title: Preparation and characterization of multilayered hydroxyapatite/silk fibroin film.
abstract: We prepared multilayered films consisting of silk fibroin (SF) and hydroxyapatite (HAp) by alternating lamination using untreated SF and HAp-deposited SF films. Untreated SF films were prepared from a regenerated SF solution by air drying. HAp-deposited SF films were prepared by soaking methanol-treated SF films containing >5 wt% CaCl2 in a simulated body fluid with the ion concentration 1.5-fold higher than that of the standard one. The multilayered HAp/SF films had HAp layers with approximate thicknesses of 3-5 microm and SF layers with thicknesses of 40-70 microm. The bonding strength between the SF and HAp layers was significantly affected by temperature and compression time under the lamination method. The optimal conditions for achieving the maximum T-peel strength and beta-sheet contents were determined to be 130 degrees C for 4 min. The Young's modulus of the multilayered films (133.4 MPa) was higher than that of the films consisting of SF alone (92.5 MPa) under swollen conditions. The biocompatibility of the HAp-deposited SF films was analyzed by culturing of osteoblasts (MC3T3-E1) on a film. The results indicate that HAp-deposited SF films and SF films show similar degrees of cell adhesion and alkaline phosphatase activities.
authors.affiliation: Faculty and Graduate School of Engineering, Hokkaido University, Kita 13, Nishi 9, Kita-ku, Sapporo, Hokkaido 060-8628, Japan. kino@cris.hokudai.ac.jp
authors.forename: Rikako
authors.initials: R
authors.lastname: Kino
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Ikoma
authors.forename: Shunji
authors.initials: S
authors.lastname: Yunoki
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Nagai
authors.forename: Junzo
authors.initials: J
authors.lastname: Tanaka
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Asakura
authors.forename: Masanobu
authors.initials: M
authors.lastname: Munekata
mesh_terms: D016475:3T3 Cells; D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry* / Q000302:isolation & purification; D001696:Biomechanical Phenomena; D012831:Bombyx / Q000737:chemistry; D002448:Cell Adhesion; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D017886:Durapatite / Q000737:chemistry*; D005349:Fibroins / Q000737:chemistry*; D048091:Guided Tissue Regeneration; D008567:Membranes, Artificial; D051379:Mice; D008855:Microscopy, Electron, Scanning; D047011:Silk / Q000737:chemistry*; D013718:Tensile Strength
chemical_list: D001672:Biocompatible Materials; D020099:Coated Materials, Biocompatible; D008567:Membranes, Artificial; D047011:Silk; C482288:fibroin, silkworm; D005349:Fibroins; D017886:Durapatite; D000469:Alkaline Phosphatase