Lee Moosung, Kim Kyoohyun, Oh Jeonghun, Park YongKeun
Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, South Korea.
KAIST Institute for Health Science and Technology, KAIST, Daejeon, 34141, South Korea.
Light Sci Appl. 2021 May 17;10(1):102. doi: 10.1038/s41377-021-00535-4.
A major challenge in three-dimensional (3D) microscopy is to obtain accurate spatial information while simultaneously keeping the microscopic samples in their native states. In conventional 3D microscopy, axial resolution is inferior to spatial resolution due to the inaccessibility to side scattering signals. In this study, we demonstrate the isotropic microtomography of free-floating samples by optically rotating a sample. Contrary to previous approaches using optical tweezers with multiple foci which are only applicable to simple shapes, we exploited 3D structured light traps that can stably rotate freestanding complex-shaped microscopic specimens, and side scattering information is measured at various sample orientations to achieve isotropic resolution. The proposed method yields an isotropic resolution of 230 nm and captures structural details of colloidal multimers and live red blood cells, which are inaccessible using conventional tomographic microscopy. We envision that the proposed approach can be deployed for solving diverse imaging problems that are beyond the examples shown here.
三维（3D）显微镜技术面临的一个主要挑战是在将微观样本保持在其原始状态的同时获取准确的空间信息。在传统的3D显微镜中，由于无法获取侧向散射信号，轴向分辨率低于空间分辨率。在本研究中，我们通过光学旋转样本展示了自由漂浮样本的各向同性显微断层成像。与之前使用具有多个焦点的光镊且仅适用于简单形状的方法不同，我们利用了3D结构光陷阱，其可以稳定地旋转独立的复杂形状微观标本，并在不同的样本方向测量侧向散射信息以实现各向同性分辨率。所提出的方法产生了230纳米的各向同性分辨率，并捕获了胶体多聚体和活红细胞的结构细节，而这些是传统断层显微镜无法获取的。我们设想所提出的方法可用于解决此处所示示例之外的各种成像问题。
