Characterizing Wool Keratin

Figure 3

Peak area, %, of resolved amide and sulfoxide bands in keratin preparations: samples 1 to 4, (a) amide region: Amide I (1680 and 1645 cm⁻¹), Amide II (1550 and 1515 cm⁻¹), and Amide III (1435 cm⁻¹); (b) sulfoxide regions: Bunte-salt, Cysteine-S-sulfonate; Cy-S-SO⁻³ (1012 cm⁻¹), Cysteic acid, CySO₃H (1045 cm⁻¹), Cystine-Smonoxide, Cy-SO-S-Cy (1080 cm⁻¹), and Cystine-Sdioxide, CySO₂-S-Cy (1137 cm⁻¹).

(a)

(b)