Evaluating the biological risk of functionalized multiwalled carbon nanotubes and functionalized oxygen-doped multiwalled carbon nanotubes as possible toxic, carcinogenic, and embryotoxic agents

Abstract

Carbon nanotubes (CNTs) have been a focus of attention due to their possible applications in medicine, by serving as scaffolds for cell growth and proliferation and improving mesenchymal cell transplantation and engraftment. The emphasis on the benefits of CNTs has been offset by the ample debate on the safety of nanotechnologies. In this study, we determine whether functionalized multiwalled CNTs (fMWCNTs) and functionalized oxygen-doped multiwalled CNTs (fCOxs) have toxic effects on rat mesenchymal stem cells (MSCs) in vitro by analyzing morphology and cell proliferation and, using in vivo models, whether they are able to transform MSCs in cancer cells or induce embryotoxicity. Our results demonstrate that there are statistically significant differences in cell proliferation and the cell cycle of MSCs in culture. We identified dramatic changes in cells that were treated with fMWCNTs. Our evaluation of the transformation to cancer cells and cytotoxicity process showed little effect. However, we found a severe embryotoxicity in chicken embryos that were treated with fMWCNTs, while fCOxs seem to exert cardioembryotoxicity and a discrete teratogenicity. Furthermore, it seems that the time of contact plays an important role during cell transformation and embryotoxicity. A single contact with fMWCNTs is not sufficient to transform cells in a short time; an exposure of fMWCNTs for 2 weeks led to cell transformation risk and cardioembryotoxicity effects.

Migration of mesenchymal stem cells tethered with carbon nanotubes under a chemotactic gradient

“…Moreover, the steps involved in anchoring nanomaterials are much less than the ones reported by Yao et al 28 Cytotoxicity is one of the major concerns when nanoparticles such as AuNPs or CNTs were internalized by MSCs for 24 h or longer. 34,35 A previous study showed that culture medium containing over 32 mg mL À1 CNTs causes toxicity to MSCs aer 6 days of culture, while reducing concentration to 6.4 mg mL À1 showed lower toxicity effect. 36 Another study showed that cellular uptake of AuNPs can cause a dose-dependent cytotoxicity to MSCs.…”

Influence of functional groups on toxicity of carbon nanomaterials

“…Their basic structure is that of graphite with planes of honeycomb-structured carbon atoms. Carbon black (CB), which is produced from incomplete combustion of heavy petroleum materials under controlled conditions (Apicella et al, 2003), has been widely used in industrial products, such as inkjet printer ink, rubber and plastic products (Lee et al, 2016); electrically conductive plastics (Parant et al, 2017); paints, coatings and cosmetics (Sanders and Peeten, 2011); and so on. CB is a quasi-graphitic form of nearly pure elemental carbon (EC, consists of graphene layers).…”

“…However, it is possible to investigate the role of functional groups in the toxicity of carbon nanomaterials when using CB or engineered carbon particles with different functional groups as model samples of soot particles. Actually, it has been recognized that the surface properties of carbon nanomaterials will influence their biological effects or toxicity (Lara-Martinez et al, 2017;Koromilas et al, 2014). For example, a recent study has found that hydrated graphene oxide exhibited a higher cytotoxicity to THP-1 (a human monocytic leukemia cell line) and BEAS-2B (human bronchial epithelial) cells as a consequence of lipid peroxidation of the surface membrane and membrane lysis compared to pristine and reduced graphene oxide (Li et al, 2018).…”

“…For example, a recent study has found that hydrated graphene oxide exhibited a higher cytotoxicity to THP-1 (a human monocytic leukemia cell line) and BEAS-2B (human bronchial epithelial) cells as a consequence of lipid peroxidation of the surface membrane and membrane lysis compared to pristine and reduced graphene oxide (Li et al, 2018). Functionalized multiwalled carbon nanotubes (FMWCNTs) are highly cardioembryotoxic in comparison to functionalized oxygen-doped multiwalled carbon nanotubes (Lara-Martinez et al, 2017). As pointed out by Lara-Martinez et al 2017, however, cytotoxic effects of carbon nanomaterials at the cellular level generate considerable controversy and more research is clearly needed to gain insight into the mechanism of these adverse effects.…”

Influence of functional groups on toxicity of carbon nanomaterials: implication for toxicological evolution during atmospheric relevant aging of soot

“…Therefore, it is possible to investigate the role of functional groups in the toxicity of soot when using CB or engineered carbon particles with different functional groups as model sample of soot particles. Actually, it has been recognized that the surface properties of carbon nanomaterials will influence their biological effects or toxicity (Lara-Martinez et al, 2017;Liu et al, 2014b;Koromilas et al, 2014). For example, a recent study has found that hydrated graphene oxide exhibited a higher cytotoxicity to THP-1 and BEAS-2B cells as a consequence of lipid peroxidation of the surface membrane and membrane lysis compared to pristine and reduced graphene oxide (Li et al, 2018).…”