---
title: "Two-Photon–Driven RESOLFT Microscopy Enables Super-Resolution Imaging Deep in Tissue"
id: "biorxiv-13-fully-two-photon-driven-resolft-microscopy-for-super-resolution-imaging-inside"
canonical_url: "https://medichelpline.com/clinical-feed/biorxiv-13-fully-two-photon-driven-resolft-microscopy-for-super-resolution-imaging-inside"
content_type: "clinical_feed_article"
specialty: "Radiology"
source_name: "bioRxiv (Biomedical Preprints)"
source_url: "https://www.biorxiv.org/content/10.64898/2026.09.13.751305v1?rss=1"
published_at: "2026-09-18T12:00:00.000Z"
evidence_level: "Verified Feed"
license: "CC-BY-NC-4.0 / Informational Use"
---
# Two-Photon–Driven RESOLFT Microscopy Enables Super-Resolution Imaging Deep in Tissue
## Provenance & Clinical Metadata
- **Canonical URL:** https://medichelpline.com/clinical-feed/biorxiv-13-fully-two-photon-driven-resolft-microscopy-for-super-resolution-imaging-inside
- **Specialty:** [Radiology](https://medichelpline.com/clinical-feed/radiology.md)
- **Primary Source:** bioRxiv (Biomedical Preprints)
- **Source URL:** [Original Journal Publication](https://www.biorxiv.org/content/10.64898/2026.09.13.751305v1?rss=1)
- **Published At:** 2026-09-18T12:00:00.000Z
- **Evidence Rating:** Verified Feed
## Executive GIST (TL;DR)
- The study reports a fully **two-photon-driven RESOLFT** microscopy approach in which both excitation and reversible photoswitching are driven by two-photon absorption rather than relying on single-photon processes. - Researchers used the positive photoswitchable protein **Padron2** as the photoswitchable label for this method. - The method produced a measured lateral resolution of **205 nm**, demonstrating super-resolution capability beyond the diffraction limit with two-photon excitation. - Using this approach the authors resolved previously unreported membrane protrusions of **β cells** within **pancreatic pseudoislets**, indicating applicability for imaging cellular structures inside tissue-like samples. - The work contrasts with existing **2PE‑STED** and 2PE‑RESOLFT implementations that still depend on single-photon depletion or photoswitching for the non-linear step. - The manuscript is a preprint (bioRxiv) and has not been peer reviewed; funding sources reported include several Japanese agencies and programs. - Authors and correspondence details are provided; the DOI and posting date are listed in the source. - No competing interests were declared by the authors in the source document.
## Clinical Analysis & Structured Key Points
Fully Two-Photon-Driven RESOLFT Microscopy for Super-Resolution Imaging inside Tissue | bioRxiv Skip to main content New Results Fully Two-Photon-Driven RESOLFT Microscopy for Super-Resolution Imaging inside Tissue Ryohei Ozaki-Noma , Hirokazu Ishii , Tetsuichi Wazawa , View ORCID Profile Joe Sakamoto , Yuichi Kozawa , Yuta Kato , Eri Mukai , Tomomi Nemoto , Takeharu Nagai doi: https://doi.org/10.64898/2026.09.13.751305 Ryohei Ozaki-Noma 1 SANKEN, The University of Osaka; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Hirokazu Ishii 2 Division of Biophotonics, National Institute for Physiological Sciences (NIPS), National Institutes of Natural Sciences (NINS); Find this author on Google Scholar Find this author on PubMed Search for this author on this site Tetsuichi Wazawa 1 SANKEN, The University of Osaka; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Joe Sakamoto 3 Hamamatsu University School of Medicine; Find this author on Google Scholar Find this author on PubMed Search for this author on this site ORCID record for Joe Sakamoto Yuichi Kozawa 4 Institute of Multidisciplinary Research for Advanced Materials, Tohoku University; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Yuta Kato 5 Department of Biomedical Sciences, College of Life Sciences, Ritsumeikan