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bioRxiv · 10.1101/2022.03.18.484906

MINSTED nanoscopy enters the Angstrom localization range

Weber, M.·von der Emde, H.·Leutenegger, M.·Gunkel, P.·Cordes, V. C.·Sambandan, S.·Khan, T. A.·Keller-Findeisen, J.·Hell, S. W.
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Abstract

We report all-optical, room-temperature localization of fluorophores with precision in the [A]ngstrom range. These precisions are attained in a STED microscope, by encircling the fluorophore with the low-intensity edge of the STED donut beam, while constantly increasing the absolute donut power. Individual fluorophores bound to a DNA strand are localized with{sigma} = 4.7 [A], corresponding to a fraction of the fluorophore size, with only 2,000 detected photons. MINSTED fluorescence nanoscopy with single-digit nanometer resolution is exemplified by imaging nuclear pore complexes and the distribution of nuclear lamin in mammalian cells labeled by transient DNA hybridization. Since our experiments yield a localization precision{sigma} = 2.3 [A], estimated for 10,000 detected photons, we anticipate that MINSTED will open up entirely new areas of application in the study of macromolecular complexes in cells.

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Weber, M., von der Emde, H., Leutenegger, M., Gunkel, P., Cordes, V. C., Sambandan, S., Khan, T. A., Keller-Findeisen, J., Hell, S. W.. 2022-03-19. MINSTED nanoscopy enters the Angstrom localization range. https://doi.org/10.1101/2022.03.18.484906

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