title: Use of precisely sculptured thin film (STF) substrates with generalized ellipsometry to determine spatial distribution of adsorbed fibronectin to nanostructured columnar topographies and effect on cell adhesion.
abstract: Sculptured thin film (STF) substrates consist of nanocolumns with precise orientation, intercolumnar spacing, and optical anisotropy, which can be used as model biomaterial substrates to study the effect of homogenous nanotopogrophies on the three-dimensional distribution of adsorbed proteins. Generalized ellipsometry was used to discriminate between the distributions of adsorbed FN either on top of or within the intercolumnar void spaces of STFs, afforded by the optical properties of these precisely crafted substrates. Generalized ellipsometry indicated that STFs with vertical nanocolumns enhanced total FN adsorption two-fold relative to flat control substrates and the FN adsorption studies demonstrate different STF characteristics influence the degree of FN immobilization both on top and within intercolumnar spaces, with increasing spacing and surface area enhancing total protein adsorption. Mouse fibroblasts or mouse mesenchymal stem cells were subsequently cultured on STFs, to investigate the effect of highly ordered and defined nanotopographies on cell adhesion, spreading, and proliferation. All STF nanotopographies investigated in the absence of adsorbed FN were found to significantly enhance cell adhesion relative to flat substrates; and the addition of FN to STFs was found to have cell-dependent effects on enhancing cell-material interactions. Furthermore, the amount of FN adsorbed to the STFs did not correlate with comparative enhancements of cell-material interactions, suggesting that nanotopography predominantly contributes to the biocompatibility of homogenous nanocolumnar surfaces. This is the first study to correlate precisely defined nanostructured features with protein distribution and cell-nanomaterial interactions. STFs demonstrate immense potential as biomaterial surfaces for applications in tissue engineering, drug delivery, and biosensing.
authors.affiliation: Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588, USA; Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, Lincoln, NE 68588, USA.
authors.forename: Tadas
authors.initials: T
authors.lastname: Kasputis
authors.affiliation: Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588, USA; Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, Lincoln, NE 68588, USA.
authors.forename: Alex
authors.initials: A
authors.lastname: Pieper
authors.affiliation: Department of Electrical Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588, USA; Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, Lincoln, NE 68588, USA.
authors.forename: Keith Brian
authors.initials: KB
authors.lastname: Rodenhausen
authors.affiliation: Department of Electrical Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588, USA; Singapore Synchotron Light Source, National University of Singapore, 119077, Singapore; Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, Lincoln, NE 68588, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Schmidt
authors.affiliation: Department of Electrical Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588, USA; Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, Lincoln, NE 68588, USA.
authors.forename: Derek
authors.initials: D
authors.lastname: Sekora
authors.affiliation: Department of Electrical Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588, USA; Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, Lincoln, NE 68588, USA.
authors.forename: Charles
authors.initials: C
authors.lastname: Rice
authors.affiliation: Department of Electrical Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588, USA; Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, Lincoln, NE 68588, USA.
authors.forename: Eva
authors.initials: E
authors.lastname: Schubert
authors.affiliation: Department of Electrical Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588, USA; Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE 68588, USA; Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, Lincoln, NE 68588, USA.
authors.forename: Mathias
authors.initials: M
authors.lastname: Schubert
authors.affiliation: Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588, USA; Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE 68588, USA; Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, Lincoln, NE 68588, USA; Mary and Dick Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, NE 68198, USA. Electronic address: apannier2@unl.edu.
authors.forename: Angela K
authors.initials: AK
authors.lastname: Pannier
mesh_terms: D000327:Adsorption; D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology; D002448:Cell Adhesion / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D005347:Fibroblasts / Q000166:cytology* / Q000187:drug effects; D005353:Fibronectins / Q000494:pharmacology*; D006801:Humans; D051379:Mice; D008856:Microscopy, Fluorescence; D041681:NIH 3T3 Cells; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D058525:Quartz Crystal Microbalance Techniques
chemical_list: D001672:Biocompatible Materials; D005353:Fibronectins
keywords: Biocompatibility; Cell adhesion; Nanotopography; Protein adsorption; Surface analysis