title: Supercritical CO2-assisted embossing for studying cell behaviour on microtextured surfaces.
abstract: Recently, cell responses to micro- and nanoscale structures have attracted much attention. Although interesting phenomena have been observed, we have encountered some difficulties in elucidating purely topographical effects on cell behaviour. These problems are partially attributable to the introduction of functional groups and the persistence of chemicals during surface processing. In this study, we introduced supercritical CO(2)-assisted embossing, which plasticizes a polycarbonate plate by dissolving supercritical CO(2) and thus can emboss wide-scale patterns onto the plate at a lower temperature than the polycarbonate glass transition temperature. Uniform micro- and nanopatterned surfaces were observed across the whole area of the polycarbonate plate surfaces. Nickel, fluorine, and nitrogen were not detected on the fabricated surfaces, and the surface carbon-to-oxygen ratios were equivalent to the theoretical ratio (C:O=84.2:15.8) calculated from the polycarbonate molecular structure. Human mesenchymal stem cells were cultured on the fabricated microlens and nanogroove substrata. Cell-adhered areas became smaller on the microlens than on non-treated polycarbonate. Meanwhile, cells aligned along the ridges of nanogrooves with valleys deeper than 90 nm. This supercritical CO(2)-assisted embossing can produce fine substrates for studying the effects of surface topography of synthetic materials on cell behaviours.
authors.affiliation: Department of Reparative Materials, Institute for Frontier Medical Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Fujita
authors.forename: Daizaburo
authors.initials: D
authors.lastname: Ono
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ohshima
authors.forename: Hiroo
authors.initials: H
authors.lastname: Iwata
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry*; D002448:Cell Adhesion; D018929:Cell Culture Techniques / Q000379:methods*; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D011076:Polycarboxylate Cement / Q000737:chemistry; D013499:Surface Properties
chemical_list: D001672:Biocompatible Materials; D011076:Polycarboxylate Cement; D002245:Carbon Dioxide; C005506:polycarbonate