Cellular Internalization of Dissolved Cobalt Ions from Ingested CoFe₂O₄ Nanoparticles: In Vivo Experimental Evidence

Abstract

With a model invertebrate animal, we have assessed the fate of magnetic nanoparticles in biologically relevant media, i.e., digestive juices. The toxic potential and the internalization of such nanoparticles by nontarget cells were also examined. The aim of this study was to provide experimental evidence on the formation of Co(2+), Fe(2+), and Fe(3+) ions from CoFe₂O₄ nanoparticles in the digestive juices of a model organism. Standard toxicological parameters were assessed. Cell membrane stability was tested with a modified method for measurement of its quality. Proton-induced X-ray emission and low energy synchrotron radiation X-ray fluorescence were used to study internalization and distribution of Co and Fe. Co(2+) ions were found to be more toxic than nanoparticles. We confirmed that Co(2+) ions accumulate in the hepatopancreas, but Fe(n+) ions or CoFe₂O₄ nanoparticles are not retained in vivo. A model biological system with a terrestrial isopod is suited to studies of the potential dissolution of ions and other products from metal-containing nanoparticles in biologically complex media.

Analytical approaches to support current understanding of exposure, uptake and distributions of engineered nanoparticles by aquatic and terrestrial organisms

“…ions released after ENP dissolution in the gut lumen or after cellular uptake, rather than by intact particles. Similar effects related to potentially assimilated dissolved ions have also been reported in isopods exposed to diets containing a range of heavy metals (Golobič et al 2012;Novak et al 2013). These findings are consistent with a hypothesis suggesting that dissolved ions play a key role in ENP ecotoxicology.…”

Toxicity of cobalt ferrite (CoFe2O4) nanobeads in Chlorella vulgaris: Interaction, adaptation and oxidative stress

“…Large-scale use of CoFe 2 O 4 NPs results in their waste disposal into the environment, raising an alarming situation (Novak et al, 2013) for the global ecosystem. Natural organic matter can promote degradation of CoFe 2 O 4 NPs resulting in possible release of Co 2+ and Fe 3+ ions into the environment.…”

“…Natural organic matter can promote degradation of CoFe 2 O 4 NPs resulting in possible release of Co 2+ and Fe 3+ ions into the environment. Co 2+ and Fe 3+ ions can induce ROS mediated oxidative stress (Novak et al, 2013;Sun et al, 2013), cytotoxicity, genotoxicity, inflammations (Papis et al, 2007;Ponti et al, 2009) and cause oxidation of proteins and membrane disruptions (Azaria et al, 2011;Luo et al, 2014). There is therefore a pressing need to study the possible toxic effects by the release of CoFe 2 O 4 NPs and subsequent dissolution of ions from NPs at the disposal of the environment.…”

An in vivo evaluation of acute toxicity of cobalt ferrite (CoFe2O4) nanoparticles in larval-embryo Zebrafish (Danio rerio)

“…stress (Novak et al, 2013;Sun et al, 2013), cytotoxicity, genotoxicity, inflammations and oxidation of proteins and membrane disruptions (Papis et al, 2007;Ponti et al, 2009;Azaria et al, 2011;Luo et al, 2014). Therefore, there is pressing need to study the possible toxic effects of CoFe 2 O 4 NPs and subsequent dissolution of ions from these NPs into the environment.…”