Genotoxicity assessment of magnetic iron oxide nanoparticles with different particle sizes and surface coatings

Abstract

Magnetic iron oxide nanoparticles (IONPs) have been widely used for various biomedical applications such as magnetic resonance imaging and drug delivery. However, their potential toxic effects, including genotoxicity, need to be thoroughly understood. In the present study, the genotoxicity of IONPs with different particle sizes (10, 30 nm) and surface coatings (PEG, PEI) were assessed using three standard genotoxicity assays, the Salmonella typhimurium reverse mutation assay (Ames test), the in vitro mammalian chromosome aberration test, and the in vivo micronucleus assay. In the Ames test, SMG-10 (PEG coating, 10 nm) showed a positive mutagenic response in all the five test bacterial strains with and without metabolic activation, whereas SEI-10 (PEI coating, 10 nm) showed no mutagenesis in all tester strains regardless of metabolic activation. SMG-30 (PEG coating, 30 nm) was not mutagenic in the absence of metabolic activation, and became mutagenic in the presence of metabolic activation. In the chromosomal aberration test, no increase in the incidence of chromosomal aberrations was observed for all three IONPs. In the in vivo micronucleus test, there was no evidence of increased micronuclei frequencies for all three IONPs, indicating that they were not clastogenic in vivo. Taken together, our results demonstrated that IONPs with PEG coating exhibited mutagenic activity without chromosomal and clastogenic abnormalities, and smaller IONPs (SMG-10) had stronger mutagenic potential than larger ones (SMG-30); whereas, IONPs with SEI coating (SEI-10) were not genotoxic in all three standard genotoxicity assays. This suggests that the mutagenicity of IONPs depends on their particle size and surface coating.

Environmental implications and applications of engineered nanoscale magnetite and its hybrid nanocomposites: A review of recent literature

“…The mutagenicity of MNPs depend on their particle size and surface coating. MNPs with PEG coating exhibit mutagenic activity without chromosomal and clastogenic abnormalities, and smaller MNPs (10 nm) have stronger mutagenic potential than larger ones (30 nm); whereas, MNPs with PEI coating are not genotoxic in all three standard genotoxicity assays [109]. In another study, SPIONs are found not toxic to cells in cell viability assays [110].…”

Iron oxide nanoparticles decrease nuclear fractal dimension of buccal epithelial cells in a time‐dependent manner

“…For example, Liu et al . () indicated that IONPs with PEG coating exhibited mutagenic properties, and that smaller IONPs might be more genotoxic. Also, in a recent article, Valdiglesias et al .…”

“…Some authors have already indicated that IONPs have some genotoxic potential, which depends on particle size and surface coatings. For example, Liu et al (2014) indicated that IONPs with PEG coating exhibited mutagenic properties, and that smaller IONPs might be more genotoxic. Also, in a recent article, Valdiglesias et al (2015) stated that toxic potential of iron oxide nanoparticles with superparamagnetic properties may largely depend on particle diameter and surface modifications.…”

Evaluation of cytotoxicity and genotoxicity induced by oleic acid‐coated iron oxide nanoparticles in human astrocytes

“…In this way, several previous studies using different cell systems reported the lack of MN induction after ION exposure. Specifically, in Chinese hamster lung cells exposed to poly(ethylene imine)‐coated ION (Liu et al ) or exposed to glutamic acid‐coated ION (Zhang et al ); in human lymphoblastoid cells treated with uncoated maghemite or with uncoated and dextran‐coated magnetite (Singh et al ); and in human SH‐SY5Y neurons exposed to silica‐coated ION (Kiliç et al ), among others. Accordingly, and considering all results obtained in this study from genotoxicity tests, O‐ION exposure induced primary DNA damage, as revealed by γH2AX analysis and, particularly, comet assay, but A172 cells were apparently able to repair this damage avoiding its fixation as chromosome alterations (MN).…”