The colony formation assay as an indicator of carbon nanotube toxicity examined in three cell lines

Abstract

The cytotoxicity of multiwall carbon nanotubes (MWCNT) was studied in three different cell lines; rat brain endothelial cells (RBE4), a rapidly dividing epithelial like human cell line originating from a cervix carcinoma (NHIK3025) and a human lung carcinoma cell line (A549). The colony formation assay was used as end point to avoid sample interference in colorimetric assays. It was possible to differentiate between four different types of MWCNTs in concentrations between 2 and 20 µg/ml with this method. There was a great difference in sensitivity between the three cell lines. RBE4 cells were best suited for this assay within this concentration range. The results show that the clonogenic assay has the potential to be a useful tool in the cytotoxicity testing of carbon based nanomaterials even at low concentrations provided a suitable cell line is used.

• Carbon nanotubes
• colony formation assay
• cytotoxicity
• nanotoxicology