Chiton tooth composites: from biosynthetic mechanisms to bioinspired, highly wear resistant materials

大自然对牙齿和骨骼等矿化组织的结构和特性有着不可思议的控制，可以以任何方式弯曲单晶，并创造出坚韧、重量轻、自我修复的骨骼结构。矿物周围的有机基质在选择性地形成和模板化亚稳矿物前体并指导其转化为最终状态方面起着关键作用。大自然的精确控制从原子水平开始，超过了目前的合成能力。现代材料制造缺乏落后，需要大量的能量来加工和合成半导体、医药或建筑材料——通常是在高温高压下广泛的自上而下的制造步骤。科学家有责任找到减少碳足迹的创新方法。该项目的总体目标是更好地了解石鳖牙齿的生物矿化，石鳖牙齿是由最坚硬和最耐磨的生物材料之一，磁铁矿/几丁质复合材料组成，并将这些新知识转化为具有优异性能的新型纳米复合材料的合成。为此，1)我用最先进的蛋白质组学方法研究了有机基质中蛋白质在牙齿形成过程中的作用。2)运用Mössbauer成像新技术，近距离观察牙齿发育不同阶段的铁种类。3)我使用自组装单层（sam）来模拟基于第1点和第2点发现的生物启发铁结合基序的有机/无机相互作用。4)我将这些知识转移到研究功能化甲壳素/磁铁矿纳米复合材料的形成。这个项目将激发我的灵感，并提供独特的培训，让我接触到化学、生物学和材料科学相结合的多学科领域，使我能够开始自己的学术生涯。

Nature possesses an unreached control over structure and properties of mineralized tissues such as teeth and bones, curving single crystals in any fashion and creating tough and light weight self-repairing skeletal structures. An organic matrix surrounding the minerals plays a critical role in selectively forming and templating metastable mineral precursors and directing its transformation into the final state. Nature’s precise control starts from atomic level and exceeds current synthetic capabilities. Modern material fabrication lacks behind and needs large amount of energy to process and synthesize materials for semiconductors, medicine or construction – often in extensive top-down fabrication steps at high temperature and high pressure. It is a responsibility of scientists to find innovative methods for decreasing the carbon footprint of this. The overall aim of the project is to better understand the biomineralization of the chiton’s teeth, which consists of one of the hardest and most wear-resistant biogenic materials, a magnetite/chitin composite, and to transfer this new knowledge into the synthesis of new nanocomposite materials with outstanding properties. For this,1) I investigate the role of the proteins in the organic matrix during tooth formation by state-of-the-art proteomics methods. 2) I apply the novel technique of Mössbauer imaging to have a closer look on the iron species in the different stages of development of the teeth. 3) I use selfassembled monolayers (SAMs) to mimic the organic/inorganic interactions based upon bioinspired iron binding motif discovered by point 1 and 2. 4) I transfer this knowledge to investigate the formation of a functionalized chitin/magnetite nanocomposite. This project will inspire and offer unique training by exposing me to this multidisciplinary field where chemistry, biology and materials science meet, enabling me to embark on my own academic career.