title: Tunable chemistry and morphology of multi-wall carbon nanotubes as a route to non-toxic, theranostic systems.
abstract: Nanomedicine is one of the most promising areas of exploitation for multi-walled carbon nanotubes (MWNTs). These 'needle-like' nanovehicles are capable of carrying drug molecules via exo- and endohedral functionalisation and are steerable by an external magnetic field due to the presence of ferromagnetic nanoparticles in the nanotube core (up to 7.3wt.%). These properties make them promising candidates for drug targeting or MRI contrast agents. Particularly, oxidised and nitrogen-doped MWNTs exhibiting enhanced chemical reactivity compared to their unmodified precursors/analogues could be exploited in this field. Here, we assessed the toxicity and intracellular localisation of two different, chemically modified and unmodified nanotubes towards human macrophage cells using a range of toxicity and imaging techniques. Oxidised and N-doped MWNTs were not significantly toxic to HMMs in contrast to unmodified MWNTs. All types of MWNTs entered the cell via active phagocytosis/endocytosis, but also passively by 'self-injection' through the plasma membrane, and were ultimately found in the cytoplasm and possibly also the nucleus. The attained results carry hope to utilise functionalised nanotube vectors as non-cytotoxic controllable drug delivery systems.
authors.affiliation: Department of Organic Chemistry, Biochemistry and Biotechnology, Silesian University of Technology, Krzywoustego 4, Gliwice 44-100, Poland. slawomir.boncel@polsl.pl
authors.forename: Sławomir
authors.initials: S
authors.lastname: Boncel
authors.forename: Karin H
authors.initials: KH
authors.lastname: Müller
authors.forename: Jeremy N
authors.initials: JN
authors.lastname: Skepper
authors.forename: Krzysztof Z
authors.initials: KZ
authors.lastname: Walczak
authors.forename: Krzysztof K K
authors.initials: KK
authors.lastname: Koziol
mesh_terms: D002463:Cell Membrane Permeability; D002470:Cell Survival; D002478:Cells, Cultured; D006801:Humans; D008264:Macrophages / Q000166:cytology* / Q000378:metabolism; D037742:Nanotubes, Carbon / Q000032:analysis* / Q000737:chemistry / Q000633:toxicity* / Q000648:ultrastructure; D009584:Nitrogen / Q000737:chemistry / Q000633:toxicity; D010084:Oxidation-Reduction
chemical_list: D037742:Nanotubes, Carbon; D009584:Nitrogen