in a spherical or aspherical cluster shape with diameters ranging from 25 to 50 nm. Au NPs act as antibacterial against Staph aureus, and p.aeruginosa. This is due to the large surface-to-volume ratio which provides a more effective means of enhancing bacterial activity as measured by the area of inhibition.