Entwicklung eines ultraschnellen elektro-optischen Scanners für STED-Nanoskopie

Fluorescence microscopy is a widely used technique in biology and other life sciences. It enables non-invasive imaging of specifically labeled tissue, cellular structures or molecules. Information about the structure as well as molecular interactions within intact biological samples can be gained. Since the invention of fluorescence microscopy, numerous techniques have attained to maximize the signal to noise ratio as well as the spatial and temporal resolution. In this work, an ultrafast electro-optical laser scanning system is developed aiming to improve these performance parameters. The scanning system is integrated into STED microscopes which allow diffraction unlimited high spatial resolution through stimulated emission of the fluorophores. With the scanner, the pixel dwell time is reduced down to the fundamental limit of fluorescence lifetime. The developed setup is currently the fastest STED microscope. Compared to conventional systems, the frame rate is increased three to five orders of magnitude. It enables to observe dynamic processes with a temporal resolution of 1000 fps, high spatial resolution down to < 50 nm and a up to 4.5 times increased fluorescence signal in one setup. Thus, new and challenging biological questions for example in the field of DNA dynamics or synaptic interactions can be addressed in more detail