Ytterbium-Based Bioprobes for Near-Infrared Two-Photon Scanning Laser Microscopy Imaging
Ytterbium-Based Bioprobes for Near-Infrared Two-Photon Scanning Laser Microscopy Imaging
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DOI：
10.1002/anie.201202212
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发表时间：
2012-01-01
影响因子：
16.6
通讯作者：
Maury, Olivier
中科院分区：
文献类型：
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作者：
D'Aleo, Anthony;Bourdolle, Adrien;Maury, Olivier
几十年来，光学显微镜一直是生物成像的重要工具，最近基于发光的技术已广泛应用于医学分析和诊断。 [1]使用商业生物探针或荧光蛋白的传统单光子显微镜通常使用紫外或可见光中的激发波长并在可见光谱范围内进行检测。根据激发到检测的光谱范围，这些显微镜配置将被称为紫外到可见光或可见到可见光。由于生物组织强烈吸收和散射紫外可见光，因此这种配置仅限于表面生物成像实验，例如二维细胞成像。另一方面，生物组织在 700 至 1200 nm 之间的近红外 (NIR) 区域（称为生物窗口的区域）的透明度允许在此光谱范围内进行深度成像。 [2]因此，目前许多学术和工业研究工作都集中在显微镜技术的改进和新型发光生物探针的设计上，该探针在近红外光谱范围内具有激发和发射特性。这种 NIR-to-NIR 配置中的显微镜将能够在厚组织中进行深度成像，并且在过去十年中已经开发出结合 NIR 激发和发射的几种生物探针（花青、(aza)-bodipy）并已商业化。 [3]然而，在这些情况下，激发和发射光的最佳收集范围之间的小斯托克斯位移对于显微镜来说是一个真正的技术缺陷，因为需要将发射与激发完全分离。非线性双光子激发，即通常在近红外区域同时吸收两个半能光子，本质上会引入更大的斯托克斯位移，因此是规避这一缺点的一种优雅方法。 [4]然而，到目前为止，所有设计的发色团都在可见光谱范围内表现出发射，并且当前可用的双光子显微镜在这种两光子近红外到可见光配置中工作，检测波长比入射激光短。 [4, 5]
For decades, optical microscopy has been an essential tool for biological imaging, and more recently luminescence-based techniques have gained widespread utilization for medical analyses and diagnostics.[1] Conventional one-photon microscopy using commercial bio-probes or fluorescent proteins generally proceeds using excitation wavelength in the UV or visible and detection in the visible spectral range. These microscopy configurations will be referred to as UV-to-visible or visible-to-visible according to the excitation-to-detection spectral ranges. Since biological tissues strongly absorb and scatter UV-visible light, such configurations are restricted to surface bio-imaging experiments eg 2D cell imaging. On the other hand, the transparency of biological tissues in the near infra-red (NIR) between 700 and 1200 nm, a region called biological window, allows in-depth imaging in this spectral range.[2] Therefore, numerous academic and industrial research endeavors are currently focused on the improvement of microscopy techniques and on the design of new luminescent bio-probes featuring both excitation and emission in this NIR spectral range. Microscopy in this NIR-to-NIR configuration will enable in depth imaging in thick tissues and several bio-probes (cyanine,(aza)-bodipy) combining NIR excitation and emission have been developed and commercialized this last decade.[3] However in these cases, the small Stokes shift between the excitation and the optimal collection range of emitted light is a real technical drawback for microscopy because of the need to cleanly separate the emission from the excitation. Nonlinear biphotonic excitation, that is the simultaneous absorption of two photons of half energy typically in the NIR region, inherently introduces a larger Stokes shift and is therefore an elegant way to circumvent this drawback.[4] However, up to now, all the designed chromophores exhibit an emission in the visible spectral range, and the currently available biphotonic microscopes work in this two photon NIR-to-visible configuration with detection wavelength shorter than the incident laser one.[4, 5]