In Vitro and In Silico Study of Cytotoxicity of Metal Oxide Nanoparticles towards Escherichia coli

Graphical Abstract Abstract. In continuation of study of 17 metal oxide nanoparticles (MNPs) cytotoxicity to E. coli after 2 hrs. exposure under dark conditions, we have evaluated cytotoxicity of additional 8 MNPs maintaining equivalent experiemental conditions following the literature The overall cytotoxicity ranking of these additional MNPs according to LC 50 values in descending order is Er 2 O 3 , Gd 2 O 3 , CeO 2 , Co 2 O 3 , Mn 2 O 3 , Co 3 O 4 , Fe 3 O4/WO 3 . The in vitro study clearly suggested that Er 2 O 3 and Gd 2 O 3 are the most toxic among all 25 MNPs under the mentioned experiemental conditions. The present experiemental data is one of the biggest available nano metal oxide cytotoxicity data for E. coli at present time performed under similar experimental conditions and same laboratory. Therefore, the obtained data is significant in terms of OECD principle 1 of defined endpoint to develop statistically acceptable and predictive in silico models. As two MNPs, WO 3 and Fe 3 O 4