Size-dependent cytotoxicity of copper oxide nanoparticles in lung epithelial cells

Abstract

The increasing use of copper oxide (CuO) nanoparticles (NPs) in medicine and industry demands an understanding of their potential toxicities. In this study, we compared the in vitro cytotoxicity of CuO NPs of two distinct sizes (4 and 24 nm) using the A549 human lung cell line. Despite possessing similar surface and core oxide compositions, 24 nm CuO NPs were significantly more cytotoxic than 4 nm CuO NPs. The difference in size may have affected the rate of entry of NPs into the cell, potentially influencing the amount of intracellular dissolution of Cu2+ and causing a differential impact on cytotoxicity.

The roles of surface chemistry, dissolution rate, and delivered dose in the cytotoxicity of copper nanoparticles

“…45 Wongrakpanich et al stated that the difference in CuO NPs size might have affected the rate of entry of NPs into the cell, potentially influencing the amount of intracellular dissolution of Cu 2+ and causing a differential impact on cytotoxicity. 46 Our results support this mechanism for more slowly-dissolving Cu-based NPs, but show that detrimental effects on cell health could be particle uptake-independent. Specifically, a change in NP surface chemistry results in different mechanisms of dissolution and, thus, interactions with cells.…”

Rational approaches for toxicological assessments of nanobiomaterials

“…There are various factors like internalization process, physicochemical characteristics of NM (size, shape, surface area, surface chemistry, etc) which could be determinant factor for biological activity/toxicity of NM (Figure ). Various experiments studies have demonstrated these physicochemical properties as a responsible factor for biological toxicity of NM . Size of NM is a determinant factor for its cellular uptake, most of small size NM has been observed to follow caveola, clathrin coated pits mediated endocytosis while uptake of larger particles have been reported to follow phagocytosis process (Figure ).…”

Assessing the effect of engineered nanomaterials on the environment and human health

“…As an example, we have recently shown that CuO ENs (nanoparticles), physically and chemically similar in all respects apart from size (4 nm versus 24 nm) had significantly different impacts on viability of, and ROS production in, lung cells [6]. The finding that 4 nm CuO NPs were less toxic than 24 nm CuO NP coincided with lower intracellular levels of Cu for the former suggesting that the smaller NPs (on a per weight basis) were less readily taken up by the lung cells in vitro.…”