A Mechanism of the Interaction of Metal Oxide Nanoparticles with Biological Membranes

Abstract

Abstract—Advances in nanotechnologies and artificial methods for the synthesis of metal oxide nanoparticles with sizes of 1–100 nm raise the issue of their biological safety. Nanoparticles with a size of less than 10 nm are capable of penetrating into the bloodstream, followed by their entry into various organs, such as the brain, liver, kidneys, lungs, and spleen. Nanoparticles are a pathogenic exogenous factor that disturbs the structure and functions of natural biomembranes. We have previously shown using in vitro studies that nanoparticles with a diameter below a critical value of Rcr permeate the membrane. As a result, the microviscosity of the lipid bilayer of biomembranes decreases. This process is accompanied by the formation of through pores, which can combine into cracks and destroy the membrane. If the radius of the nanoparticles is greater than a critical value they are adsorbed on the membrane surface, thus increasing their microviscosity. In both cases, nanoparticles disrupt the normal functioning of natural biomembranes and cells. This paper presents a thermodynamic model of the direct (not due to endocytosis) penetration of nanoparticles into the lipid bilayer of the membrane. It has been shown that the Rcr value increases with an increase in the Zeta potential of the nanoparticles.