Synthesis of monodisperse rod-shaped silica particles through biotemplating of surface-functionalized bacteria

摘要

Mesoporous silica particles of controlled size and shape are potentially beneficial for many applications, but their usage may be limited by the complex procedure of fabrication. Biotemplating provides a facile approach to synthesize materials with desired shapes. Herein, a bioinspired design principle is adopted through displaying silaffin-derived 5R5 proteins on the surface of Escherichia coli by genetic manipulations. The genetically modified Escherichia coli provides a three-dimensional template to regulate the synthesis of rod-shaped silica. The silicification is initiated on the cell surface under the functionality of 5R5 proteins and subsequentially the inner space is gradually filled. Density functional theory simulation reveals the interfacial interactions between silica precursors and R5 peptides at the atomic scale. There is a large conformation change of this protein during biosilicification. Electrostatic interactions contribute to the high affinity between positively charged residues (Lys4, Arg16, Arg17) and negatively charged tetraethyl orthosilicate. The hydrogen bonds develop between Arg16 (O—H), Arg17 (O—H and N—H) and Leu19 (O—H) residues and the forming silica agglomerates. In addition, the resulting rod-shaped silica copy of the bacteria can transform into mesoporous SiOx nanorods composed of carbon-coated nanoparticles after carbonization, which is shown to allow superior lithium storage performance.

平航

研究员

武汉理工大学材料复合新技术全国重点实验室研究员、博士生导师，国家级高层次青年人才，主要研究方向是生物过程启示的限域制备新技术与陶瓷材料低温制备新技术。

邹朝勇

研究员

武汉理工大学材料复合新技术国家重点实验室研究员，国家级高层次人才（青年项目），湖北省高层次人才，主要研究方向是生物过程启示的制备技术

彼得·弗拉茨尔（Peter Fratzl）

德国马普胶体与界面研究所教授、德国国家科学院院士

德国马普胶体与界面研究所生物材料系主任，生物与仿生材料科学领域的国际著名学者，研究天然材料（骨骼、木材、贝壳等）的分层结构与物理性能关系。

王为民

首席教授、博士生导师

武汉理工大学首席教授，博士生导师。

傅正义

中国工程院院士

中国工程院院士，武汉理工大学教授。