Page 12 - MODCOMP Newsletter no 4

Newsletter, Volume 4

Cytotoxicity assessment of carbon nanotubes

NTUA in collaboration with IRES successfully accomplished D5.1: Release and Exposure Assessment, in
September 2018. One of the goals of this study was the evaluation of the potential cytotoxic effect of
multiwalled carbon nanotubes (MWCNTs) either in their pristine form (not functionalized) or after their
functionalisation with oxygen containing groups, by applying the instructions and protocols reported in
the ISO 10993-5. Cell attachment and cell morphology was assessed through SEM. SEM micrographs
revealed a firm interaction between the cultured cells’ surface and the MWCNTs. Both in the case of not
functionalized and functionalized MWCNTs the cells’ morphology appeared altered and distorted
compared to the morphology of the cells in the control sample, thus indicating that the presence of
MWCNTs negatively affect cells viability. It is evident that MWCNTs established unyielding contacts with
the cellular membrane and as the time that cells remained in contact with MWCNTs increased, the
cellular membrane started to break down, suggesting that cells will initiate their apoptotic process. In
the case of not functionalized MWCNTs this effect was milder, which can be attributed to the absence
of the carboxylic groups (present in functionalized MWCNTs).

SEM micrographs showing cells morphology in contact for 3 hours with a suspension of 50 µg/ml of (a) not functionalized
MWCNTs and (b) functionalized MWCNTs

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