. Author manuscript; available in PMC: 2013 Apr 1.

Published in final edited form as: Acta Biomater. 2011 Dec 16;8(4):1530–1542. doi: 10.1016/j.actbio.2011.12.015

Table 1.

Vibrational band assignments for the amide I region of silk fibroin [45, 49].

Wavenumber range (cm⁻¹)	Secondary structure assignment
1,605–1,615	(Tyr) side chains/aggregated strands
1,616–1,621	Aggregate β-strand/sheet (weak)^a
1,622–1,627	β-Sheets (strong)^a
1,628–1,637	β-Sheets (strong)^b
1,638–1,646	Random coils/extended chains
1,647–1,655	Random coils
1,656–1,662	α-Helix
1,663–1,670	Turns
1,671–1,670	Turns
1,671–1,685	Turns
1,686–1,695	Turns
1,697–1,703	β-Sheets (weak)^a

Intermolecular β-sheets;

Intramolecular β-sheets