London Centre for Nanotechnology, University College London, , 17-19 Gordon Street, London WC1H 0AH, UK.
Philos Trans A Math Phys Eng Sci. 2014 Jan 27;372(2010):20130144. doi: 10.1098/rsta.2013.0144. Print 2014 Mar 6.
Scanning electron microscopy (SEM) is used to evaluate potential chromosome preparations and staining methods for application in high-resolution three-dimensional X-ray imaging. Our starting point is optical fluorescence microscopy, the standard method for chromosomes, which only gives structural detail at the 200 nm scale. In principle, with suitable sample preparation protocols, including contrast enhancing staining, the surface structure of the chromosomes can be viewed at the 1 nm level by SEM. Here, we evaluate a heavy metal nucleic-acid-specific stain, which gives strong contrast in the backscattered electron signal. This study uses SEM to examine chromosomes prepared in different ways to establish a sample preparation protocol for X-rays. Secondary electron and backscattered electron signals are compared to evaluate the effectiveness of platinum-based stains used to enhance the contrast.
扫描电子显微镜（SEM）用于评估潜在的染色体制备和染色方法，以应用于高分辨率三维 X 射线成像。我们的起点是光学荧光显微镜，这是染色体的标准方法，只能在 200nm 尺度上提供结构细节。原则上，通过适当的样品制备方案，包括增强对比度的染色，可以通过 SEM 在 1nm 水平上观察染色体的表面结构。在这里，我们评估了一种重金属核酸特异性染色剂，它在后向散射电子信号中产生强烈的对比。这项研究使用 SEM 检查了以不同方式制备的染色体，以建立用于 X 射线的样品制备方案。比较了二次电子和背散射电子信号，以评估用于增强对比度的基于铂的染色剂的有效性。
