Electron microscopy overview

The history of EM (for an overview see table Bl.17,1) can be interpreted as the development of two concepts the electron beam either illuminates a large area of tire sample ( flood-beam illumination , as in the typical transmission electron microscope (TEM) imaging using a spread-out beam) or just one point, i.e. focused to the smallest spot possible, which is then scaimed across the sample (scaiming transmission electron microscopy (STEM) or scaiming electron microscopy (SEM)). In both situations the electron beam is considered as a matter wave interacting with the sample and microscopy simply studies the interaction of the scattered electrons. 

I. Goldstein, eds.) Plenum Press, 1979. A good overview of analytical electron microscopy. 

Seeing the surface of a catalyst, preferably in atomic detail, is the ideal of every catalytic chemist. Unfortunately, optical microscopy is of no use for achieving this, simply because the rather long wavelength of visible light (a few hundred nanometers) does not enable features smaller than about one micrometer to be detected. Electron beams offer better opportunities. Development over the past 40 years has resulted in electron microscopes which routinely achieve magnifications on the order of one million times and reveal details with a resolution of about 0.1 nm [1], The technique has become very popular in catalysis, and several reviews offer a good overview of what electron microscopy and related techniques tell us about a catalyst 12-6],... 

Each specimen was dehydrated, infiltrated and embedded in Technovit based methylmethacrylate. One section was cut and around in preparation for scanning electron microscopy (SEM). In each case, three overview photos were necessary and four high magnification fields (40X) were photographed and digitized. These fields were later analyzed for volume fraction of soft tissue, bone... 

Characterization is the foundahon for the development and commercialization of new zeolites and zeolite-containing catalysts and adsorbents. Chapter 4 provides an overview of the most commonly employed characterization techniques and emphasizes the uhlity and limitations of each of these methods. An example is provided as to how a multi-technique characterization approach is necessary in order to determine the structure of a newly invented zeolite. Techniques covered in this chapter include X-ray powder diffraction, electron microscopy, infrared (IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and physical/ chemical methods. 

Hodges, G M., Southgate, J, and Toulson, E. C (1987) Colloidal gold-a powerful tool in S E. M. immunocytochemistry an overview of bioapplications. Scanning Electron Microscopy 1, 301—318. 

In this chapter, we provide an overview of our recent efforts to develop a fundamental science base for the design and preparation of optimal lipid-based carriers of DNA and siRNA for gene therapy and gene silencing. We employ synthesis of custom multivalent lipids, synchrotron X-ray diffraction (XRD) techniques, optical and cryo-electron microscopy, as well as biological assays in order to correlate the structures, chemical, and biophysical properties of cationic liposome (CL)-NA complexes to their biological activity and to clarify the interactions between CL-NA complexes and cellular components. Earlier work has been reviewed elsewhere [1-7] and will not be covered exhaustively here. 

In this overview, we will first discuss how transmission electron microscopy (TEM) techniques can be used to determine the presence or absence of intergranular amorphous phases at interphase boundaries in structural... 

To better understand the structure, function, and dynamics of the endogenous lipid matrix of the stratum corneum intercellular space some general principles of lipid phase behavior, dynamics, and structural organization may represent a useful starting point. Further follows a short overview of some basic physico-chemical principles that may be of relevance for stratum corneum lipid research, followed by a presentation of the new technique cryo-transmission electron microscopy of fully hydrated vitreous skin sections and how this technique recently has been applied to the study of the structural organization and formation of the lipid matrix of the stratum corneum intercellular space. 

Staining of consecutive sections with histochemical reagents for protein and antibodies against myrosinase showed that myrosin cells actually contain myrosinase (Fig. 4.2D,E).18,43,44 By electron microscopy immunogold labelling studies, the enzyme was localized to the interior of the vacuoles of the myrosin cells (Fig. 4.2F).18,40,41 It has also been shown by several in situ hybridization experiments that myrosinase transcripts are located in these cells (Fig. 4.2G),6 demonstrating that the cellular localization of myrosinase is due to transcriptional regulation and not to a transport process. No evidence for transport of myrosinase currently exists. These methods for detection and identification of myrosin cells and myrosinase expression are illustrated (Fig. 4.2). For a historical overview of myrosinase localization studies, see Bones and Rossiter.45... 

The study of chondrite matrices is both time-consuming and challenging, principally because of the fine-grained characteristics of the material. Transmission electron microscopy (TEM) has been the analytical technique of choice, because it provides textural and mineralogical information from the micron down to the nanoscale. Here, we briefly overview the main textural and mineralogical characteristics of matrices in very un-equilibrated chondrites, focusing principally on the carbonaceous chondrites. 

Fig. 3. The structure of whipped cream as determined by scanning electron microscopy. A. Overview showing the relative size arxf prevalerKe of air bubbles (a) and fat globules (/) bar = 30 pm. B. Internal structure of the air bubble, showing the layer of partially coalesced fat which has stabilized the bubbly bar = 5 pm. C. Details of the partially coalesced fat layer, showing the interaction of the irxfividual fat globules. Bar = 3 pm (Ref. 16).

The book by Sawyer and (irubb" provides a more detailed account of electron microscopy of polymers and in particular, an excellent overview of the different sample preparation techniques that have been devised. 

The most comprehensive overview of electron microscopy and diffraction, especially the geometry of electron diffraction patterns, is ... 

Detailed overviews on test methods and vimses detected are provided. For retro-vimses and other endogenous vimses, electron microscopy, infectivity assays or reverse transcriptase assays are proposed. Non-endogenous or adventitious vimses may be detected by suitable in vitro or in vivo assays or (in case of rodent cell fines) by a corresponding antibody production test in the respective species. Other virus-specific tests might be useful alternatives. 

Kalab, M. (1979). Scanning electron microscopy of dairy products. An overview. Scanning Electron Microsc. Ill, 261-271. 

Steven A.C. (1997). Overview of Macromolecular electron microscopy an essential tool in protein structural analysis. Current Protocols in Protein Science. 17.2.1—17.2.29. 

The article by Brown et al (1) provides a good overview of chain segregation as shown by electron microscopy and scattering techniques. 

See also-. Archaeometry and Antique Analysis Dating of Artifacts. Electrophoresis Overview. Fourier Transform Techniques. Gas Chromatography Pyrolysis. Mass Spectrometry Overview. Microscopy Techniques Light Microscopy Scanning Electron Microscopy. Thin-Layer Chromatography Overview. X-Ray Fluorescence and Emission Energy Dispersive X-Ray Fluorescence. 

Spectrometry Overview. Mercury. Microscopy Techniques Scanning Electron Microscopy X-Ray Microscopy. Particle Size Analysis. Polychlorinated Biphenyls. Polycyclic Aromatic Hydrocarbons Environmental Aj li-cations. Radiochemical Methods Overview. Sample Handling Sample Preservation. Sampling Theory. Surface Analysis Auger Electron Spectroscopy. Tin. X-Ray Absorption and Diffraction Overview. X-Ray Fluorescence and Emission Energy Dispersive X-Ray Ruores-cence Particle-Induced X-Ray Emission. 

See also Microscopy Overview. Microscopy Techniques Light Microscopy Electron Microscopy ... 

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