Toxicity assessment of silica coated iron oxide nanoparticles and biocompatibility improvement by surface engineering.
We have studied in vitro toxicity of iron oxide nanoparticles (NPs) coated with a thin silica shell (Fe3O4/SiO2 NPs) on A549 and HeLa cells. We compared bare and surface passivated Fe3O4/SiO2 NPs to evaluate the effects of the coating on the particle stability and toxicity. NPs cytotoxicity was investigated by cell viability, membrane integrity, mitochondrial membrane potential (MMP), reactive oxygen species (ROS) assays, and their genotoxicity by comet assay. Our results show that NPs surface passivation reduces the oxidative stress and alteration of iron homeostasis and, consequently, the overall toxicity, despite bare and passivated NPs show similar cell internalization efficiency. We found that the higher toxicity of bare NPs is due to their stronger in-situ degradation, with larger intracellular release of iron ions, as compared to surface passivated NPs. Our results indicate that surface engineering of Fe3O4/SiO2 NPs plays a key role in improving particles stability in biological environments reducing both cytotoxic and genotoxic effects.
Center for Biomolecular Nanotechnologies@UNILE, Istituto Italiano di Tecnologia, Arnesano, Italy.
Maria Ada
MA
Malvindi
Center for Biomolecular Nanotechnologies@UNILE, Istituto Italiano di Tecnologia, Arnesano, Italy.
Valeria
V
De Matteis
Center for Biomolecular Nanotechnologies@UNILE, Istituto Italiano di Tecnologia, Arnesano, Italy.
Antonio
A
Galeone
Center for Biomolecular Nanotechnologies@UNILE, Istituto Italiano di Tecnologia, Arnesano, Italy.
Virgilio
V
Brunetti
Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy.
George C
GC
Anyfantis
Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy.
Athanassia
A
Athanassiou
Istituto Italiano di Tecnologia, Genova, Italy.
Roberto
R
Cingolani
Center for Biomolecular Nanotechnologies@UNILE, Istituto Italiano di Tecnologia, Arnesano, Italy.
Pier Paolo
PP
Pompa
D002470:Cell Survival / Q000187:drug effects; D020099:Coated Materials, Biocompatible / Q000633:toxicity*; D003470:Culture Media / Q000494:pharmacology; D004249:DNA Damage; D004705:Endocytosis / Q000187:drug effects; D005290:Ferric Compounds / Q000633:toxicity*; D006367:HeLa Cells; D006801:Humans; D008422:Materials Testing; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D053758:Nanoparticles / Q000633:toxicity* / Q000648:ultrastructure; D036103:Nanotechnology / Q000379:methods*; D017382:Reactive Oxygen Species / Q000378:metabolism; D012822:Silicon Dioxide / Q000633:toxicity*; D013499:Surface Properties; D018675:Toxicity Tests
D020099:Coated Materials, Biocompatible; D003470:Culture Media; D005290:Ferric Compounds; D017382:Reactive Oxygen Species; C000499:ferric oxide; D012822:Silicon Dioxide