An evaluation of cell proliferation and adhesion on vertically-aligned multi-walled carbon nanotube films

Biocompatibility tests were performed on vertically-aligned multi-walled carbon nanotube (MWCNT) films produced by microwave plasma chemical vapor deposition on titanium substrates with iron (Fe) and nickel (Ni) as catalysts. The cell adhesion and morphology of L-929 mouse fibroblast cells were studied by high resolution scanning electron microscopy, after up to 7 days incubation periods. Cell viability and proliferation were evaluated by two “in vitro” tests: (1) 2-(4,5-dimethyl-2-thiazolyl)-3,5-diphenyl-2H-tetrazolium bromide (MTT), and (2) lactate dehydrogenase (LDH) assays. Low level of bioavailable Fe and Ni was determined by inductively coupled plasma optical emission spectrometry. Neither functionalization nor purification of MWCNT films was necessary to obtain good response to the biocompatibility tests. Efficient cell growth and non-toxicity suggest the use MWCNTs in tissue regeneration. The MWCNT films stimulated the cell growth, showing a proliferation 20% higher than on Ti.