title: Co-cross-linking silk matrices with silica nanostructures for robust ultrathin nanocomposites.
abstract: We report on a novel assembly approach to fabricate ultrathin robust freely standing nanocomposite membranes. The materials are composed of a pre-cross-linked silk fibroin matrix with incorporated silica nanoparticles with silsesquioxane cores (POSS) or clay nanoplatelets. These reinforced silk membranes have enhanced mechanical properties as compared to traditional silk-based nanocomposites reported previously. Up to 6-fold and 8-fold increase in elastic modulus and toughness, respectively, were found for these nanocomposites. In contrast, traditional LbL-assembled nanocomposites showed only a 3-fold increase in mechanical strength. The silk nanocomposites obtained also revealed excellent optical transparency in the visible region especially if reinforced with POSS nanoparticles, which suggests their utility as low cost, nontoxic, and easily scalable reinforced biomaterials for mechanically demanding applications.
authors.affiliation: School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
authors.forename: Eugenia
authors.initials: E
authors.lastname: Kharlampieva
authors.forename: Veronika
authors.initials: V
authors.lastname: Kozlovskaya
authors.forename: Brett
authors.initials: B
authors.lastname: Wallet
authors.forename: Valeriy V
authors.initials: VV
authors.lastname: Shevchenko
authors.forename: Rajesh R
authors.initials: RR
authors.lastname: Naik
authors.forename: Richard
authors.initials: R
authors.lastname: Vaia
authors.forename: David L
authors.initials: DL
authors.lastname: Kaplan
authors.forename: Vladimir V
authors.initials: VV
authors.lastname: Tsukruk
mesh_terms: D003432:Cross-Linking Reagents / Q000737:chemistry*; D005349:Fibroins / Q000737:chemistry*; D005976:Glutaral / Q000737:chemistry; D055595:Mechanical Phenomena; D008567:Membranes, Artificial; D053761:Nanocomposites / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D055620:Optical Phenomena; D012822:Silicon Dioxide / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties
chemical_list: D003432:Cross-Linking Reagents; D008567:Membranes, Artificial; D012822:Silicon Dioxide; D005349:Fibroins; D005976:Glutaral