Eilers, Y. et al. Proc. Natl Acad. Sci. USA 115, 6117–6122 (2018).

The recently described MINFLUX nanoscopy method allows for high-resolution monitoring of single molecules with a small fraction of the photons needed for conventional super-resolution microscopy. Although the method was shown to work well for high-resolution imaging of DNA origami structures and for single-particle tracking with high spatiotemporal resolution, its benefits for the investigation of single-particle movements were not fully explored. Eilers et al. now show that MINFLUX can be used to monitor molecular movements of a few nanometers at rates that far surpass the spatiotemporal resolution of conventional approaches. They demonstrated their approach by studying the thermal fluctuation of fluorophore-labeled DNA strands, and achieved ~2-nanometer localization precision with measurements as short as 400 microseconds. These results highlight the power of this approach for studying the dynamics of single molecules.