The effects of engineered nanoparticles on the cellular structure and growth ofSaccharomyces cerevisiae

Abstract

In order to study the effects of nanoparticles (NPs) with different physicochemical properties on cellular viability and structure, Saccharomyces cerevisiae were exposed to different concentrations of TiO2-NPs (1-3 nm), ZnO-NPs (<100 nm), CuO-NPs (<50 nm), their bulk forms, Ag-NPs (10 nm) and single-walled carbon nanotubes (SWCNTs). The GreenScreen assay was used to measure cyto- and genotoxicity, and transmission electron microscopy (TEM) used to assess ultrastructure. CuO-NPs were highly cytotoxic, reducing the cell density by 80% at 9 cm(2)/ml, and inducing lipid droplet formation. Cells exposed to Ag-NPs (19 cm(2)/ml) and TiO2-NPs (147 cm(2)/ml) contained dark deposits in intracellular vacuoles, the cell wall and vesicles, and reduced cell density (40 and 30%, respectively). ZnO-NPs (8 cm(2)/ml) caused an increase in the size of intracellular vacuoles, despite not being cytotoxic. SWCNTs did not cause cytotoxicity or significant alterations in ultrastructure, despite high oxidative potential. Two genotoxicity assays, GreenScreen and the comet assay, produced different results and the authors discuss the reasons for this discrepancy. Classical assays of toxicity may not be the most suitable for studying the effects of NPs in cellular systems, and the simultaneous assessment of other measures of the state of cells, such as TEM are highly recommended.

Phytotoxicity, Translocation, and Biotransformation of NaYF4Upconversion Nanoparticles in a Soybean Plant

“…Compared with the diameters of 50 nm for the original UCNPs, we speculated that the decreased diameters of 12–30 nm could be attributed to the occurrence of biotransformation at the first day. To the best of our knowledge, the biotransformation of NPs is complicated in the biological system . According to the previous researches, phosphates such as PO 4 3− widely exist in the environmental and biological systems.…”

“…As an important component of the environment, plants play a significant role in preserving the ecological system equilibrium and can provide one of the main food sources of animals and human beings . Once nanoparticles (NPs) are absorbed by plants via an aerial or root pathway, and come into food webs, they could accumulate in organisms and cause possible biomagnification, which have been reported on nano‐TiO 2 and carbon nanotubes . Additionally, NPs may undergo transformations in a plant system, which will modify their ultimate toxicity and behavior in plants.…”

Toxicity of Ag, CuO and ZnO nanoparticles to selected environmentally relevant test organisms and mammalian cells in vitro: a critical review

“…As shown in Crane et al (2008), Kahru et al (2008) and Kahru and Dubourguier (2010), the types of test species and biological endpoints used within standard environmental hazard assessment frameworks are generally appropriate also for nanoecotoxicological purposes. The additional specific requirements for NP studies are the dispersion conditions and characterization of the particles in the test environment as well as careful consideration of test conditions for potential artifacts that can arise due to the color of NPs or their sorptive properties (Handy et al 2012; Schrurs and Lison 2012; Bayat et al 2013). Analogously to the rest of the chemical compounds, NPs are classified with respect to their environmental toxicity according to the response of the most sensitive of the three test organisms: algae, crustaceans and fish (European Union 2011).…”

Assessment of functionalized iron oxide nanoparticles in vitro: introduction to integrated nanoimpact index

“…46,47 The SPIONS studied here neither generated any increase in the ROS level ( Fig. Measurements of the SPIONs scavenge capacity of ROS such as superoxide anion and hydrogen peroxide has been evaluated in cells exposed to metal oxide SPIONs.…”