Researchers analyse molecular self-organisation with atomic resolution

Researchers analyse molecular self-organisation with atomic resolution

Scientists around the world are working to make matter "intelligent" - natural membranes or proteins, whose function results from complex structures, can serve as models. To change material properties, the ability of molecules to arrange themselves independently is often used. A group led by the three professors Christos Gatsogiannis and Bart Jan Ravoo from the University of Münster and Kenichiro Itami from the RIKEN research institute in Japan has now shown that peptides, i.e. short chains of amino acids, spontaneously fold, stack, and form fibres with long channels in water. Even low concentrations of the peptides (less than one gram in 100 ml of water) form a stable gel with a high water content, known as a hydrogel. The team determined the structure and interactions of the molecules using cryo-electron microscopy at the atomic level, with a resolution of 1.7 Ångström. An Ångström is a ten-millionth of a millimetre, corresponding to the order of magnitude of atomic radii.

'This microscopic resolution is a world record for the analysis of self-organising synthetic materials,' emphasises Christos Gatsogiannis from the Institute of Medical Physics and Biophysics. 'It allows detailed conclusions about how self-organisation works.' The scientists used amino acids with a flat network of aromatic hydrocarbons. These are elementary building blocks for organic electronic and optical materials. Their structure causes the peptides to interact strongly and precisely with each other in water. Based on their observations, the team developed a model for the stepwise self-organisation that could also be applied to other molecules. The hydrogels produced here could be used as storage for active ingredients or as a scaffold for tissue. In the future, other supramolecular materials with special optical or self-healing properties could be produced from biologically-synthetic hybrid building blocks similar to those of the current study.

In nature, complex materials also arise through the self-organisation of many small and large molecules. Their precise but dynamic arrangement in space and time determines the functionality of the material. The principle of self-organisation in nature is increasingly being used to produce synthetic functional materials. Often, biological and artificial components are used together, thus combining properties from both areas.

The method: for the study, the researchers synthesised amino acids with extended aromatic units and linked them to form peptides. They then added the peptides to water, mixed thoroughly, and allowed the mixture to rest for several hours. During this time, the pH value was gradually lowered, causing the gel to form. The team examined its deformation and flow behaviour and analysed it in detail using cryo-electron microscopy at the Center for Soft Nanoscience of the University of Münster. In this process, the samples are rapidly frozen and examined at extremely low temperatures (minus 180 degrees Celsius).

The project was carried out within the International Research Training Group Münster-Nagoya. It was funded by the German Research Foundation (DFG; IRTG 2678) and the "Japan Society for the Promotion of Science".

Original publication

A. Ueda, G. Broutzakis, A. Neuhaus, D. Ens, D. Mählmann, L. Schlichter, H. Kono, A. Yagi, K. Amaike, C. Gatsogiannis, B. J. Ravoo, K. Itami: Atomic-precision π-driven peptide hydrogel nanofibers with ordered water channels. Nat Commun 17, 7622 (2026). https://doi.org/10.1038/s41467-026-75984-9.

Further information

• Original publication
• Prof Dr Christos Gatsogiannis at the University of Münster
• Prof Dr Bart Jan Ravoo at the University of Münster