title: Study of neuron survival on polypyrrole-embedded single-walled carbon nanotube substrates for long-term growth conditions.
abstract: Cultures of primary embryonic rat brain hippocampus neurons with supporting glia cells were carried out on different substrates containing polypyrrole (PPy) and/or single-walled carbon nanotubes (SWCNTs). Neuron adhesion, neurites and dendrites branching elongation, and development of neuron networks on substrates were followed by phase-contrast optical microscopy and quantified to state cell survival and proliferation. Suspensions of as-grown and purified SWCNTs were sprayed on a glass coverslips and PPy/SWCNTs were deposited by potentiodynamic electrochemical deposition. Cell neurotoxicity revealed by neuron death was very high for purified SWCNTs substrates in good agreement with [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) test showing lower viability on SWCNTs containing substrates compared with PPy-substrates and control samples probably due to the metal content and the carboxylic groups introduced during the purification. It is interesting to highlight that neurons grown on PPy-substrates adhere developing neurites and branching dendrites earlier even than on control cultures. On subsequent days the neurons are able to adapt to nanotube substrates developing neuron networks for 14-day cultures with similar patterns of complexity for control, PPy and PPy/SWCNT substrates. PPy/SWCNT substrates show a lower impedance value at frequencies under 1 Hz. We have come to the conclusion that glia cells and PPy added to the culture medium and substrates respectively, improve in some degree nanotube biocompatibility, cell adhesion and hence cell viability.
authors.affiliation: Instituto de Carboquímica (CSIC), C/ Miguel Luesma Castán 4, E-50018, Zaragoza, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Hernández-Ferrer
authors.forename: Rodolfo N
authors.initials: RN
authors.lastname: Pérez-Bruzón
authors.forename: María J
authors.initials: MJ
authors.lastname: Azanza
authors.forename: Mónica
authors.initials: M
authors.lastname: González
authors.forename: Raquel
authors.initials: R
authors.lastname: Del Moral
authors.forename: Alejandro
authors.initials: A
authors.lastname: Ansón-Casaos
authors.forename: Jesús M
authors.initials: JM
authors.lastname: de la Fuente
authors.forename: Pedro C
authors.initials: PC
authors.lastname: Marijuan
authors.forename: M Teresa
authors.initials: MT
authors.lastname: Martínez
mesh_terms: D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D018929:Cell Culture Techniques; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism*; D008422:Materials Testing; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009457:Neuroglia / Q000166:cytology / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D011108:Polymers / Q000737:chemistry / Q000494:pharmacology; D011758:Pyrroles / Q000737:chemistry / Q000494:pharmacology; D051381:Rats; D013997:Time Factors
chemical_list: D037742:Nanotubes, Carbon; D011108:Polymers; D011758:Pyrroles; C067635:polypyrrole
keywords: cytotoxicity; long-term growth conditions; neural growth; polypyrrole electrodeposition; single-walled carbon nanotubes