Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, Crawley, Perth, WA 6009, Australia.
Microsc Microanal. 2011 Apr;17(2):220-5. doi: 10.1017/S1431927610094547. Epub 2011 Mar 4.
The teeth of the marine mollusk Acanthopleura hirtosa are an excellent example of a complex, organic, matrix-mediated biomineral, with the fully mineralized teeth comprising layers of iron oxide and iron oxyhydroxide minerals around a calcium apatite core. To investigate the relationship between the various mineral layers and the organic matrix fibers on which they grew, sections have been prepared from specific features in the teeth at controlled orientations using focused ion beam processing. Compositional and microstructural details of heterophase interfaces, and the fate of the organic matrix fibers within the mineral layers, can then be analyzed by a range of transmission electron microscopy (TEM) techniques. Energy-filtered TEM highlights the interlocking nature of the various mineral phases, while high-angle annular dark-field scanning TEM imaging demonstrates that the organic matrix continues to exist in the fully mineralized teeth. These new insights into the structure of this complex biomaterial are an important step in understanding the relationship between its structural and physical properties and may help explain its high strength and crack-resistance behavior.
海洋软体动物 Acanthopleura hirtosa 的牙齿是复杂的有机基质介导生物矿化的极好范例，完全矿化的牙齿由氧化铁和氢氧化铁矿物层围绕着一个磷酸钙核心组成。为了研究各种矿物层与在其上生长的有机基质纤维之间的关系，使用聚焦离子束处理从牙齿的特定特征以受控取向制备了切片。通过一系列透射电子显微镜 (TEM) 技术，可以分析异质界面的组成和微观结构细节，以及有机基质纤维在矿物层内的命运。能谱 TEM 突出了各种矿物相的互锁性质，而高角环形暗场扫描 TEM 成像表明，有机基质在完全矿化的牙齿中仍然存在。这些对这种复杂生物材料结构的新见解是理解其结构和物理性质之间关系的重要一步，并且可能有助于解释其高强度和抗裂行为。
