In Memoriam

Abstract

The present study aims to study antibacterial effects and cellular mechanisms of iron oxide magnetic nanoparticles loaded with piroctone olamine ([email protected] NPs) against some cariogenic bacteria (Streptococcus mutans and Actinomyces viscosus).Nanoparticles was synthesized by the coprecipitation method. Antibacterial effects of [email protected] NPs were performed by calculating the minimum inhibitory concentration (MIC). We also evaluated the level of reactive oxygen species (ROS) and protein leakage to assess whether antibacterial effects may be dependent on these mechanisms.The results demonstrated that PO showed the lowest antibacterial effect compared to other drugs tested with MICs values of 53.33 and 64 μg/ml for S. mutans and A. viscosus, respectively. In contrast, the highest antibacterial effect was related to [email protected] with MICs values of 2.66 and 3.33 μg/ml for S. mutans and A. viscosus, respectively. [email protected], Fe3O4MNP, and PO markedly increased (p < 0.001) ROS production and protein leakage of tested bacteria at ≥¼ MIC, ≥1/3 MIC, and ½ MIC, respectively.The findings of the present survey revealed the promising antibacterial effects of [email protected] against some cariogenic bacteria; whereas it triggered the ROS production and protein leakage as the possible antibacterial mode of action of anti-infective agents. However, additional surveys are necessary to elucidate the accurate mechanisms of these nanoparticles.