Development for single-molecule deep imaging method of biological sample under cryogenic conditions

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K22162
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 32:Physical chemistry, functional solid state chemistry, and related fields
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Fujiyoshi Satoru 東京工業大学, 理学院, 助教 (70371705)
• Project Period (FY): 2019-06-28 – 2021-03-31
• Keywords: １分子観察 / 可変浸レンズ / 蛍光顕微鏡 / 三次元イメージング / 生体試料

Outline of Final Research Achievements

Three-dimensional optical microscopy with a high numerical aperture (NA) remains challenging for thick biological specimens owing to aberrations arising from interface refractions. In this project, we have developed a variable immersion lens (VIL) for deep fluorescence imaging A VIL is a high-NA concentric meniscus lens and was used in combination with an aberration-corrected high-NA reflecting objective (TORA-FUJI mirror). VIL microscope enables diffraction-limited 1.2-NA imaging in water (refractive index of 1.34) at a depth of 0.3 mm by minimizing aberrations due to refraction of a sample interface. Another aberration due to refractive index mismatching between a mounting medium and an object can be also corrected by the VIL system because various fluids with different refractive indexes can be used as mounting media for the VIL. As a result, we have demonstrated that a cell spheroid can be imaged at a true dimension.

Free Research Field

物理化学

Academic Significance and Societal Importance of the Research Achievements

これまで細胞内の小器官を測定する場合、培養細胞ぐらいの厚さ（１０ミクロン）がせいぜいで組織レベルの試料になると細胞ごとの分解能が限界であった。我々の提案する方法は生体組織の中の小器官を鮮明に取得できる方法であり、とても大きな意義があると考えている。この技術は医学、薬学にもすぐに応用できる方法であり、こちらの方向を伸ばすことで社会に貢献したい。