Cytotoxic, genotoxic and the hemolytic effect of titanium dioxide (TiO₂) nanoparticles on human erythrocyte and lymphocyte cells in vitro

Abstract

With the increasing clinical use of titanium dioxide (TiO2 ) nanoparticles, a better understanding of their safety in the blood stream is required. The present study evaluates the toxic effect of commercially available TiO2 nanoparticles (~100 nm) using a battery of cytotoxic, genotoxic, hemolytic and morphological parameters. The cytotoxic effects of TiO2 nanoparticles in human lymphocyte cells were studied with respect to membrane damage, mitochondrial function, metabolic activity and lysosomal membrane stability. Genotoxicity in lymphocyte cells was quantitated using a comet assay. The mode of cell death (apoptosis/necrosis) was evaluated using PI/Annexin V staining. TiO2 nanoparticles were also evaluated for their hemolytic properties, osmotic fragility and interaction with hemoglobin. Human erythrocyte cells were studied for morphological alterations using atomic force microscopy (AFM). Results suggest that the particles could induce a significant reduction in mitochondrial dehydrogenase activity in human lymphocyte cells. Membrane integrity remained unaffected by nanoparticle treatment. DNA damage and apoptosis were induced by TiO2 nanoparticles in a dose-dependent manner. A study on human erythrocyte cells revealed a hemolytic property of TiO2 nanoparticles characterized by spherocytosis and echinocytosis. Spectral analysis revealed a hemoglobin TiO2 nanoparticle interaction. Our in vitro study results suggest that commercially available blood contacting nanoparticles (TiO2 nanoparticle) should be carefully evaluated for their toxic potential.

The effect of humic acid on the aggregation of titanium dioxide nanoparticles under different pH and ionic strengths

“…NanoTiO 2 had positive effects on root elongation in some species (Song et al, 2013). TiO 2 NPs have cytotoxic, genotoxic and hemolytic effects on human erythrocyte and lymphocyte cells in vitro and can induce a significant reduction in mitochondrial dehydrogenase activity in human lymphocyte cells (Ghosh et al, 2013). Nanoparticles can be transported in the human body, deposited in organs, transferred across cell membranes and accumulated in mitochondria, causing damage to humans (Colvin, 2003).…”

Heteroaggregation of engineered nanoparticles and kaolin clays in aqueous environments

“…Westerhoff et al found effluent concentrations of TiO 2 NPs in WWTPs were still 25 mg/L titanium, even though the WWTPs removed more than 96% of the influent titanium (Westerhoff et al, 2011). The increasing understanding of the toxicity (Chen et al, 2006;Colvin, 2003;De Jong et al, 2013;Ghosh et al, 2013;Keller et al, 2010;Olmedo et al, 2005;Song et al, 2013;Trouiller et al, 2009;Zhang et al, 2007) of these NPs indicates that their potential risk can't be ignored, therefore, their fate, transport and removal need to be better understood.…”

In Vitro Cyto-genotoxicity of Hydroxycitric Acid: A Weight-loss Dietary Supplement

“…Cell populations with >98% viability, as determined by TB test, were used. 16 Erythrocytes were separated as previously described by Ghosh et al 17 and diluted in phosphatebuffered saline (PBS) to a concentration of 2×10 6 cells/mL.…”

“…17 The degree of hemolysis was estimated by measuring the absorbance of the supernatant at 540 nm (Beckman Coulter). Results are expressed as:…”