Citation
Field, James A.; Luna-Velasco, Antonia; Boitano, Scott A.; Shadman, Farhang; Ratner, Buddy D.; Barnes, Chris; & Sierra-Alvarez, Reyes (2011).
Cytotoxicity and physicochemical properties of hafnium oxide nanoparticles.
Chemosphere, 84(10), 1401-1407.
Abstract
Nano-sized hafnium oxide (HfO2) particles are being considered for applications within the semiconductor industry. However, little is known about their cytotoxicity. The objective of this work was to assess several HfO2 nanoparticles (NPs) samples for their acute cytotoxicity. Dynamic light scattering analysis of the samples indicated that the average particle size of the HfO2 in aqueous dispersions was in the submicron range with a fraction of particles having nano-dimensions. The media used in the toxicity assays decreased or increased the average particle size of HfO2 NPs due to dispersion or agglomeration. Static time-of-flight secondary ion mass spectrometry (ToF-SIMS) revealed numerous surface contaminants on the NPs. Only one HfO2 sample caused moderate cytotoxicity to human cell lines. The inhibitory sample caused a 50% response in the Live/Dead assay with HaCaT skin cells at 2200 mg L-1; and a 50% response in the mitochondrial toxicity test at 300 mg L-1. A microbial inhibition assay based on methanogenic activity also revealed that another HFO2 sample caused moderate inhibition. The difference in toxicity between samples could not be attributed to size. Instead the difference in toxicity was likely due to differences in the contaminants of the HfO2. The ToF-SIMS analysis indicated unique signatures of Br and P in the sample toxic to human cell lines suggesting a distinct synthesis was used for that sample which may have been accompanied by inhibitory impurities. The results taken as a whole indicate that HfO2 itself is relatively non-toxic.
Keyword(s)
HfO2NanotoxicitySIMSSurface chemistry
Reference Type
Journal Article
Secondary Title
Chemosphere
Author(s)
Field, James A.Luna-Velasco, AntoniaBoitano, Scott A.Shadman, FarhangRatner, Buddy D.Barnes, ChrisSierra-Alvarez, Reyes
Year Published
2011
Volume Number
84
Issue Number
10
Pages
1401-1407
DOI
10.1016/j.chemosphere.2011.04.067
