My research interest is focused on the establishment and development of advanced light microscopy techniques and its application to the life sciences.
Fluorescence microscopes, and especially their confocal and two-photon variants, are unique in their ability to directly observe morphological changes and molecular reactions in living cells. However, due to diffraction of light, the lateral resolution of conventional light microscopes is limited to about 200-300 nm. This limitation is overcome with great success by the field of super-resolution microscopy. Here, fluorescence molecules do not only act as probes to highlight features of interest, but their photophysical properties are used for overcoming the diffraction limit of light. By controlling those properties in space or time with light it is possible to improve the spatial resolution of an optical microscope down to the molecular scale (10-20nm).
My overarching scientific objective is to develop novel paradigms and concepts based on super-resolution microscopy to address contemporary challenges in biophysics and molecular biology. To achieve these goals I will push forward the quantitative aspect of live cell imaging by setting-up and applying different concepts of super-resolution microscopy based on single molecule detection (PALM/STORM/GSDIM) and targeted switching (STED/RESOLFT). These next generation microscopes will allow the precise identification of populations of biomolecules depending on their localization, abundance and dynamics inside their native environment. A special effort will be dedicated to investigate neuronal proteins, especially in synapses, where trafficking organelles and protein complexes are packed so tight in space that resolving them requires high resolution in space and time.