Fig. 2: Secondary structure, SEM, and water sorption isotherms of the RSF samples.
From: The role of water mobility on water-responsive actuation of silk
a Normalized ATR-FTIR spectra of Amide I (1650/cm peak) and II (1520/cm peak) bands and the deconvolution peaks for Silk-H, Silk-M, and Silk-L samples. The deconvolution peaks are centered at 1510/cm (β-sheet), 1530/cm (Random coil), 1540/cm (α-helix), 1565/cm (β-turn) for Amide II peak, 1592/cm (baseline correction—see “Methods” section), and 1620/cm (β-sheet—inter-/intra-molecular), 1640/cm (α-helix), 1655/cm (Random Coil), 1680 (β-turn), 1695/cm (β-sheet—intermolecular) for Amide I peak. b Crystalline and amorphous fractions of Silk-H, Silk-M, and Silk-L were determined from the areas of the deconvolution peaks of the Amide I peak. c SEM images of cryo-fractured cross-sections of RSF films. The scale bars in the upper and lower images are 1 µm and 3 µm, respectively. d Relative mass change as a function of RH measured by DVS. Data are presented as mean ± SD (n = 3 hydration/dehydration cycles).
