Specimen preparation for electron microscopy: an overview

The electron microscope uses a beam of electrons to create an image of the specimen. It is capable of much higher magnifications and has a greater resolving power than a light microscope. For EM, the ultrastructure must be preserved as close to the in vivo situation to the maximum extent possible. This is done by either chemical or cryofixation. The ultrastructural examination of tissues, cells and microorganisms is important in diagnostic pathology as well as biologic research. There are two types of electron microscope viz., Transmission electron microscope (TEM) and Scanning electron microscope (SEM).