title: Minerals and aligned collagen fibrils in tilapia fish scales: structural analysis using dark-field and energy-filtered transmission electron microscopy and electron tomography.
abstract: The mineralized structure of aligned collagen fibrils in a tilapia fish scale was investigated using transmission electron microscopy (TEM) techniques after a thin sample was prepared using aqueous techniques. Electron diffraction and electron energy loss spectroscopy data indicated that a mineralized internal layer consisting of aligned collagen fibrils contains hydroxyapatite crystals. Bright-field imaging, dark-field imaging, and energy-filtered TEM showed that the hydroxyapatite was mainly distributed in the hole zones of the aligned collagen fibrils structure, while needle-like materials composed of calcium compounds including hydroxyapatite existed in the mineralized internal layer. Dark-field imaging and three-dimensional observation using electron tomography revealed that hydroxyapatite and needle-like materials were mainly found in the matrix between the collagen fibrils. It was observed that hydroxyapatite and needle-like materials were preferentially distributed on the surface of the hole zones in the aligned collagen fibrils structure and in the matrix between the collagen fibrils in the mineralized internal layer of the scale.
authors: Biomaterials Center, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan.
authors: Mitsuhiro
authors: M
authors: Okuda
authors: Nobuhiro
authors: N
authors: Ogawa
authors: Masaki
authors: M
authors: Takeguchi
authors: Ayako
authors: A
authors: Hashimoto
authors: Motohiro
authors: M
authors: Tagaya
authors: Song
authors: S
authors: Chen
authors: Nobutaka
authors: N
authors: Hanagata
authors: Toshiyuki
authors: T
authors: Ikoma
mesh_terms: D000818:Animals; D003094:Collagen / Q000648:ultrastructure*; D055032:Electron Microscope Tomography; D034582:Integumentary System; D046032:Microscopy, Energy-Filtering Transmission Electron; D008903:Minerals / Q000032:analysis*; D017210:Tilapia
chemical_list: D008903:Minerals; D003094:Collagen