Creation of Novel Second Near-infrared Dyes based on pi-Conjugated Molecules Toward Imaging Applications

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K05439
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 33010:Structural organic chemistry and physical organic chemistry-related
• Research Institution: Kyushu University
• Principal Investigator: Ishida Masatoshi 九州大学, 工学研究院, 助教 (60706951)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: ポルフィリン / 近赤外光 / イメージング / 金属錯体

Outline of Final Research Achievements

Recently, optical imaging technology in the second near-infrared (NIR-II) window has attracted attention due to the advantage of high S/N ratio as well as real-time detection at deeper penetration in biological tissues compared to the light energy in the traditionally-used visible and first near-infrared window (NIR-I) regions.
In this project, we focussed on several porphyrins and their analogues as potential NIR-II chromophore scaffolds, offering new opportunities for optical materials to be used in the fields ranging from light-harvesting to sensing and therapeutic applications. A series of large pi-conjugated “N-confused” porphyrin analogues containing inverted pyrrole rings provided the desired optical properties in the use of optical applications.

Free Research Field

錯体化学

Academic Significance and Societal Importance of the Research Achievements

このような短波赤外光を積極的に活用した光学材料の開発は、カーボンナノチューブや希土類系無機ナノ粒子といったNIR-II発光材料が検討されているが、光励起効率、低スペクトル分離、潜在的な細胞毒性の問題が懸念されており、低分子有機系色素への代替開発が求められている。近年になってリアルタイム画像誘導手術などの応用展開が、ベンゾビスチアジアゾール系のD-A型色素を基盤とした研究が達成されつつあり、次世代臨床応用の展開において、環拡張ポルフィリンを基盤とした色素群の開発研究が、NIR-II光による医療診断のフロンティアとなりうると期待される。