Evaluating the Cytotoxicity of Monolayered and Multilayered Carbon Nanotubes on Three Different Human Cell Lines

Background: Nanotechnology and nanobiotechnology have emerged as novel technologies for the production and application of nanoscale materials in different pharmaceutical, medical, and biological fields. Besides, there are a bunch of recently published patents in this field. Although Carbon Nanotubes (CNTs) have various advantages and can be applied for a wide variety of purposes, their toxicity on humans is a matter of concern. Objective: This study aimed to evaluate six different types of CNTs, including pristine, carboxylated, and hydroxylated single-walled CNTs (SWCNTs) and multi-walled CNTs (MWCNTs) on three human cell lines. Methods: MTT assay was employed to assess the cytotoxicity of six types of CNTs, including pristine, carboxylated, and hydroxylated forms of SWCNTs and MWCNTs on three different human cell lines. Results: The findings of the MTT assay showed that the six different types of CNTs (100- 600 μg/mL) exhibited different levels of cytotoxicity on the three human cell lines. The observed trend presented dose-dependent cytotoxicity on the three studied cell lines, including pulmonary, skin, and gastrointestinal cell lines. SWCNT-COOH and MWCNTs accounted for the lowest cell viability in the three human cell lines. Conclusion: In conclusion, researchers and industrial workers are recommended to be cautious while working with different types of CNT because all their toxicity dimensions have not been determined yet.