University Find this author on Google Scholar Find this author on PubMed Search for this author on this site Eri Mukai 5 Department of Biomedical Sciences, College of Life Sciences, Ritsumeikan University Find this author on Google Scholar Find this author on PubMed Search for this author on this site Tomomi Nemoto 2 Division of Biophotonics, National Institute for Physiological Sciences (NIPS), National Institutes of Natural Sciences (NINS); Find this author on Google Scholar Find this author on PubMed Search for this author on this site Takeharu Nagai 1 SANKEN, The University of Osaka; Find this author on Google Scholar Find this author on PubMed Search for this author on this site For correspondence: ng1{at}sanken.osaka-u.ac.jp Abstract Info/History Metrics Supplementary material Preview PDF 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 β cells inside pancreatic pseudoislets. Competing Interest Statement The authors have declared no competing interest. Funder Information Declared Japan Science and Technology Agency Japan Society for the Promotion of Science Japan Agency for Medical Research and Development, https://ror.org/004rtk039 the Cooperative Study Program of National Institute for Physiological Sciences Joint Research of Exploratory Research Center on Life and Living Systems (ExCELLS) ExCELLS Encouragement Research for Young Scientists Toyoaki Scholarship Foundation Copyright The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY 4.0 International license . Back to top Previous Next Posted September 18, 2026. Download PDF Supplementary Material Email Thank you for your interest in spreading the word about bioRxiv. NOTE: Your email address is requested solely to identify you as the sender of this article. Your Email * Your Name * Send To * Enter multiple addresses on separate lines or separate them with commas. You are going to email the following Fully Two-Photon-Driven RESOLFT Microscopy for Super-Resolution Imaging inside Tissue Message Subject (Your Name) has forwarded a page to you from bioRxiv Message Body (Your Name) thought you would like to see this page from the bioRxiv website. Your Personal Message CAPTCHA This question is for testing whether or not you are a human visitor and to prevent automated spam submissions. Share Fully Two-Photon-Driven RESOLFT Microscopy for Super-Resolution Imaging inside Tissue Ryohei Ozaki-Noma , Hirokazu Ishii , Tetsuichi Wazawa , Joe Sakamoto , Yuichi Kozawa , Yuta Kato , Eri Mukai , Tomomi Nemoto , Takeharu Nagai bioRxiv 2026.09.13.751305; doi: https://doi.org/10.64898/2026.09.13.751305 Share This Article: Copy Citation Tools Fully Two-Photon-Driven RESOLFT Microscopy for Super-Resolution Imaging inside Tissue Ryohei Ozaki-Noma , Hirokazu Ishii , Tetsuichi Wazawa , Joe Sakamoto , Yuichi Kozawa , Yuta Kato , Eri Mukai , Tomomi Nemoto , Takeharu Nagai bioRxiv 2026.09.13.751305; doi: https://doi.org/10.64898/2026.09.13.751305 Citation Manager Formats BibTeX Bookends EasyBib EndNote (tagged) EndNote 8 (xml) Medlars Mendeley Papers RefWorks Tagged Ref Manager RIS Zotero Tweet Widget Facebook Like Google Plus One Subject Areas All Articles Animal Behavior and Cognition (8011) Biochemistry (18736) Bioengineering (14887) Bioinformatics (44408) Biophysics (22591) Cancer Biology (19720) Cell Biology (26897) Clinical Trials (138) Developmental Biology (13964) Ecology (21005) Epidemiology (2067) Evolutionary Biology (25441) Genetics (16162) Genomics (23499) Immunology (18698) Microbiology (42465) Molecular Biology (18057) Neuroscience (93424) Paleontology (700) Pathology (2977) Pharmacology and Toxicology (5094) Physiology (8113) Plant Biology (15999) Scientific Communication and Education (2095) Synthetic Biology (4559) Systems Biology (10235) Zoology (2390)
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