Antibacterial properties of silver nanoparticles synthesized via nanosecond pulsed laser ablation in water

Ag nanoparticles were synthesized in pure water by a nanosecond pulsed laser ablation process and characterized using transmission electron microscopy and ultraviolet-visible spectroscopy. The as-synthesized nanoparticles were determined to have an average particle size of 10.17 ± 2.95 nm. Their absorption spectra were consistent with that of Ag nanoparticles produced through chemical methods. The antibacterial properties of Ag nanoparticles at concentrations of 100 and 250 μg/ml were studied against the gram-positive bacterium Staphylococcus aureus at two infectious inocula (103 and 105 CFU/ml). Over a 24-h test period, the samples containing 100 μg/ml exhibited early bacteriostatic activity but did not stop long-term bacterial growth, while the 250 μg/ml samples demonstrated bactericidal and bacteriostatic effects. These results highlight the use of Ag nanoparticles synthesized through laser ablation as green and effective antibacterial agents for biomedical applications.