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bioRxiv · 10.64898/2026.09.13.751305

Fully Two-Photon-Driven RESOLFT Microscopy for Super-Resolution Imaging inside Tissue

Ozaki-Noma, R.·Ishii, H.·Wazawa, T.·Sakamoto, J.·Kozawa, Y.·Kato, Y.·Mukai, E.·Nemoto, T.·Nagai, T.
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Abstract

Two-photon excitation (2PE) microscopy reaches deep into tissue but remains diffraction-limited, and existing 2PE-STED and 2PE-RESOLFT schemes still rely on single-photon depletion or photoswitching. Here we present 2P-RESOLFT microscopy, in which excitation and reversible photoswitching are both two-photon-driven. Using the positive photoswitchable protein Padron2, we achieved 205-nm lateral resolution and resolved previously unreported membrane protrusions of {beta} cells inside pancreatic pseudoislets.

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Ozaki-Noma, R., Ishii, H., Wazawa, T., Sakamoto, J., Kozawa, Y., Kato, Y., Mukai, E., Nemoto, T., Nagai, T.. 2026-09-18. Fully Two-Photon-Driven RESOLFT Microscopy for Super-Resolution Imaging inside Tissue. https://doi.org/10.64898/2026.09.13.751305

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