Atomistic Modeling of Organic-Inorganic Interfaces in Biosilica

在该研究单位的第一个资助期内，解决了两个主要问题：(a)以简单模型系统为例，了解胆碱分子和二氧化硅表面的相互作用性质和结构特征，以及(b)多胺分子在不同条件下的聚集倾向。在方法上，这些研究有助于基准和澄清原子经典力场的准确性和局限性，它们将为解决第二个资助阶段的各种问题奠定基础，该阶段的重点将放在有机-无机系统的原子建模上。我们将研究以下问题：(i)澄清多胺在生物二氧化硅形成中的催化作用；（ii）进一步了解多胺的聚集行为（以及后期的矽胶），重点关注主要的微观相互作用（静电、疏水、氢键）；（三）研究多胺与二氧化硅纳米团簇和二氧化硅表面之间的空间组织和相互作用的性质；（iv）对多胺与其他有机成分（如甲壳素和矽胶）的相互作用进行初步研究。我们将同时使用量子力学和经典模拟技术，并旨在进一步加强与实验伙伴的合作。

During the first funding period of the research unit, two major questions were addressed: (a) understanding the interaction properties and structural features of choline molecules and silica surfaces as a case study on a simple model system, and (b) aggregation tendencies of polyamine molecules under various conditions. Methodologically, these investigations helped to benchmark and clarify both the accuracy and the limitations of atomistic classical force fields and they will build the basis to address various problems during the second funding phase, where the focus will be on the atomistic modelling of organic-inorganic systems. We will investigate the following issues: (i) Clarifying the hypothesized catalytic effect of polyamines in biosilica formation; (ii) Gaining additional insights into the aggregation behavior of polyamines (and silaffins in a later stage) with a focus on the dominant microscopic interactions (electrostatic, hydrophobic, hydrogen-bond); (iii) Addressing spatial organization and the nature of the interactions between polyamines and silica nanoclusters and silica surfaces; and (iv) Performing initial studies of the interaction of polyamines with other organic components such as chitin and silaffins. We will use both, quantum mechanical and classical simulation techniques and aim at further strengthen our cooperation with the experimental partners.