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bioRxiv · 10.1101/2022.05.23.492822

The electric field generated by cationic TiO2 nanoparticles can be their key antimicrobial factor

Zhukova, L. V.
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Abstract

The antimicrobial effect of TiO2 nanoparticles (TiO2 NPs) has been reliably established. However, the mechanism of this action remains unclear. Currently, according to the dominant hypothesis, it is assumed that the key destructive mechanism is the photocatalytic oxidation of cell components, and the key antimicrobial factor is the reactive oxygen species (ROS) formed on the surface of TiO2 NPs as a result of photocatalysis. In this communication, for the first time, the influence of the electric field created by cationic TiO2 NPs is suggested as a key killing factor, and the key antimicrobial mechanism - the electrical breakdown of the cell membranes and the destruction of the DNA molecule under the action of this field. Here, it was shown by mathematical calculation that TiO2 NPs are able to generate an electric field with a strength sufficient for an electrical breakdown of bilayer lipid membranes, which can lead to a violation of the structure and vital functions of the cytoplasmic membrane (CPM) and to collapse of DNA molecule. GRAPHICAL ABSTRACT O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

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Zhukova, L. V.. 2022-05-24. The electric field generated by cationic TiO2 nanoparticles can be their key antimicrobial factor. https://doi.org/10.1101/2022.05.23.492822

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