Similar to our longer-wavelength light-microscopy brethren, electron microscopists are faced with a growing array of instruments for specimen preparation and imaging. Because of the short wavelength of the electron beam (100,000-fold shorter than photons in visible light), TEM can achieve subnanometer resolution-well below that of even the highest-resolution light microscopes, ∼20 nm. The most frequently used TEM application in cell biology entails imaging stained thin sections of plastic-embedded cells by passage of an electron beam through the sample such that the beam will be absorbed and scattered, producing contrast and an image (see Table 1 for a definition of terms). Transmission electron microscopy (TEM) has been an important technology in cell biology ever since it was first used in the early 1940s.
0 Comments
Leave a Reply. |