Fig. 3: Characterization of the β-sheet formation of MaSp2 fiber formed in the microfluidic device or by manual drawing.
From: Replicating shear-mediated self-assembly of spider silk through microfluidics
a Secondary structure of the MaSp2 fiber determined by Raman spectroscopy immediately after fiber assembly inside the channel. b Negative control experiment of N-R12-C and N-R12-C(xA) outside the microfluidic device. N-R12-C and N-R12-C(xA) were gently mixed with 1 M CPB at pH 5 and 7 on a cover slide at a 1:1 volume ratio. A positive control was conducted by immersing N-R12-C nanofibrils in 90% methanol (MeOH) solution for 5 min after removal of 1 M CPB (pH 5). The dash line denotes the peak at 1654 cm−1. c Comparison of N-R6-C, N-R12-C and N-R12-C(xA) in three sections along the channel. Peak features were specifically evaluated within the amide I region. d Raman results of N-R12-C fiber under various negative pressures. The solid line denotes the peak at 1664 cm−1. e β-sheet contents of N-R12-C fiber assembled inside the microfluidic device under various negative pressures. Peak fitting was carried out to calculate the β-sheet contents after deconvolution within the amide I region. Data are presented as mean values ± SD; n = 3. f Comparison of Raman signals for N-R6-C, N-R12-C and N-R12-C(xA) fibers formed by biomimetic spinning and manual drawing. Source data are provided as a Source Data file.
