Optical imaging plays a central role in biology and medicine but is hindered by light scattering in live tissue. We report the counterintuitive observation that strongly absorbing molecules can achieve optical transparency in live animals. We explored the physics behind this observation and found that when strongly absorbing molecules dissolve in water, they can modify the refractive index of the aqueous medium through the Kramers-Kronig relations to match that of high-index tissue components such as lipids. We have demonstrated that our straightforward approach can reversibly render a live mouse body transparent to allow visualization of a wide range of deep-seated structures and activities. This work suggests that the search for high-performance optical clearing agents should focus on strongly absorbing molecules.

中文翻译：

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使用吸收分子在活体动物中实现光学透明性


光学成像在生物学和医学中起着核心作用，但受到活组织中光散射的阻碍。我们报告了一个违反直觉的观察结果，即强吸收分子可以在活体动物中实现光学透明。我们探索了这一观察结果背后的物理学原理，发现当强吸收分子溶于水时，它们可以通过 Kramers-Kronig 关系改变水性介质的折射率，以匹配高折射率组织成分（如脂质）的折射率。我们已经证明，我们简单的方法可以可逆地使活的小鼠身体透明，从而允许可视化各种深层结构和活动。这项工作表明，寻找高性能光学透明化剂应集中在强吸收分子上。