Institute of Optical Materials and Chemical Biology, Guangxi Key Laboratory of Electrochemical Energy Materials, School of Chemistry and Chemical Engineering, Guangxi University, Nanning, Guangxi 530004, P. R. China.
Department of Chemistry and Nanoscience, Ewha Womans University, Seoul, 03760, Korea.
Angew Chem Int Ed Engl. 2024 Jan 8;63(2):e202312632. doi: 10.1002/anie.202312632. Epub 2023 Oct 27.
Photoacoustic (PA) imaging is emerging as one of the important non-invasive imaging techniques in biomedical research. Small molecule- second near-infrared window (NIR-II) PA dyes combined with imaging data can provide comprehensive and in-depth in vivo physiological and pathological information. However, the NIR-II PA dyes usually exhibit "always-on" properties due to the lack of a readily optically tunable group, which hinders the further applications in vivo. Herein, a novel class of dyes GX have been designed and synthesized as an activatable NIR-II PA platform, in which the absorption/emission wavelength of GX-5 extends up to 1082/1360 nm. Importantly, the GX dyes have a strong tissue penetration depth and high-resolution for the mouse vasculature structures in NIR-II PA 3D imaging and high signal-to-noise ratio in NIR-II fluorescence (FL) imaging. Furthermore, to demonstrate the applicability of GX dyes, the first NIR-II PA probe GX-5-CO activated by carbon monoxide (CO) was engineered and employed to reveal the enhancement of the CO levels in the hypertensive mice by high-contrast NIR-II PA and FL imaging. We expect that many derivatives of GX dyes will be developed to afford versatile NIR-II PA platforms for designing a wide variety activatable NIR-II PA probes as biomedical tools.
光声（PA）成像是生物医学研究中一种重要的非侵入性成像技术。小分子近红外二区（NIR-II）PA 染料与成像数据相结合，可以提供全面、深入的体内生理和病理信息。然而，由于缺乏易于光调控的基团，NIR-II PA 染料通常表现出“常开”特性，这阻碍了其在体内的进一步应用。在此，我们设计并合成了一类新型染料 GX，作为一种可激活的 NIR-II PA 平台，其中 GX-5 的吸收/发射波长延伸至 1082/1360nm。重要的是，GX 染料在 NIR-II PA 3D 成像中具有很强的组织穿透深度和对小鼠脉管结构的高分辨率，以及在 NIR-II 荧光（FL）成像中的高信噪比。此外，为了证明 GX 染料的适用性，我们设计并合成了第一个由一氧化碳（CO）激活的 NIR-II PA 探针 GX-5-CO，用于通过高对比度 NIR-II PA 和 FL 成像来揭示高血压小鼠中 CO 水平的增强。我们期望开发出许多 GX 染料的衍生物，为设计各种可激活的 NIR-II PA 探针提供多功能的 NIR-II PA 平台，作为生物医学工具。
