Generation of composites from borides with tuneable electrical conductivities using peptides optimized by genetic engineering; characterization of the bio-solid interactions by modelling and AFM

在与ITB小组的合作下，将在噬菌体和硼化物颗粒的化学生物学复合体中创建无机材料与多肽的相互作用。结合特性将通过基因工程进行优化，该工程将使用一种基于生物扫描特定多肽的筛选系统，该系统对具有不同物理性质的不同硼化物具有偏好。我们使用了两个模型系统：1)首先是以湿法合成的纳米颗粒形式存在的金属、磁性硼化物；2)然后是高温、稳定和惰性的富硼陶瓷，通过分子模拟确定了决定这些多肽对某种材料的选择性的关键因素。在量子化学计算的帮助下，固体表面以及与这些表面接触的溶剂和肽的力场将被开发出来。原子力显微镜将在实验中进行量化。多肽修饰的硼化物将被分析其磁性和导电性，以及热稳定性。这就要求对现有的复合材料样品的物理性能测量方法进行修改和调整。随后，该系统将针对陶瓷硼化物进行修改，并将针对这些特定的多肽进行开发。具有不同优化的多肽的双功能噬菌体可用于将不同的金属和半导体硼化物或金属和陶瓷无机物结合成具有不可预见的性质的纳米和微结构复合材料。我们还设想了由不同的肽序列组成的小蛋白质，每个肽序列都针对特定的无机材料进行了优化。这样，可以实现功能材料的明确的空间取向。从多肽与硼化物材料成键作用的联合实验和理论研究中获得的基础知识，对于进一步开发基于非氧化物固体的智能材料是至关重要的。它可能会为热电设备、场效应晶体管或生物医学系统等大量应用铺平道路。该项目建立在分子生物学研究人员和固态化学家以及原子力显微镜理论工作组和专家之间的密切互动基础上。

In collaboration with the ITB group, an interaction of inorganic materials with peptides shall be created in a chemobiological composite of phages and boride particles. Binding properties are to be optimized by genetic engineering which will employ a screening system based on biopanning specific peptides with preferences for different borides with different physical properties. Two model systems are used: 1) for a start a metallic, magnetic boride in form of wet-chemically synthesized nanoparticles 2) later on a boron-rich ceramic which is very high-temperature stable and inert.The key factors determining the preference of these peptides for a certain material shall be determined by molecular simulation. With the help of quantum chemical calculations, force fields for solid surfaces and solvents and peptides in contact with these surfaces are to be developed. Quantification will be performed experimentally by atomic force microscopy. The peptide-modified borides will be analysed for their magnetism and electrical conductivity, as well as thermal stability. This requires the modification and adjustment of established methods of physical properties measurements to composite samples. Later, the system will be modified for ceramic borides and specific peptides shall be developed for these as well. Bifunctional phages with differently optimized peptides might be used to combine different metallic and semiconducting borides or both metallic and ceramic inorganics into nano- and micro-structured composites with unforeseeable properties. We also envision small proteins consisting of different peptide sequences each optimized for a specific inorganic material. This way a well-defined spatial orientation of functional materials may be achieved. Basic knowledge gained from a joint experimental and theoretical study of bonding interactions between peptides and boride materials is crucial for further development of smart materials based on non-oxide solids. It can potentially pave the way for a wealth of applications such as thermoelectric devices, field effect transistors or biomedical systems. The project builds on the strong interaction between researchers from molecular biology and solid state chemists, as well as theoretically working groups and experts on atomic force microscopy.