Anisotropical C₂−O reflection bands measured in α-helixes of silk fibroin

Abstract

From analysis of 36 anisotropical reflectrion spectra of the C₂−O bending bands of silk fibroin at ≈700∼200 cm⁻¹ region at static state, presence of the A, B, C and D-band and reflection edge was also confirmed. Furthermore, we confirmed stepnized reflectivity overlapping on the C₂−O bending bands and stenized values of the reflection integral (optical activity). Second, analysing four diffusion diagrams of these bands, we inspected stepnized polar distribution of the band and quantized polar distribution was confirmed as,

θ^N = 27.5·N + 2.5 (degrees) with N=1, 2, 3, 4...12 and 13, without N=5,6 and 7 at θ=120°∼180° as in case of polar distribution of the C₂−O and Si−O stretching reflection bands and C₂−O bending band measured in case of silicate cellulose present in the surface skin layer of bamboo's stem.