Nanoscale imaging of expanded cells and proteins with spontaneously blinking dyes

Sauer, M.; Taban, D.; Jungblut, M.; Budiarta, M.; Helmerich, D. A.; Kiesel, C.; Doose, S.; Kollmannsberger, P.; Plutkiss, S.; Lavis, L.; Rizzoli, S.; Shaib, A. H.; Krah, D.; Beliu, G.

doi:10.64898/2026.02.23.707413

bioRxiv · 10.64898/2026.02.23.707413

Nanoscale imaging of expanded cells and proteins with spontaneously blinking dyes

Sauer, M.·Taban, D.·Jungblut, M.·Budiarta, M.·Helmerich, D. A.·Kiesel, C.·Doose, S.·Kollmannsberger, P.·Plutkiss, S.·Lavis, L.·Rizzoli, S.·Shaib, A. H.·Krah, D.·Beliu, G.

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Abstract

Expansion microscopy (ExM) enables nanoscale imaging on standard microscopes, but combining ExM with single-molecule localization microscopy (SMLM) remains difficult, owing to the incompatibility of expanded hydrogels with photoswitching buffers. Here, we introduce a single-step expansion microscopy method that allows SMLM with spontaneously blinking dyes in 6-14x expanded samples, without re-embedding. We demonstrate nanometer-resolution imaging by resolving the organization of the nuclear pore complex (NPC) and the molecular structure of recombinant homotrimeric proliferating cell nuclear antigen (PCNA).

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Sauer, M., Taban, D., Jungblut, M., Budiarta, M., Helmerich, D. A., Kiesel, C., Doose, S., Kollmannsberger, P., Plutkiss, S., Lavis, L., Rizzoli, S., Shaib, A. H., Krah, D., Beliu, G.. 2026-02-23. Nanoscale imaging of expanded cells and proteins with spontaneously blinking dyes. https://doi.org/10.64898/2026.02.23.707413

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