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The Effects of Electron Beam Exposure Time on Transmission Electron Microscopy Imaging of Negatively Stained Biological Samples

  • Kim, Kyumin (Taejon Christian International School) ;
  • Chung, Jeong Min (Department of Biochemistry, College of Natural Sciences, Kangwon National University) ;
  • Lee, Sangmin (Department of Biochemistry, College of Natural Sciences, Kangwon National University) ;
  • Jung, Hyun Suk (Department of Biochemistry, College of Natural Sciences, Kangwon National University)
  • Received : 2015.08.06
  • Accepted : 2015.09.17
  • Published : 2015.09.30

Abstract

Negative staining electron microscopy facilitates the visualization of small bio-materials such as proteins; thus, many electron microscopists have used this conventional method to visualize the morphologies and structures of biological materials. To achieve sufficient contrast of the materials, a number of imaging parameters must be considered. Here, we examined the effects of one of the fundamental imaging parameters, electron beam exposure time, on electron densities generated using transmission electron microscopy. A single site of a negatively stained biological sample was illuminated with the electron beam for different times (1, 2, or 4 seconds) and sets of micrographs were collected. Computational image processing demonstrated that longer exposure times provide better electron densities at the molecular level. This report describes technical procedures for testing parameters that allow enhanced evaluations of the densities of electron microscopy images.

Keywords

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