title: Synchrotron FTIR microspectroscopy of single natural silk fibers.
abstract: Synchrotron FTIR (S-FTIR) microspectroscopy was used to monitor the silk protein conformation in a range of single natural silk fibers (domestic and wild silkworm and spider dragline silk). With the selection of suitable aperture size, we obtained high-resolution S-FTIR spectra capable of semiquantitative analysis of protein secondary structures. For the first time, we have determined from S-FTIR the β-sheet content in a range of natural single silk fibers, 28 ± 4, 23 ± 2, and 17 ± 4% in Bombyx mori, Antheraea pernyi, and Nephila edulis silks, respectively. The trend of β-sheet content in different silk fibers from the current study accords quite well with published data determined by XRD, Raman, and (13)C NMR. Our results indicate that the S-FTIR microspectroscopy method has considerable potential for the study of single natural silk fibers.
authors.affiliation: The Key Laboratory of Molecular Engineering of Polymers of MOE, Department of Macromolecular Science, Laboratory of Advanced Materials, Fudan University, Shanghai, 200433, China.
authors.forename: Shengjie
authors.initials: S
authors.lastname: Ling
authors.forename: Zeming
authors.initials: Z
authors.lastname: Qi
authors.forename: David P
authors.initials: DP
authors.lastname: Knight
authors.forename: Zhengzhong
authors.initials: Z
authors.lastname: Shao
authors.forename: Xin
authors.initials: X
authors.lastname: Chen
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000032:analysis / Q000737:chemistry*; D012831:Bombyx / Q000737:chemistry*; D005349:Fibroins / Q000032:analysis / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D017433:Protein Structure, Secondary; D047011:Silk / Q000032:analysis / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*; D013059:Spectrum Analysis, Raman; D013112:Spiders / Q000737:chemistry*; D017356:Synchrotrons
chemical_list: D001672:Biocompatible Materials; D047011:Silk; D005349:Fibroins