14:45 〜 15:10
[BPT03-05] バイオミネラルのナノテクトニクス
★招待講演
キーワード：バイオミネラル、シリカ、炭酸カルシウム、メソクリスタル
Conventional technology of material fabrication has been mainly focused on the production of large-sized homogeneous bodies, such as single crystals and bulky glass, for achievement of their specific properties without degradation due to disordering and grain boundaries. On the other hand, biomimerals have completely different architectures from the artificial materials. The complicated hard frameworks of various biominerals are commonly composed of nanoscale building blocks regardless of crystalline and non-crystalline substances. The fascinating biological structural design, “nanotectonics”, has attracted the interest of many researchers in a broad range of science and technology fields. Nanotectonics is based on the designed organization of nanoscale building blocks into organized structures. Multilevel hierarchy from nanometer to millimeter lengths is observed in sophisticated architectures of various biominerals. Here, we learn nanotectonics of the biological superstructures associated with specific organic molecules from silicas in rice plants and marine planktons, calcium carbonates in seashells, coral skeletons, and foraminiferal shells, calcium phosphates of vertebrate teeth, calcium oxalates in plants, barium sulfates of radiolarian skeletons, and guanine in sapphirina. Especially, the biologically produced crystalline phases are categorized to mesocrystals, which are comprised of crystallographically oriented nanoscale blocks. The particular interaction of inorganic and organic substances in the superstructures of biominerals is discussed from in vitro production of their mimetics in artificial systems. The formation of mesocrystals is associated with nonclassical crystallization processes including biological and biomimetic routes in the presence of organic and other kinds of additives. The life ability inspires us bottom-up soft chemical approach for fabrication of superstructures consisting of nanoscale building blocks as a novel type of functional materials.