Expansion microscopy enables conventional diffraction limit microscopy to achieve super-resolution imaging. However, the enlarged tissue lacks an objective lens with sufficient working distance that can image tissues with whole-brain-scale coverage. Here, we present expansion tomography (ExT) to solve this problem. We have established a modified super-absorbent hydrogel (ExT gel) that possesses high mechanical strength and enables serial sectioning. ExT gel enables tissue and cell imaging and is compatible with various fluorescent labeling strategies. Combining with the high-throughput light-sheet tomography (HLTP) system, we have shown the capability of large volume imaging with nanoscale resolution of mouse brain intact neuronal circuits. The ExT method would allow image samples to support super-resolution imaging of intact tissues with virtually unlimited axial extensions.

中文翻译：

---

用于具有纳米级分辨率的大体积组织成像的扩展断层扫描

膨胀显微镜使传统的衍射极限显微镜能够实现超分辨率成像。然而，扩大的组织缺乏具有足够工作距离的物镜，可以对具有全脑尺度覆盖的组织进行成像。在这里，我们提出了扩展断层扫描（ExT）来解决这个问题。我们已经建立了一种改良的超吸收水凝胶（ExT 凝胶），它具有高机械强度并能够连续切片。ExT 凝胶可实现组织和细胞成像，并与各种荧光标记策略兼容。结合高通量光层断层扫描 (HLTP) 系统，我们已经展示了大容量成像的能力，以及小鼠大脑完整神经元回路的纳米级分辨率。