Applied Physics, Northwestern University, Evanston, IL, 60208, USA.
X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, IL, 60439, USA.
Sci Rep. 2017 Mar 27;7(1):445. doi: 10.1038/s41598-017-00569-y.
X-ray microscopy can be used to image whole, unsectioned cells in their native hydrated state. It complements the higher resolution of electron microscopy for submicrometer thick specimens, and the molecule-specific imaging capabilites of fluorescence light microscopy. We describe here the first use of fast, continuous x-ray scanning of frozen hydrated cells for simultaneous sub-20 nm resolution ptychographic transmission imaging with high contrast, and sub-100 nm resolution deconvolved x-ray fluorescence imaging of diffusible and bound ions at native concentrations, without the need to add specific labels. By working with cells that have been rapidly frozen without the use of chemical fixatives, and imaging them under cryogenic conditions, we are able to obtain images with well preserved structural and chemical composition, and sufficient stability against radiation damage to allow for multiple images to be obtained with no observable change.
X 射线显微镜可以用于对未切片的、处于天然水合状态的完整细胞成像。它补充了电子显微镜在亚微米厚样本上的更高分辨率，以及荧光显微镜的分子特异性成像能力。我们在这里描述了第一个使用快速、连续的冷冻水合细胞的 X 射线扫描，用于同时以亚 20nm 的分辨率进行相衬透射成像，具有高对比度，以及以亚 100nm 的分辨率对扩散和结合离子进行去卷积的 X 射线荧光成像，而无需添加特定的标记。通过使用快速冷冻而不使用化学固定剂的细胞进行工作，并在低温条件下对其进行成像，我们能够获得具有良好保存的结构和化学成分的图像，并且对辐射损伤具有足够的稳定性，可以获得多张图像而没有可观察到的变化。
