Attenuated total reflection Fourier transform infrared spectroscopy analysis of human hair fiber structure.
The structure of human hair was studied by attenuated total reflection Fourier transform infrared (ATR-FT-IR) spectroscopy. The use of Ge, ZnSe, and Si internal reflection elements, various incident light angles, and difference spectra allowed detailed analysis of the cuticle, cortex, and cuticle-cortex intercellular regions without physically or mechanically removing the cuticle of the hair fiber. The ATR-FT-IR data showed the cuticle to be composed of protein having predominantly beta-sheet and disorder and beta-turn configurations. In contrast, the cortex spectra showed alpha-helical structures due to the presence of intermediate filaments of alpha keratin plus beta-sheet, beta-turn and disorder structures. In the cuticle-cortex interface region the protein structures were primarily disorder and beta-turn with small amounts of beta-sheet configurations. The spectral analyses are consistent with the general information on hair fiber structure proposed in the literature.
Lyman
Donald J
DJ
Department of Bioengineering, University of Utah, Salt Lake City, Utah 84112, USA. dlypr@comcast.net
Schofield
Paula
P
D002942:Circular Dichroism; D006197:Hair / Q000737:chemistry* / Q000648:ultrastructure*; D006801:Humans; D008855:Microscopy, Electron, Scanning; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D013055:Spectrophotometry, Infrared; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods