Commercially available Ag100, Ag20-30, ZnO, Cu and SiO2 nanoparticles were used in the practical part of the master’s thesis. We studied the antibacterial effects of metal nanoparticles and released ions. The shape of the nanoparticles was characterized by transmission electron microscopy (TEM). The effect of ions and nanoparticles on bacteria Escherichia coli in Staphylococcus aureus was determined by spectroscopic measurements of optical density (OD600) and colony forming unit method (CFU). The effect of ions on humane cells was determined by cytotoxic test and the exact concentration of ions released from nanoparticles was determined by inductively coupled mass spectroscopy (ICP-MS). The effect of metal nanoparticles on morphology of bacterial cells in biofilms was examined by scanning electron microscopy (SEM). Minimal inhibitory concentration (MIC) of Ag20-30 ions is between 0,64 and 0,85 µg/mL, for E. coli. MICs of Ag20-30 and Cu ions are 0,85 and 265 µg/mL, for S. aureus. Despite antimicrobial efficacy of metal ions, the use is limited because they have cytotoxic effect on mouse fibroblast cells, except SiO2 ions. MIC of Ag100 NPs is between 3,75 and 7,5 mg/mL, MIC of Ag20-30 NPs is between 1 and 3,75 mg/mL, MICs of Cu and ZnO NPs are 3,75 mg/mL and MIC of SiO2 NPs is 7,5 mg/mL, for E. coli. MICs of Ag100, Ag20-30 and ZnO NPs are 3,75 mg/mL, MIC of Cu NPs is 1 mg/mL and MIC of SiO2 NPs is 7,5 mg/mL, for S. aureus. The results prove the antibacterial effects of ions and nanoparticles on bacteria S. aureus and E. coli.
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