Journal for Biophysical Chemistry

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Open Access

Comparative cytotoxicity evaluation of lanthanide nanomaterials on mouse and human cell lines with metabolic and DNA-quantification assays

  • Boon Chin Heng1,
  • Gautom Kumar Das2,
  • Xinxin Zhao1,
  • Lwin-Lwin Ma1,
  • Timothy Thatt-Yang Tan2,
  • Kee Woei Ng1Email author,
  • Joachim Say-Chye Loo1Email author and
  • Lwin-Lwin Ma1

Received: 17 August 2010

Accepted: 9 September 2010

Published: 14 December 2010


Lanthanide nanomaterials are considered a less toxic alternative to quantum dots for bioimaging applications. This study evaluated the cytotoxicity of terbium (Tb)-doped gadolinium oxide (Gd2O3) and dysprosium oxide (Dy2O3) nanoparticles exposed to human (BEAS-2B) and mouse (L929) cell lines at a concentration range of 200–2000 (μg/ml for 48 h. Two assay methods were utilized—WST-8 assay (colorimetric) based on mitochondrial metabolic activity and Pico-Green assay (fluorescence), which measures total DNA content. The authors' data showed that Tb-doped Gd2O3 nanoparticles were consistently more toxic than Tb-doped Dy2O3 nanoparticles. However, exposure to these nanomaterials caused a decrease in proliferation rate for both cell lines rather than a net loss of viable cells after 48 h of exposure. Additionally, there was some degree of discrepancy observed with the two assay methods. For the mouse L929 cell line, the WST-8 assay yielded consistently lower proliferation rates compared to the Pico-Green assay, whereas the opposite trend was observed for the human BEAS-2B cell line. This could arise because of the differential effects of these nanoparticles on the metabolism of L929 and BEAS-2B cells, which in turn may translate to differences in their postexposure proliferation rates. Hence, the Pico-Green assay could have an advantage over the WST-8 assay because it is not skewed by the differential effects of nanomaterials on cellular metabolism.