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Utilization of Capsules for Negative Staining of Viral Samples within Biocontainment
Published on: July 19, 2017
Fate of the Escherichia coli capsule during embedding procedures for electron microscopical studies
Abstract:
The effect of the preparation steps of the TEM embedding procedure on the preservation of the Escherichia coli capsule was studied light microscopically. Electron microscopical micrographs did not distinctly reveal capsules whereas simultaneously performed India ink assays clearly revealed predominant capsules both on viable and on chemically fixed bacteria. It is clearly shown that dehydration does not cause extraction or collapse of capsular material to an extent that would explain the invisibility of the capsule on the electron microscopical level, as has hitherto been supposed.
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The simplest type of preparation is the wet mount, in which the specimen is placed in a drop of liquid on the slide. A liquid specimen can be directly deposited on the slide using a dropper. Solid specimens, such as skin scraping, can be placed on the slide before adding a drop of liquid to prepare the wet mount. Sometimes the liquid is simply water, but stains are often added...
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