Li Jiayi, Xia Qiming, Wu Tianxiang, Zhang Yuhuang, Peng Shiyi, Li Yifei, Li Yixuan, Lin Hui, Zhang Mingxi, Qian Jun
State Key Laboratory of Extreme Photonics and Instrumentations, Centre for Optical and Electromagnetic Research, College of Optical Science and Engineering, International Research Center for Advanced Photonics, Zhejiang University, Hangzhou, China.
Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China.
Nat Commun. 2025 May 13;16(1):4436. doi: 10.1038/s41467-025-59630-4.
The second near-infrared (NIR-II) window is widely acknowledged for its excellent potential in in vivo fluorescence imaging. Currently, NIR-II fluorescence imaging predominantly operates within the 900-1880 nm spectral range, while the region beyond 1880 nm has been disregarded due to the large light absorption of water. Based on a refined understanding of the effect of light absorption on imaging, we propose an approach that utilizes the previously neglected region surrounding the water absorption peak at ~1930 nm for imaging. Both simulations and experiments confirm that the water absorption contributes positively to imaging, enabling high-contrast in vivo fluorescence imaging in the 1880-2080 nm window. To further assess the applicability of this approach in different biological media, we extend our focus to fluorescence imaging in adipose tissue. This leads to the expansion of the imaging window to 1700-2080 nm, owing to the unique light absorption characteristics of adipose tissue. Our results demonstrate that the 1700-2080 nm region provides optimal imaging quality in adipose tissue, attributing to its moderate absorption and low scattering. This work advances our understanding of the interplay between light absorption and photon scattering in bioimaging, providing an insight for selecting optimal imaging windows to achieve high-contrast fluorescence imaging.
第二近红外（NIR-II）窗口因其在体内荧光成像方面的卓越潜力而广受认可。目前，NIR-II荧光成像主要在900 - 1880 nm光谱范围内进行，而1880 nm以上的区域由于水的光吸收较大而被忽视。基于对光吸收对成像影响的深入理解，我们提出了一种利用先前被忽视的、围绕~1930 nm水吸收峰的区域进行成像的方法。模拟和实验均证实，水吸收对成像有积极贡献，能够在1880 - 2080 nm窗口实现高对比度的体内荧光成像。为了进一步评估该方法在不同生物介质中的适用性，我们将重点扩展到脂肪组织中的荧光成像。由于脂肪组织独特的光吸收特性，这使得成像窗口扩展到1700 - 2080 nm。我们的结果表明，1700 - 2080 nm区域在脂肪组织中提供了最佳的成像质量，这归因于其适度的吸收和低散射。这项工作推进了我们对生物成像中光吸收与光子散射之间相互作用的理解，为选择最佳成像窗口以实现高对比度荧光成像提供了见解。
