In vivo oxygen mapping based on lifetime imaging microscopy using phosphorescent molecule

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K22947
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 90:Biomedical engineering and related fields
• Research Institution: Gunma University
• Principal Investigator: Yoshihara Toshitada 群馬大学, 大学院理工学府, 准教授 (10375561)
• Project Period (FY): 2019-06-28 – 2021-03-31
• Keywords: りん光 / りん光寿命 / 酸素 / イリジウム錯体 / 細胞 / 組織

Outline of Final Research Achievements

In this study, we designed and synthesized intracellular oxygen probes based on red phosphorescent iridium complexes for sensing of oxygen levels in living cells and tissues, and a confocal phosphorescence lifetime imaging microscope (PLIM) for the measurements of oxygen partial pressure of mice was developed. Using these oxygen probes and PLIM, the detection and visualization of oxygen levels of hepatic lobules were succeeded. The PLIM images clearly visualized the oxygen gradient in hepatic lobules with cellular level resolution. Furthermore, we succeeded in real-time tracking of oxygen-dependent metabolic processes based on phosphorescence lifetime imaging of the liver in the same field of view.

Free Research Field

光化学

Academic Significance and Societal Importance of the Research Achievements

酸素は、我々が生命活動を維持するために必要不可欠な分子です。本研究では、麻酔下にあるマウスの臓器内の酸素分圧を計測・イメージングする方法論の開発に取り組みました。得られた研究成果から、世界で初めて、光学的方法を用いて肝臓内の酸素分圧分布をイメージングすることに成功しました。この知見は，がん腫瘍など，細胞が異常増殖し血流が不十分な組織内の酸素分圧を明らかにすることに繋がり，がんの発見，診断，治療法の開発に貢献することができます。