Staining with uranyl acetate

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). 

Figure 6.13 Electron micrograph of human spleen ferritin viewed at a magnification of x 170 000 after negative staining with uranyl acetate. Both the darkly coloured iron-rich cores and the clear-coloured protein shells are clearly visible. (From Crichton, 1991.)...

Collect sections on acetone-washed copper grids (see Subheading 2.2.) View directly or positive stain with uranyl acetate and lead citrate (sections can be stored in a grid box)... 

Stain with uranyl acetate and lead citrate. 

Fig. 19 TEM image of toroidal micelles from a PAA-PMA-PS triblock copolymer (A). This sample was cast from a solution with 0.1 wt% PAA99-PMA73-PS66 triblock copolymer, a THF water volume ratio of 1 2, and an amine acid molar ratio of 0.5 1 by addition of 2,2-(ethylenedioxy)diethylamine. The cast film was negatively stained with uranyl acetate. A schematical representation of theses micelles is also shown (B). Reprinted with permission from [279], Copyright (2004) American Association for the Advancement of Science...

Lesion in bovine dentin with tubules protruding from degraded intertubular matrix (left degraded matrix right intact matrix). Demineralization in 0.1 M acetic acid pH 4.0, with subsequent exposure to bacterial collagenase. Fixed and demineralized with glutar-dialdehyde-acetic acid, post-fixed with osmium tetroxide ultrathin sections stained with uranyl acetate - lead citrate. 

Figure 1-7 Electron micrograph of a thin section of a young epidermal cell of a sunflower. The tissue was fixed and stained with uranyl acetate and lead citrate. Clearly visible are the nucleus (N), mitochondria (M), chloroplasts (C), a Golgi body dictyosome (G), endoplasmic reticulum, vacuole (V), cell wall, plasmodesmata, and cuticle (upper right, thin dark layer). Micrograph courtesy of H. T. Horner.

Figure 5-13 Electron micrograph of a DNA molecule (from a bacterial virus bacteriophage T7) undergoing replication. The viral DNA is a long ( 14 pm) duplex rod containing about 40,000 base pairs. In this view of a replicating molecule an internal "eye" in which DNA has been duplicated is present. The DNA synthesis was initiated at a special site (origin) about 17% of the total length from one end of the duplex. The DNA was stained with uranyl acetate and viewed by dark field electron microscopy. Micrograph courtesy J. Wolfson and D. Dressier.

Figure 9-4 Electron micrograph (x40,000) of two linked (catenated) cyclic mitochondrial DNA molecules from a culture of human cells. The DNA was stained with uranyl acetate, then shadowed with platinum and palladium atoms in high vacuum to make the molecules easily visible in the electron microscope. (Photograph supplied by Dr. B, S. Hudson and the late Dr. J. Vinograd.)...

Fig. 2. Electron micrographs of negatively stained preparations of E. coli pyrophosphatase. (a and b) Particles stained with sodium silicotungstate (4 g/100 ml, pH 7) the particles in (b) were first fixed in glutaraldehyde (05 g/100 ml). (c) Non-fixed particles stained with uranyl acetate (2 g/100 ml, pH 4).

Swollen fibers of chromatin from the nucleus of the chicken red blood cell. The electron micrograph is enlarged about 325,000x and negatively stained with uranyl acetate. (Micrograph courtesy of A. L. Olins and D. E. Olins.)... 

Figure 3. Electron micrograph of cellulose from beechwood, boiled with 95% TFA for 8 hr. Negative staining with uranyl acetate.

A) Conventionally stained with uranyl acetate and lead citrate for 30min and lOmin, respectively. 

B) Stained with uranyl acetate and lead citrate for 15 sec each in a microwave oven. The ultrastructure is well stained in both cases. Courtesy of Januario C. Estrada. 

For conventional electron microscopy, processing was performed as described in Tsukada et al. (2001) and Yamashima et al. (2003). Small specimens of hippocampus were fixed with 2.5% glutaraldehyde for 2 h and subsequently with 1% osmium tetroxide in TBS for 1 h at 4°C, dehydrated in ascending ethanol series, incubated in propylene oxide (2 x 15 min) and finally embedded in epon-araldite mixture. Usually, between four and eight semithin (1 pm) sections were stained with tolui-dine blue for the light microscopic observation. After trimming upon observation of toluidine blue staining, the ultrathin sections were stained with uranyl acetate (10 min) and lead citrate (5 min) for the electron microscopic observation (JEM H-600, Hitachi, Tokyo). 

Figure 9.2 Transmission electron micrograph of Cowpea mosaic virus particles negatively stained with uranyl acetate. The scale bar is lOOnm.

Fig. 2. Electron micrograph of vanadocytes from Ascidia nigra. Cells were fixed in 2.5% glutaral-dehyde in 0.15 M HC1, followed by 1% osmium tetroxide, pH 7.6. The sections were stained with uranyl acetate N = nucleus, PM = plasmalemma, V = vacuoles (very electron dense presumably because of reduction of osmium tetroxide by V(III).)...

Tonoiilament Assembly. The available information suggests that keratin is sequentially assembled around primary fibers that originate within the attachment plates of desmosomes (27). The dense cores of 50-A filaments (stained with uranyl acetate) represent such fibers (64, 84). These cores and their surrounding fibrous protein probably contain about 50% a helix (71). They contain even less sulfur (32, 64) than the high methionine (1.4 residues/100 amino acid residues), low cystine (1.1 residues/100 amino acid residues) fraction obtained by Baden after partial enzymatic hydrolysis (82). Studies with tritiated amino acids suggest that basal cells preferentially incorporate methionine, leucine, and phenylalanine within their elements (73, 74). In Figure 13A the primary rope is identified with the 35-A diameter of the smallest filaments that have been isolated (32). 

Fig. 7 TEM image of aggregates of PAELi-fc-PLPheg negatively stained with uranyl acetate specimen was prepared by deposition of a drop of a 0.2 wt % polymer solution on a carbon-coated copper grid, drawing-off the solution with filter paper, and subsequent drying in vacuo. Reprinted with permission from [42], copyright (1997) Hiithig Wepf...

Specimens for electron microscopy were prepared as thin cross-sections and stained with uranyl acetate and lead citrate. A JEOL lOOB electron microscope was used to obtain the electron micrographs. Reconstruction of sections of these micrographs by Fourier filtration methods was done in collaboration with Dr. J. Frank of New York State Department of Health, Albany, N.Y. 

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