New approach to production of antimicrobial Al2O3-Ag nanocomposites by electrical explosion of two wires

Abstract Antibacterial Al 2 O 3 -Ag nanoparticles (54 to 69 nm on average) were produced by electrical explosion of wires (EEW) in an oxygen-containing atmosphere. Silver content was varied from 23 to 74 wt% by changing the relative diameters of the Al and Ag wires. For the lowest Ag content, silver clusters less than 10 nm in size were uniformly dispersed on the surface of Al 2 O 3 particles. Al 2 O 3 -Ag nanoparticles of all the compositions carried a positive surface charge at the physiological pH = 7, as determined by zeta potential measurements. The antibacterial properties of Al 2 O 3 -Ag nanoparticles against both Gram-positive and Gram-negative bacteria were studied by the killing kinetics and well diffusion tests. The study revealed higher efficiency of the positively charged Al 2 O 3 -Ag nanoparticles against microorganisms compared to the negatively charged Ag nanoparticles produced by the same electrical explosion procedure.