Transmission electron microscopy staining

Draget KI, Myhre S, Ostgaard K. Plant protoplast immobilized in calcium alginate. A simple method of preparing fragile cells for transmission electron microscopy. Stain Technol 1988 63 159-163. 

Wilkinson, K.J., Stoll, S. and Buffle, J. (1995) Characterization of NOM-colloid aggregates in surface waters coupling transmission electron microscopy staining techniques and mathematical modelling. Fresenius J. Anal. Chem., 351, 54—61. 

Paine et al. [99] tried different stabilizers [i.e., hydroxy propylcellulose, poly(N-vinylpyrollidone), and poly(acrylic acid)] in the dispersion polymerization of styrene initiated with AIBN in the ethanol medium. The direct observation of the stained thin sections of the particles by transmission electron microscopy showed the existence of stabilizer layer in 10-20 nm thickness on the surface of the polystyrene particles. When the polystyrene latexes were dissolved in dioxane and precipitated with methanol, new latex particles with a similar surface stabilizer morphology were obtained. These results supported the grafting mechanism of stabilization during dispersion polymerization of styrene in polar solvents. 

Chen S., Cao T., and Jin Y., Ruthenium tetraoxide staining technique for transmission electron microscopy of segmented block copoly(ether-ester), Polym. Commun., 28, 314, 1987. 

FIGURE 5.3 Electron micrographs of whey protein isolate (WPI). Scanning electron microscopy of dry WPI powder (A). Transmission electron microscopy of WPI stained with uranyl acetate (B) nonextruded WPI Paste (40% moisture) and (C) extruded texturized WPI (100 °C, 40% moisture) (Onwulata et ai, 2003a). 

III. Transmission electron microscopy of radish seeds Transmission electron microscopy (TEM) of radish seeds was done as listed below For TEM preparations, the specimens after fixation and dehydration, were embedded in Epon 812 resin (Luft, 1961). Thick sections (ca. 1mm each) were stained with 0.1% toluidine blue and observed with a Zeiss light photomicroscope. Thin sections, obtained with a diamond knife on a Supernova microtome, were sequentially stained at room temperature with 2% uranyle acetate (aqueous) for 5 min and by lead citrate for 10 min (Reynolds, 1963). Ultrastructural studies were made using a Philips CM12 transmission electrone microscope (TEM) operated at 80 KV. 

After polymerization was complete, transmission electron microscopy was carried out on thin sections of the 10/90 and 20/80 compositions. Confirming the optical micrographs, the polystyrene phase was continuous for the fully reacted product. As illustrated in Figure 5 for the 10/90 system, the oil phase (stained dark) contains a considerable amount of occluded polystyrene. For the 20/80 system, data not shown, dual phase continuity was found. The polystyrene phase was relatively pure, but the oil-rich phase had much occluded... 

Figure 2. Morphology of various cross-polybutadiene-in/er-cross-polystyrene sequential IPNs and graft copolymers via transmission electron microscopy. The double bonds in the polybutadiene phase are stained dark with osmium tetroxide. (Reproduced from ref. 15. Copyright 1976 American Chemical Society.)...

Tobacco primary cell wall and normal bacterial Acetobacter xylinum cellulose formation produced a 36.8 3A triple-stranded left-hand helical microfibril in freeze-dried Pt-C replicas and in negatively stained preparations for transmission electron microscopy (TEM). A. xylinum growth in the presence of 0.25 mM Tinopal disrupted cellulose microfibril formation and produced a... 

Visualization of the micromorphology with transmission-electron microscopy (TEM) on ultrathin cuts after staining with osmium tetraoxide... 

Figure 14.10 Self-assembly of peptide-amphiphiles into nanofibers (a) a peptide amphi-phile molecule with five distinct regions designed for hydroxyapatite mineralization, (b) a schematic of molecular self-assembly, and (c) a negatively stain transmission electron microscopy image of the nanofibers. Reprinted from Hartgerink et al. (2001). Copyright 2001 American Association for the Advancement of Science.

Manara, G C, Ferrari, C, Torresani, C., Sansoni, P, and De Panfilis, G. (1990) The immunogold-silver staining approach in the study of lymphocyte subpopula-tions in transmission electron microscopy. J Immunol Methods 128, 59-63... 

One major problem of all these techniques is the sensitivity in the parameter selected to detect the presence of inhomogeneities. With visible light for example, inhomogeneous samples can appear transparent if the difference in the refractive index between the phases is less than 0.01. Staining (in the case of transmission electron microscopy, TEM), or chemical etching (in the case of scanning electron microscopy, SEM), can be helpful in revealing the structure. 

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