有机小分子荧光基团由于其独特的发光机制和易于调控结构的特点，为医学成像领域注入了新的材料支持。 NIR-II窗口成像的巨大潜力迫使我们不断优化有机荧光物质的结构，设计出更好的荧光分子以用于荧光成像引导手术。理想的有机小分子荧光基团应能够穿透生物体内部，清晰地显示不同组织的内部结构和边缘轮廓，从而实现完美的内部成像并准确指导外部手术。在体内，荧光基团不会对正常组织和器官造成损害。然而，NIR-II荧光小分子存在量子产率低和生物相容性差等问题，严重限制了其在临床转化中的应用。为了尽可能避免NIR-II荧光探针的缺点，并更好地实现图像引导手术，本实验将双飞行子单位纳入扭曲的D-π-A-π-D结构中，以扩展荧光基团的共轭结构，既实现了NIR-II发射，又具有高量子产率和生物安全性。版权所有 © 2023 Elsevier B.V. 保留所有权利。

Organic small molecule fluorescent groups have injected new material support into the field of medical imaging due to their unique luminescence mechanism and easy tuning of structure. The great potential of NIR-II window imaging forces us to continuously optimize the structure of organic fluorophores to design better fluorescent molecules for fluorescence imaging-guided surgery. An ideal organic small molecule fluorescent group: it can penetrate into the inside of the organism, clearly present the internal structure and the edge contour of different tissues, so as to perfectly achieve internal imaging and accurately guide external surgery. In vivo, fluorescent groups do not damage normal tissues and organs. However, problems such as low quantum yield and poor biocompatibility greatly limit the clinical transformation of NIR-II fluorescent small molecules. To avoid the shortcomings of NIR-II fluorescent probes as much as possible and better realize image-guided surgery, in this experiment, the biplane donor unit was incorporated into the twisted D-π-A-π-D structure to expand the conjugated structure of the fluorescent group, which not only realized NIR-II emission, but also had high quantum yield and biosafety.Copyright © 2023 Elsevier B.V. All rights reserved.