title: Synthesis of thiolated polysaccharides for formation of polyelectrolyte multilayers with improved cellular adhesion.
abstract: Intrinsic cross-linking is not only useful for increasing stability, but also for tailoring mechanical properties of polyelectrolyte multilayers (PEM) on implants and tissue engineering scaffolds. Here, a novel route for synthesizing thiolated chitosan (t-Chi) based on the application of 3,3'-dithiodipropionic acid was applied, while thiolated chondroitin sulfate (t-CS) was conjugated by 3,3'-dithiobis (propanoic hydrazide). Both products were subsequently reduced to obtain the free thiols. The thiol content, structural changes and degree of substitution were studied by UV-vis, FTIR, Raman and1H NMR spectroscopy, respectively. Chi and CS can be used for PEM formation with the layer-by-layer method, due to the cationic nature of Chi at pH values below 5.0 and the anionic character of CS. Comparative studies on the formation of native Chi/CS versus t-Chi/t-CS PEM with surface plasmon resonance and ellipsometry revealed higher layer mass. We also found that the PEM composed of t-Chi/t-CS had superior cell adhesion properties for human keratinocytes in comparison to the native PEM.
authors.affiliation: Biomedical Materials Group, Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Heinrich-Damerow-Strasse 4, D-06120 Halle (Saale), Germany; Interdisciplinary Center for Material Research & Institute of Physics, Martin Luther University Halle-Wittenberg, Heinrich-Damerow-Strasse 4, 06120 Halle (Saale), Germany.
authors.forename: Pegah
authors.initials: P
authors.lastname: Esmaeilzadeh
authors.affiliation: Biomedical Materials Group, Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Heinrich-Damerow-Strasse 4, D-06120 Halle (Saale), Germany; Interdisciplinary Center for Material Research & Institute of Physics, Martin Luther University Halle-Wittenberg, Heinrich-Damerow-Strasse 4, 06120 Halle (Saale), Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Köwitsch
authors.affiliation: Interdisciplinary Center for Material Research & Institute of Physics, Martin Luther University Halle-Wittenberg, Heinrich-Damerow-Strasse 4, 06120 Halle (Saale), Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Heyroth
authors.affiliation: Interdisciplinary Center for Material Research & Institute of Physics, Martin Luther University Halle-Wittenberg, Heinrich-Damerow-Strasse 4, 06120 Halle (Saale), Germany.
authors.forename: Georg
authors.initials: G
authors.lastname: Schmidt
authors.affiliation: Institute of Plant and Wood Chemistry, Dresden University of Technology, Pienner Strasse 19, D-01737 Tharandt, Germany.
authors.forename: Steffen
authors.initials: S
authors.lastname: Fischer
authors.affiliation: Heppe Medical Chitosan GmbH, Heinrich-Damerow-Strasse 1, 06120 Halle, Germany.
authors.forename: Katja
authors.initials: K
authors.lastname: Richter
authors.affiliation: Biomedical Materials Group, Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Heinrich-Damerow-Strasse 4, D-06120 Halle (Saale), Germany; Interdisciplinary Center for Material Research & Institute of Physics, Martin Luther University Halle-Wittenberg, Heinrich-Damerow-Strasse 4, 06120 Halle (Saale), Germany. Electronic address: thomas.groth@pharmazie.uni-halle.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Groth
mesh_terms: D002448:Cell Adhesion; D002478:Cells, Cultured; D048271:Chitosan / Q000737:chemistry*; D006801:Humans; D015603:Keratinocytes / Q000166:cytology*; D000071228:Polyelectrolytes / Q000737:chemistry*; D054457:Tissue Scaffolds
chemical_list: D000071228:Polyelectrolytes; D048271:Chitosan
keywords: Bioactive coatings; Cell adhesion; Layer-by-layer technique; Polysaccharides; Thiolated chitosan; Thiolated chondroitin sulfate