Toxicity of tungsten carbide and cobalt-doped tungsten carbide nanoparticles in mammalian cells in vitro.
BACKGROUND
Tungsten carbide nanoparticles are being explored for their use in the manufacture of hard metals. To develop nanoparticles for broad applications, potential risks to human health and the environment should be evaluated and taken into consideration.


OBJECTIVE
We aimed to assess the toxicity of well-characterized tungsten carbide (WC) and cobalt-doped tungsten carbide (WC-Co) nanoparticle suspensions in an array of mammalian cells.


METHODS
We examined acute toxicity of WC and of WC-Co (10% weight content Co) nanoparticles in different human cell lines (lung, skin, and colon) as well as in rat neuronal and glial cells (i.e., primary neuronal and astroglial cultures and the oligodendrocyte precursor cell line OLN-93). Furthermore, using electron microscopy, we assessed whether nanoparticles can be taken up by living cells. We chose these in vitro systems in order to evaluate for potential toxicity of the nanoparticles in different mammalian organs (i.e., lung, skin, intestine, and brain).


RESULTS
Chemical-physical characterization confirmed that WC as well as WC-Co nanoparticles with a mean particle size of 145 nm form stable suspensions in serum-containing cell culture media. WC nanoparticles were not acutely toxic to the studied cell lines. However, cytotoxicity became apparent when particles were doped with Co. The most sensitive were astrocytes and colon epithelial cells. Cytotoxicity of WC-Co nanoparticles was higher than expected based on the ionic Co content of the particles. Analysis by electron microscopy demonstrated presence of WC nanoparticles within mammalian cells.


CONCLUSIONS
Our findings demonstrate that doping of WC nanoparticles with Co markedly increases their cytotoxic effect and that the presence of WC-Co in particulate form is essential to elicit this combinatorial effect.
Department of Pediatric Neurology, University Children's Hospital Carl Gustav Carus, University of Technology Dresden, Dresden, Germany.
Susanne
S
Bastian
Wibke
W
Busch
Dana
D
Kühnel
Armin
A
Springer
Tobias
T
Meissner
Roland
R
Holke
Stefan
S
Scholz
Maria
M
Iwe
Wolfgang
W
Pompe
Michael
M
Gelinsky
Annegret
A
Potthoff
Volkmar
V
Richter
Chrysanthy
C
Ikonomidou
Kristin
K
Schirmer
D000818:Animals; D018938:Caco-2 Cells; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003035:Cobalt / Q000737:chemistry / Q000633:toxicity*; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D053768:Metal Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D009836:Oligodendroglia / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D017973:Tungsten Compounds / Q000737:chemistry / Q000633:toxicity*
D017973:Tungsten Compounds; C002802:tungsten carbide; D003035:Cobalt