Effect of Functionalized Carbon Nanotubes and their Citric Acid Polymerization on Mesenchymal Stem Cells In Vitro

Figure 7

Confocal microscope images of the MSC cells incubated during 72 hours in the 100 ng/ml solution for each type of nanotube. (a) Control sample showing the red fluorescence field (at 488 nm) where the nuclei morphology is unaffected (i), the green fluorescence (at 633 nm) of CNTs with no trace of them (ii), the match of (i) and (ii) in (iii), and the bright field of the sample (iv). White arrows in panels (b–e) show the intracellular distribution of fMWNTs (b), PMWNTs (c), fCNxs (d), and PCNxs (e). Panels (i) show the red fluorescence field, illustrating the nuclei morphology; the white circles in (b, i) and (d, i) show apoptotic nuclei. Panels (ii) show green fluorescence of CNTs with clear nanotube presence in the fMWNT and fCNx samples (b, ii) and (d, ii), respectively. Panels (iii) show the match of (i) and (ii). Panels (iv) show the bright field where fMWNTs and fCNxs clearly present the fibrillar structure of the CNTs inside the MSCs.

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