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bioRxiv · 10.1101/2023.05.11.540319

High-speed TIRF and 2D super-resolution structured illumination microscopy with large field of view based on fiber optic components

Ortkrass, H.·Schuerstedt, J.·Wiebusch, G.·Szafranska, K.·McCourt, P.·Huser, T.
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Abstract

Super-resolved structured illumination microscopy (SR-SIM) is among the most flexible, fast, and least perturbing fluorescence microscopy techniques capable of surpassing the optical diffraction limit. Current custom-built instruments are easily able to deliver two-fold resolution enhancement at video-rate frame rates, but the cost of the instruments is still relatively high, and the physical size of the instruments based on the implementation of their optics is still rather large. Here, we present our latest results towards realizing a new generation of compact, cost-efficient, and high-speed SR-SIM instruments. Tight integration of the fiber-based structured illumination microscope capable of multi-color 2D- and TIRF-SIM imaging, allows us to demonstrate SR-SIM with a field of view of up to 150 x 150 m2 and imaging rates of up to 44 Hz while maintaining highest spatiotemporal resolution of less than 100 nm. We discuss the overall integration of optics, electronics, and software that allowed us to achieve this, and then present the fiberSIM imaging capabilities by visualizing the intracellular structure of rat liver sinusoidal endothelial cells, in particular by resolving the structure of their trans-cellular nanopores called fenestrations.

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Ortkrass, H., Schuerstedt, J., Wiebusch, G., Szafranska, K., McCourt, P., Huser, T.. 2023-05-12. High-speed TIRF and 2D super-resolution structured illumination microscopy with large field of view based on fiber optic components. https://doi.org/10.1101/2023.05.11.540319

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