title: Sub-nm 3D observation of human hair melanin by high-voltage STEM.
abstract: The ultrastructure of melanin granules in human hair was studied using 1,000 kV high-voltage scanning transmission electron microscopy to successfully reconstruct three-dimensional images of the whole melanin granule. It was revealed that the melanin granule was composed of a membrane-like outer structure that included many spherical vesicles, and an inner matrix containing a sheet-like structure in the elongated direction of the melanin granule and a sheet-like arrays structure in the cross direction. The outer structure of the melanin granule was maintained even after exposure to hair-bleaching agents to decompose the melanin granule, suggesting that the outer structure was a highly robust structure and composition compared with the inner matrix .
authors.affiliation: General Research and Development Institute, Hoyu Co., Ltd., 1-12, Roboku, Nagakute-city, Aichi 480-1131, Japan Department of Anatomy, Aichi Medical University School of Medicine, 21, Karimata, Yazako, Nagakute-city, Aichi 480-1195, Japan Takehito_Imai@hoyu.co.jp.
authors.forename: Takehito
authors.initials: T
authors.lastname: Imai
authors.affiliation: High Voltage Electron Microscope Laboratory, Nagoya University, Nagoya, Aichi 464-8603, Japan.
authors.forename: Kimitaka
authors.initials: K
authors.lastname: Higuchi
authors.affiliation: High Voltage Electron Microscope Laboratory, Nagoya University, Nagoya, Aichi 464-8603, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Yamamoto
authors.affiliation: High Voltage Electron Microscope Laboratory, Nagoya University, Nagoya, Aichi 464-8603, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Arai
authors.affiliation: Department of Anatomy, Aichi Medical University School of Medicine, 21, Karimata, Yazako, Nagakute-city, Aichi 480-1195, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakano
authors.affiliation: High Voltage Electron Microscope Laboratory, Nagoya University, Nagoya, Aichi 464-8603, Japan.
authors.forename: Nobuo
authors.initials: N
authors.lastname: Tanaka
mesh_terms: D044466:Asian People; D006197:Hair / Q000648:ultrastructure*; D058206:Hair Bleaching Agents; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D007564:Japan; D008543:Melanins / Q000032:analysis*; D017348:Microscopy, Electron, Scanning Transmission / Q000379:methods*
chemical_list: D058206:Hair Bleaching Agents; D008543:Melanins
keywords: 3D structure; hair lightener; high-voltage electron microscope; human hair; melanin granule; scanning transmission electron microscope