en عمومى General پژوهشي Research <p><strong>Background:</strong> Nowadays, due to the increasing problems of microbial resistance, scientists are searching for the safest and most effective way to fight them. The colloidal silver (Ag) and titanium dioxide (TiO2) nanoparticles can effectively fight against many bacterial microorganisms. Therefore, the purpose of this study was to investigate the antibacterial and cytotoxic properties of Ag and TiO2 nanoparticles, against Shigella dysenteriae and Staphylococcus aureus.<br> <strong>Methods:</strong> In this study, Ag and TiO2 nanoparticles were synthesized, and the minimum inhibitory and bactericidal concentrations (MIC & MBC) were determined. In addition, the cytotoxicity of these agents was evaluated on Hu02 fibroblast cell line.<br> <strong>Results:</strong> We found that the MIC and MBC for Ag and TiO2 nanoparticles were similar (12.5 &micro;g/ml) against S. aureus, while the MIC&rsquo;s for Ag and TiO2 against S. dysenteriae were found to be 12.5 and 25 &micro;g/ml. In addition, the MBC&rsquo;s for Ag and TiO2 against S. dysenteriae were 25 and 50 &micro;g/ml. Based on the cytotoxicity tests, the cell viability percentage after 48 hours of exposure to TiO2 was higher than that of Ag (0.025 &micro;g/ml).<br> <strong>Conclusion:</strong> The Ag and TiO2 nanoparticles demonstrated good antibacterial properties while they had low toxicity against the Hu02 fibroblast cell line.<br> &nbsp;</p> Ag, Nanoparticles, Shigella dysenteria, Staphylococcus aureus, TiO2 9 16 http://ijt.arakmu.ac.ir/browse.php?a_code=A-10-1048-2&slc_lang=en&sid=1 Somayeh Soleymanzadeh Moghadam so.soleymanzadeh@gmail.com 100319475328460015119 100319475328460015119 No Antimicrobial Resistance Research Centre, Institute of Immunology and infection diseases, Iran University of Medical Sciences. Tehran, Iran Maliheh Nobakht Nokhabt@yahoo.com 100319475328460015120 100319475328460015120 No Antimicrobial Resistance Research Centre, Institute of Immunology and infection diseases, Iran University of Medical Sciences. Tehran, Iran Zahra Mohammadi drmohammadi75@yahoo.com 100319475328460015121 100319475328460015121 No Department of Pharmaceutics, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran Soheil Rahmani Fard Soheilgman@gmail.com 100319475328460015122 100319475328460015122 No Antimicrobial Resistance Research Centre, Institute of Immunology and infection diseases, Iran University of Medical Sciences. Tehran, Iran Farideh Hajian Hossein Abadi farideh.hajiyan@gmail.com 100319475328460015123 0009-0004-5212-9233 No Antimicrobial Resistance Research Center, Institute of Immunology and Infectious Diseases, Iran University of Medical Sciences, Tehran, Iran Samaneh Mazar Atabaki samaneh.atabaki@yahoo.com 100319475328460015124 100319475328460015124 No Antimicrobial Resistance Research Center, Institute of Immunology and Infectious Diseases, Iran University of Medical Sciences, Tehran, Iran Pedram Ebrahimnejad pebrahimnejad@mazums.ac.ir 100319475328460015125 100319475328460015125 Yes Department of Pharmaceutics, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran