Development of small thermodynamically stable NIR-II dyes, and their application as fluorescent probes.

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K15259
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 47010:Pharmaceutical chemistry and drug development sciences-related
• Research Institution: University of Toyama
• Principal Investigator: Tanioka Masaru 富山大学, 学術研究部薬学・和漢系, 助教 (40846359)
• Project Period (FY): 2022-04-01 – 2024-03-31
• Keywords: 近赤外光 / キサンテン色素 / 架橋キサンテン色素 / 低分子量 / 熱力学的安定性 / 架橋フルオレセイン / 架橋ロドール / 無極性選択発光

Outline of Final Research Achievements

We developed small and thermodynamically stable near-infrared dyes based on "bridged xanthene dyes". Through this study, we succeeded in obtaining two new results, as described below. [1] We have clarified the synthetic method and optical properties of fluorescein-type bridged xanthene dyes (BFLs), and have succeeded in developing small-molecule NIR-I and -II dyes with less than 350 g/mol. [2] We discovered that rhodol-type bridged xanthene dyes (BRO) exhibit a new phenomenon called "non-polar selective emission (NPSE)," in which they emit light only in non-polar environments, and also found their potential as emission sensors and security inks.

Free Research Field

有機化学

Academic Significance and Societal Importance of the Research Achievements

「大きく・不安定であった」近赤外色素を「小さく・安定」にするための方法論は、新たな近赤外テクノロジーの開拓を可能にする点で材料化学分野に対して学術的意義を有する。また、本研究で発見した「無極性選択発光」現象は、新たな光物理現象として、光化学や理論化学分野の発展に資する。さらに、本研究で創出した色素を用いた水中での近赤外光レドックス触媒反応は、『生体の光レドックス治療』の第一歩と考えられるため、新たな光治療の創出に貢献する点で社会的な意義を有する。