Assembly of layers in 3D with guiding frames

• Applicant: Professor Dr. Andreas Heuer
• Subject Area: Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry
• Term: from 2016 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 332724984

In recent years, inspired by the properties of the cytoskeleton, the Liu group put forward the Frame Guided Assembly (FGA) strategy, by which amphiphilic molecules are guided by the frames to form size and shape defined assemblies. They have studied the FGA system with variable frames and amphiphilic molecules. For the frame the properties of DNA play a crucial role. These studies have improved the understanding on the molecular assembly mechanism. Furthermore, efficient methods have been established to prepare FGA systems. Several ideas exist to explore the use of FGA systems during this funding period. For example the frame is formed from DNA origami, which would allow for a large variability. By including different hydrophilic and hydrophobic molecules into the assembly, it is checked if this kind of vesicle can serve as a multiloading platform. Furthermore, the range of possible surface modifications is explored and enzyme digestion will be introduced and biocompatibility will be checked. Finally, the Liu group plans a systematic study of the underlying properties of FGA for the example of sodium dodecyl sulfate (SDS). By varying the density of frames and using different SDS concentrations, the possibility of FGA is systematically explored. In cooperation with the experimental group the Heuer group will analyse the FGA concept from a fundamental theoretical perspective. A key aspect of this project is to improve the understanding of the mechanisms and factors that influence the assembly in the FGA framework and give rise to more efficient self-assembly as compared to the standard formation of micelles and vesicles. In the course of the project the complexity of the amphiphilic molecules is increased. Starting from a minimum model system, optimized to form micelles, a detailed thermodynamic analysis, including free energy calculations, is planned. In this way the impact of FGA can be studied in great detail. In the next step, two microscopic systems will be studied which allows for an explicit comparison with the experiments. A detailed list of explicit exchange between the Liu and the Heuer group is provided, extending the successful cooperation between both groups from the previous years and allowing major synergy effects. The theoretical background, required for this specific project (e.g. self-assembly of model systems, mapping of coarse grained and microscopic systems, free energy calculations, DNA properties), is available in the Heuer group.

• DFG Programme: Research Grants
• International Connection: China
• Cooperation Partner: Professor Dr. Dongsheng Liu