Fig. 1

(a) FTIR spectra of primary fibroin fibers, heat-treated fibroin, and mineralized fibers before and after heat treatment. (b) XRD spectra of primary and mineralized fibroin fibers before and after heat treatment. (c) Fourier self-deconvoluted (FSD) curve of native (unheated) fibroin fiber. (d) Fourier self-deconvoluted curve of heated fibroin fiber. (e) Curve deconvolution of non-heated mineralized fibroin (f) Curve deconvolution of heated mineralized fibroin. In the deconvoluted curves, the red solid curve is the deconvoluted spectrum, and the dotted curve shows the resultant amide I spectrum. In the FSD curves, the abbreviations stand for side chains (S), (BSS), β-sheets (B), random coil (R), α-helix (A), and turns (T).