title: Structural characterization and artificial fiber formation of Bombyx mori silk fibroin in hexafluoro-iso-propanol solvent system.
abstract: High-resolution solution (13)C-NMR and CD studies of Bombyx mori silk fibroin revealed the presence of an ordered secondary structure 3(10)-helix, in hexafluoro-iso-propanol (HFIP). The solid-state structure of the silk fibroin film prepared by drying it gently from the HFIP solution still keep the structure, 3(10)-helix, which was studied with high-resolution solid state (13)C-NMR. The structural transition from the 3(10)-helix to silk II structure, heterogeneous structure including antiparallel beta-sheet, occurred during the artificial spinning from the HFIP solution. The wide-angle x-ray diffraction and differential scanning calorimetry thermograms of the artificial spinning fiber after postspinning treatments were observed together with the stress-strain curves. The results emphasize that the molecular structures, controlled morphology, and mechanical properties of the protein-based synthetic polymers can be modulated for enhancing biocompatibility.
authors.affiliation: Department of Biotechnology, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan.
authors.forename: Chenhua
authors.initials: C
authors.lastname: Zhao
authors.forename: Juming
authors.initials: J
authors.lastname: Yao
authors.forename: Hiromi
authors.initials: H
authors.lastname: Masuda
authors.forename: Raghuvansh
authors.initials: R
authors.lastname: Kishore
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Asakura
mesh_terms: D000818:Animals; D012831:Bombyx; D002152:Calorimetry, Differential Scanning; D002942:Circular Dichroism; D005349:Fibroins / Q000737:chemistry*; D006358:Hot Temperature; D019476:Insect Proteins / Q000737:chemistry*; D019906:Nuclear Magnetic Resonance, Biomolecular; D020005:Propanols / Q000737:chemistry*; D011487:Protein Conformation; D047011:Silk; D012997:Solvents; D013718:Tensile Strength; D014961:X-Ray Diffraction; D006845:Hydrocarbons, Fluorinated
chemical_list: D005349:Fibroins; D019476:Insect Proteins; D020005:Propanols; D047011:Silk; D012997:Solvents; C001337:hexafluoroisopropanol; D006845:Hydrocarbons, Fluorinated