STimulated Emission Depletion (STED) – Microscope

• Subject Area: Chemical Solid State and Surface Research
• Term: Funded in 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 547559178

A STED microscope (Stimulated Emission Depletion) is being applied for, which will be used for high-resolution optical examination of dye-labeled samples with a sub-50 nm resolution. The areas of application range across the disciplines from physicochemical and materials chemistry motivated work, primarily on polymeric and organic systems, to microbiology and cell biology. Since STED microscopy can be used to examine a broad range of differrent sample classes that can be labeled with fluorescent dyes or that fluoresce inherently, the method is ideal for use as an integral part of a future research center INCYTE (Interdisciplinary Research Center for Nanoanalytics, Nanochemistry and Cyberphysical Sensor Technologies), the interdisciplinary core facility at the University of Siegen. The STED microscope will enable high-resolution fluorescence measurements on very different systems and under different conditions. In nanochemistry, this concerns, on the one hand, the localization of dye markers on nanoscale polymer samples and polymer architectures, the investigation of novel fluorescence-based probe molecules and sensory approaches as well as time-resolved analysis of dynamic processes under well-defined conditions with regard to temperature and the composition of solid-liquid media or liquid-liquid interfaces. Furthermore, the interaction of cells with nanostructured polymers, the mode of action of stimulus-responsive polymer layers for cell separation, the diffusion of active ingredients into and release from polymeric matrices, questions of molecular and cellular physiology, biomaterials made of chitin and chitosan, and the function of chitin acetylation codes in insects, RNA in neurodegenerative diseases and microbial cocultures (also in S1 / S2 laboratories) can be examined with high resolution. Above all, the high spatial resolution should provide much deeper insights than is currently possible through ensemble-averaging techniques or fluorescence microscopy with diffraction-limited resolution, both in established and new nanoscale and nano- or microstructured systems in terms of functional structure-property relationships. The microscopy experiments in one of the core projects aim to elucidate the growth, shrinkage and coalescence processes of surface nanobubbles in aqueous media on differently functionalized and structured surfaces. In particular, high-resolution non-invasive tracking of the bubbles will be used to analyze, which changes occur when state variables such as temperature, pressure, or the concentration of co-solutes change, which will be used for a better understanding of surface nanobubbles and the falsification of new theoretical approaches.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: STED-Mikroskop für die hochaufgelöste Fluoreszenzmikroskopie
• Instrumentation Group: 5090 Spezialmikroskope
• Applicant Institution: Universität Siegen
• Leader: Professor Dr. Holger Schönherr