Milling Effect on the Structural and Antibacterial Properties of ZnO and CuO Nanoparticles.

In this work, ZnO and CuO nanocrystalline powders were prepared by method of high-energy ball milling. The milling process was performed at 450 rpm speed for 5, 10, 15, and 20 h periods of time. Structural and morphological properties of the powders were investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. Results confirmed the formation of single-phase nanocrystalline structure from micron-scale (as-received) material. The samples were tested for antibacterial activity against Gram-positive bacteria Bacillus cereus B9 (ATCC 25923), Bacillus licheniformis M30, Bacillus subtilis B1, Micrococcus luteus M3, Staphylococcus aureus (ATCC 6538) and Gram-negative bacteria Escherichia coli (ATCC 25922) and Pseudomonas aeruginosa P7. The antibacterial activity was determined by the disc-diffusion method. [ABSTRACT FROM AUTHOR]