Cole R W, Parsons D F
High-Voltage Electron Microscope Biotechnology Resource, Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany 12201.
Cell Biophys. 1988 Oct;13(2):133-40. doi: 10.1007/BF02796976.
In the past, biological sections ranging in thickness from 0.10- to 0.50-micron have usually been examined with high-voltage (greater than 500 kV) electron microscopes (HVEM). Now investigators are increasingly using intermediate voltage (200-500 kV) electron microscopes (IVEM), which are more readily available and demand less maintenance. In a study of "typical" plastic-embedded, stained sections of mouse liver ranging from 0.10 to 1.0 micron thick, we determined the resolution obtainable at 100, 200, and 1000 kV. At all three accelerating voltages the resolution (2.7 nm) for 0.10-micron sections was limited only by the sections stain granularity. For 0.25-micron thickness the resolutions were 5.8, 3.1, and 3.1 nm at 100, 200, and 1000 kV, respectively. The maximum usable thickness at 200 kV with resolution sufficient to resolve membranes clearly was between 0.75 and 1.0 micron, depending on the magnification. Resolution at 100 kV was adequate for screening sections up to 1.0-micron thick for preparation defects prior to examination with an IVEM or HVEM.
过去，厚度在0.10至0.50微米之间的生物切片通常用高压（大于500 kV）电子显微镜（HVEM）进行检查。现在，研究人员越来越多地使用中压（200 - 500 kV）电子显微镜（IVEM），这种显微镜更容易获得且维护需求较少。在一项对厚度从0.10到1.0微米的小鼠肝脏“典型”塑料包埋、染色切片的研究中，我们测定了在100、200和1000 kV下可获得的分辨率。在所有这三种加速电压下，0.10微米切片的分辨率（2.7纳米）仅受切片染色颗粒度的限制。对于0.25微米厚度的切片，在100、200和1000 kV下的分辨率分别为5.8、3.1和3.1纳米。在200 kV下，具有足以清晰分辨膜的分辨率的最大可用厚度在0.75至1.0微米之间，这取决于放大倍数。在100 kV下的分辨率足以在使用IVEM或HVEM检查之前，对厚度达1.0微米的切片进行制备缺陷筛查。
