Dickerson M B, Naik R R, Sarosi P M, Agarwal G, Stone M O, Sandhage K H
School of Materials Science and Engineering, Georgia Institute of Technology, 771 Ferst Drive, Atlanta, Georgia 30332-0245, USA.
J Nanosci Nanotechnol. 2005 Jan;5(1):63-7. doi: 10.1166/jnn.2005.008.
A novel biosynthetic paradigm is introduced for fabricating three-dimensional (3-D) ceramic nanoparticle assemblies with tailored shapes and tailored chemistries: biosculpting and shape-preserving inorganic conversion (BaSIC). Biosculpting refers to the use of biomolecules that direct the precipitation of ceramic nanoparticles to form a continuous 3-D structure with a tailored shape. We used a peptide derived from a diatom (a type of unicellular algae) to biosculpt silica nanoparticle based assemblies that, in turn, were converted into a new (nonsilica) composition via a shape-preserving gas/silica displacement reaction. Interwoven, microfilamentary silica structures were prepared by exposing a peptide, derived from the silaffin-1A protein of the diatom Cylindrotheca fusiformis, to a tetramethylorthosilicate solution under a linear shear flow condition. Subsequent exposure of the silica microfilaments to magnesium gas at 900 degrees C resulted in conversion into nanocrystalline magnesium oxide microfilaments with a retention of fine (submicrometer) features. Fluid(gas or liquid)/silica displacement reactions leading to a variety of other oxides have also been identified. This hybrid (biogenic/synthetic) approach opens the door to biosculpted ceramic microcomponents with multifarious tailored shapes and compositions for a wide range of environmental, aerospace, biomedical, chemical, telecommunications, automotive, manufacturing, and defense applications.
一种用于制造具有定制形状和定制化学组成的三维（3-D）陶瓷纳米颗粒组件的新型生物合成范例被引入：生物雕刻与形状保持无机转化（BaSIC）。生物雕刻是指利用生物分子引导陶瓷纳米颗粒沉淀，以形成具有定制形状的连续3-D结构。我们使用了一种源自硅藻（一种单细胞藻类）的肽来生物雕刻基于二氧化硅纳米颗粒的组件，这些组件进而通过形状保持气体/二氧化硅置换反应转化为新的（非二氧化硅）组成。通过在直线剪切流条件下将源自硅藻梭形筒柱藻的硅亲和蛋白-1A的肽暴露于原硅酸四甲酯溶液中，制备了交织的微丝状二氧化硅结构。随后在900摄氏度下将二氧化硅微丝暴露于镁气中，导致其转化为保留精细（亚微米级）特征的纳米晶氧化镁微丝。还确定了导致多种其他氧化物的流体（气体或液体）/二氧化硅置换反应。这种混合（生物源/合成）方法为具有多种定制形状和组成的生物雕刻陶瓷微部件打开了大门，可用于广泛环境、航空航天、生物医学、化学、电信、汽车、制造和国防应用。
