Related Experiment Video
Updated: Aug 16, 2026

Synthesis of Keratin-based Nanofiber for Biomedical Engineering
Published on: February 7, 2016
Protein structural changes in keratin fibers induced by chemical modification using 2-iminothiolane hydrochloride: a
1Central Research Laboratories, Mandom Corp., 5-12, Juniken-cho, Chuo-ku, Osaka 540-8530, Japan. kuzuhara-a@mandom.co.jp
Abstract:
For the purpose of investigating in detail the influence of chemical modification using 2-iminothiolane hydrochloride (2-IT) on keratin fibers, the structure of cross-sections at various depths of white human hair, treated with 2-IT and then oxidized, was directly analyzed without isolating the cuticle and cortex, using Raman spectroscopy. In particular, the beta-sheet and/or random coil content (beta/R) and the alpha-helix (alpha) content in human hair fibers were estimated by amide I band analysis. The S-S band intensity, amide III (unordered) band intensity, and beta/R content existing from the cuticle region to the center of cortex region of virgin white human hair remarkably increased by performing the chemical modification using 2-IT. On the other hand, not only the S-S band intensity, but also S-O band intensity existing throughout the cortex region of the bleached (damaged) white human hair increased by performing chemical modification using 2-IT. In particular, beta/R content existing throughout the cortex region of the bleached white human hair decreased, while the skeletal C-C stretch (alpha) band intensity at 935 cm(-1) and the alpha content remarkably increased. This indicates a secondary structural change from the random coil form to the alpha-helix form in the proteins existing throughout the cortex region. From these experiments, we concluded that the formation of new disulfide (-SS-) groups resulting from chemical modification using 2-IT induced the secondary structural changes of proteins existing throughout the cortex region.
More Related Videos
Related Concept Videos
Disassembly of Intermediate Filaments
Keratin proteins, found at the cell periphery near cell junctions, undergo a cycle of assembly and disassembly. In Type...
Spectroscopy of Carboxylic Acid Derivatives
In the...
Structure and Nomenclature of Thiols and Sulfides
Aldehydes and Ketones with Amines: Imine and Enamine Formation Overview
Mass Spectrometry of Amines

