Toxicity of Graphene Oxide on Intestinal Bacteria and Caco-2 Cells

Nguyen, Trang Ha; Lin, Mengshi; Mustapha, Azlin

doi:10.4315/0362-028x.jfp-14-463

Cited by 48 publications

(35 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, treatments with nondigested GRMs, used as controls, further indicated neither significant decrease in cell viability, nor damage of cell membrane ( Figure S5b,c, Supporting Information), in line with previously reported data on the same cell type. [18,19] Therefore, lack of cytotoxicity in these cells after exposure to digested GRMs likely suggests no toxicity on intestinal barrier, as well.…”

Section: Cellular Uptake and Intracellular Localization Of Digested Grmsmentioning

confidence: 99%

Biotransformation and Biological Interaction of Graphene and Graphene Oxide during Simulated Oral Ingestion

Guarnieri

Sánchez-Moreno

Castillo

et al. 2018

Small

View full text Add to dashboard Cite

The biotransformation and biological impact of few layer graphene (FLG) and graphene oxide (GO) are studied, following ingestion as exposure route. An in vitro digestion assay based on a standardized operating procedure (SOP) is exploited. The assay simulates the human ingestion of nanomaterials during their dynamic passage through the different environments of the gastrointestinal tract (salivary, gastric, intestinal). Physical-chemical changes of FLG and GO during digestion are assessed by Raman spectroscopy. Moreover, the effect of chronic exposure to digested nanomaterials on integrity and functionality of an in vitro model of intestinal barrier is also determined according to a second SOP. These results show a modulation of the aggregation state of FLG and GO nanoflakes after experiencing the complex environments of the different digestive compartments. In particular, chemical doping effects are observed due to FLG and GO interaction with digestive juice components. No structural changes/degradation of the nanomaterials are detected, suggesting that they are biopersistent when administered by oral route. Chronic exposure to digested graphene does not affect intestinal barrier integrity and is not associated with inflammation and cytotoxicity, though possible long-term adverse effects cannot be ruled out.

show abstract

Section: Cellular Uptake and Intracellular Localization Of Digested Grmsmentioning

confidence: 99%

Biotransformation and Biological Interaction of Graphene and Graphene Oxide during Simulated Oral Ingestion

Guarnieri

Sánchez-Moreno

Castillo

et al. 2018

Small

View full text Add to dashboard Cite

show abstract

“…Although the toxicity of GO to organisms is unclear, some recent studies showed that GO caused cytotoxicity in some bacteria and cells (Combarros et al, 2016;Nguyen et al, 2015), while another recent study reported that purified GO did not have in-vitro cytotoxicity (Ali-Boucetta et al, 2013). Moreover, the environmental impact of GO on some organisms and the fate of inorganic substances can be significant (Mukherjee et al, 2016;Zhao et al, 2014).…”

Section: Introductionmentioning

confidence: 97%

Effect of co-existing kaolinite and goethite on the aggregation of graphene oxide in the aquatic environment

et al. 2016

View full text Add to dashboard Cite

Broad applications of graphene oxide (GO) will result in the release of GO into aquatic environments, where clay minerals and metal (hydr)oxides are commonly present. Thereby the interactions between GO and a binary system containing clay minerals and metal (hydr)oxides can occur. We investigated the aggregation of GO with kaolinite and kaolinite-goethite associations (KGAs) in aquatic systems under different pHs, ionic strengths, and GO concentrations. GO suspension was unstable at low pHs, and the aggregation of GO occurred in the presence of KGA-4% and KGA-10% until pH 5 and 6, respectively. Kaolinite decreased the critical coagulation concentration (CCC) of GO at pH 5.5 from around 50 to 20 mM NaCl due to the reduced energy barrier. Heteroaggregation of GO with KGAs was extremely sensitive to ionic strength at pH 5.5, and the CCC of GO in the presence of KGA-10% increased from less than 1 mM NaCl to 5 mM NaCl with the increase of pH from 5.5 to 9. The heteroaggregation extent of GO with KGAs was enhanced firstly, then reduced with the increase of GO concentrations at pH 5.0, which is likely because KGA plates were more efficiently wrapped by large-size GO sheets with increasing GO concentrations. These findings are useful for understanding and predicting the fate of GO in the relatively complicated aquatic and soil environments where binary minerals co-exist.

show abstract

“…Therefore it is an important point to obtain clear evidence that GO traces are not harmful upon casual ingestion. Only recently the impact of different GO on undifferentiated Caco-2 cells has been reported [19–21], revealing the formation of reactive oxygen species (ROS) induced by GO as well as a close GO-cell surface interaction. Nevertheless no acute toxicity of the applied GO for an exposure range of 5–80 µg GO/ml and an exposure time up to 48 h could be found [20].…”

Section: Introductionmentioning

confidence: 99%

Uptake of label-free graphene oxide by Caco-2 cells is dependent on the cell differentiation status

et al. 2017

View full text Add to dashboard Cite

BackgroundUnderstanding the interaction of graphene-related materials (GRM) with human cells is a key to the assessment of their potential risks for human health. There is a knowledge gap regarding the potential uptake of GRM by human intestinal cells after unintended ingestion. Therefore the aim of our study was to investigate the interaction of label-free graphene oxide (GO) with the intestinal cell line Caco-2 in vitro and to shed light on the influence of the cell phenotype given by the differentiation status on cellular uptake behaviour.ResultsInternalisation of two label-free GOs with different lateral size and thickness by undifferentiated and differentiated Caco-2 cells was analysed by scanning electron microscopy and transmission electron microscopy. Semi-quantification of cells associated with GRM was performed by flow cytometry. Undifferentiated Caco-2 cells showed significant amounts of cell-associated GRM, whereas differentiated Caco-2 cells exhibited low adhesion of GO sheets. Transmission electron microscopy analysis revealed internalisation of both applied GO (small and large) by undifferentiated Caco-2 cells. Even large GO sheets with lateral dimensions up to 10 µm, were found internalised by undifferentiated cells, presumably by macropinocytosis. In contrast, no GO uptake could be found for differentiated Caco-2 cells exhibiting an enterocyte-like morphology with apical brush border.ConclusionsOur results show that the internalisation of GO is highly dependent on the cell differentiation status of human intestinal cells. During differentiation Caco-2 cells undergo intense phenotypic changes which lead to a dramatic decrease in GRM internalisation. The results support the hypothesis that the cell surface topography of differentiated Caco-2 cells given by the brush border leads to low adhesion of GO sheets and sterical hindrance for material uptake. In addition, the mechanical properties of GRM, especially flexibility of the sheets, seem to be an important factor for internalisation of large GO sheets by epithelial cells. Our results highlight the importance of the choice of the in vitro model to enable better in vitro-in vivo translation.Electronic supplementary materialThe online version of this article (doi:10.1186/s12951-017-0280-7) contains supplementary material, which is available to authorized users.

show abstract

Toxicity of Graphene Oxide on Intestinal Bacteria and Caco-2 Cells

Cited by 48 publications

References 29 publications

Biotransformation and Biological Interaction of Graphene and Graphene Oxide during Simulated Oral Ingestion

Biotransformation and Biological Interaction of Graphene and Graphene Oxide during Simulated Oral Ingestion

Effect of co-existing kaolinite and goethite on the aggregation of graphene oxide in the aquatic environment

Uptake of label-free graphene oxide by Caco-2 cells is dependent on the cell differentiation status

Contact Info

Product

Resources

About