title: Wet-spinning of recombinant silk-elastin-like protein polymer fibers with high tensile strength and high deformability.
abstract: A recombinant silk-elastin-like protein copolymer SELP-47K containing tandemly repeated amino acid sequence blocks from silk, GAGAGS, and elastin, GVGVP, was fabricated into microdiameter fibers using a wet-spinning technique. Raman spectral analysis revealed the formation of antiparallel beta-sheet crystals of the silk-like blocks. Dry SELP-47K fibers display the dependence of mechanical properties such as Young's modulus on fiber diameter, suggesting more oriented and crystallized molecular chains in small-diameter fibers. Additionally, a brittle fracture mode was identified for dry fibers by SEM analysis of fracture surfaces. Hydration dramatically influenced the mechanical behavior of SELP-47K fibers. In contrast to the high tensile strength and limited strains to failure of dry fibers, fully hydrated SELP-47K fibers possessed strains to failure as high as 700%. Furthermore, upon chemical cross-linking, a tensile mechanical strength up to 20 MPa was achieved in hydrated fibers without compromising their high deformability. By combing the silk- and elastin-derived sequences into a single SELP-47K protein polymer, we demonstrated that protein fibers with high tensile strength and high deformability can be fabricated.
authors.affiliation: Department of Aerospace and Mechanical Engineering, University of Arizona, Tucson, Arizona 85721, USA.
authors.forename: Weiguo
authors.initials: W
authors.lastname: Qiu
authors.forename: Weibing
authors.initials: W
authors.lastname: Teng
authors.forename: Joseph
authors.initials: J
authors.lastname: Cappello
authors.forename: Xiaoyi
authors.initials: X
authors.lastname: Wu
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry; D001704:Biopolymers / Q000737:chemistry*; D004549:Elastin / Q000737:chemistry*; D006860:Hydrogen Bonding; D046911:Macromolecular Substances / Q000138:chemical synthesis / Q000737:chemistry; D008567:Membranes, Artificial; D015394:Molecular Structure; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D018583:Pliability; D011994:Recombinant Proteins / Q000138:chemical synthesis / Q000737:chemistry; D047011:Silk / Q000737:chemistry*; D013499:Surface Properties; D013718:Tensile Strength; D014867:Water / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D001704:Biopolymers; D046911:Macromolecular Substances; D008567:Membranes, Artificial; D011994:Recombinant Proteins; D047011:Silk; D014867:Water; D004549:Elastin