Ogura Toshihiko
Neuroscience Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan.
Biochem Biophys Res Commun. 2008 Dec 5;377(1):79-84. doi: 10.1016/j.bbrc.2008.09.097. Epub 2008 Oct 1.
The contrast of biological samples in scanning electron microscopy (SEM) is very weak. To examine a biological specimen by SEM, many steps and/or special equipment are required to prepare the sample. Here, we describe a method using an unstained biological sample under a 40 nm carbon film to give a high contrast image, where the image is detected by the secondary electron (SE) signal at a low accelerating voltage of 1.5 kV. Under these conditions, it is hard to detect a direct signal from a biological specimen. The high contrast image is created by the SEs from the lower surface of the thin carbon film. Therefore, the damage to the sample from the electron beam is very low. Our method can be utilized to observe various biological samples of bacteria, viruses, and protein complexes.
扫描电子显微镜（SEM）中生物样品的对比度非常低。要通过SEM检查生物标本，需要许多步骤和/或特殊设备来制备样品。在此，我们描述一种方法，即在40纳米碳膜下使用未染色的生物样品以获得高对比度图像，该图像通过在1.5 kV的低加速电压下的二次电子（SE）信号进行检测。在这些条件下，很难检测到来自生物标本的直接信号。高对比度图像是由来自薄碳膜下表面的二次电子形成的。因此，电子束对样品的损伤非常低。我们的方法可用于观察细菌、病毒和蛋白质复合物等各种生物样品。
