Methylene blue staining

The quality of RNA and transfer can be evaluated by methylene blue staining. This is done by immersing the membrane in 5% acetic acid for 5 min and then in 0.1% methylene blue in 5% acetic acid for 5 min. The membrane is then washed in water, and distinct bands of the 25S (3400 nts), 18S (1800 nts) rRNA, and RNA marker bands should appear. Mark the positions of these with a pencil because the methylene blue staining will disappear during the hybridization. 

FIGURE 18.4 Methylene blue staining of dry-etch (a) and wet-etch (b) microneedle-treated human skin. Disruptions within the stratum corneum indicate microneedle penetration efficiency. 

We have found that turbidity measurements can be used as a routine test to keep track of the yeast cell population. Fermentations routinely were examined microscopically for cell count and viability. We use a 1% methylene blue stain to differentiate viable and dead yeast cells. The dead cells take the stain. 

Methylene blue stains cellular nuclei blue. 

One noteworthy and common feature of these historic hair samples was the abnormally high porosity of the specimens. That virtually all of the inaccessible domain had been degraded was demonstrated by methylene blue staining procedures and by the complete extraction of the drugs by the aqueous wash solutions. 

Cells were exposed to drugs for 3-5 days, allowing for at least two population doublings. Cell numbers were estimated by quantification of protein content of fixed cells by methylene blue staining. Data from Ref. 38. 

For methylene blue staining (Goldman and Bar-Shavit, 1979), adherent cells are fixed 20 min with 0.5% glutaraldehyde in PBS, and stained for 60 min at room temperature with 1% methylene blue solution in 0.1 M borate buffer, pH 8.5. After thorough rinsing in deionized water, extraction of the color from stained cells is done with 0.1 N HCl for 60 min at 37°C in parafilm-sealed plates, and the o.d./well read at 590 nm. The intensity of the color is proportional to the number of cells. 

C. Acridine orange and methylene blue staining prior to and during Northern transfer... 

Hatano, R., N. Kawamura, J. Ikeda, and T. Sakuma. 1992. Evaluation of the effect of morphological features of flow paths on solute transport by using fractal dimensions of methylene blue staining pattern. Geoderma 53 31-44. 

FIGURE 1. Spin rate of yeast (Saccharomyces cerevisiae) in a four-pole rotating electric field as a function of the square of the applied voltage on electrodes with a l-mm gap. The frequency of the applied field was 60 kHz. Measurements of the spin rate ) for cells in various concentrations of sucrose in water. (Squares, circles, triangles, and diamonds designate data for 0, 100, 200, and 300 g sucrose per liter, respectively). The resistivity of the solutions was adjusted to 133 k 2cm. The cells examined were from 10-day-old culture, and were classified as 98% viable by methylene blue stain test. 

The average viability (determined by methylene violet or methylene blue staining) of dried yeast is 20-30% lower than that of freshly propagated yeast. This problem can be accommodated by pitching according to viable cell numbers. 

Methylene blue stains reveal inclusion granules... 

Methylene blue stains reveal bipolar bodies (also... 

The precancerous lesions termed aberrant crypts (AC) have been developed as an early marker for colon carcinogenesis (21). Upon treatment with colon carcinogens mice and rats develop early preneoplastic changes in the crypts of the colon that are easily observable under light microscope after methylene blue staining. Histological examination of AC foci confirmed their dysplasia nature, and are considered precursors to colon cancer (22-25). 

Crystals of uric acid whether originating from pure chemicals urinary sediment or stones, could he stained by uroro— sein, beetroot extract or methylene blue. Staining became possible only at the moment of crystal formation - in statu nas-cendi - i.e. if in the presence of those pigments crystals were formed out of aqueous urate solutions on acidification. 

Meanwhile, the adjacent section was transferred onto a glass slide for conventional histological staining in which the methylene blue staining solution (0.15%, 200 p,l) was deposited onto the tissue section. After 10-s staining, excess stain was washed away with 95% ethanol. 

Ponceau-S is a general stain for cytoplasmic protein and does not distinguish between living, dead, or dying cells that have not undergone autolysis. Because of this problem, Kunkee and Neradt (1974) suggested staining previously examined methylene blue—stained preparations with Ponceau-S because the latter will stain both viable and dead yeast cells. 

O Gonnor-Gox, E., E.M. Mochaba, E.J. Lodolo, M. Majara, and B. Axcell. 1997. Methylene blue staining use at your own risk. Tech. Quart. Master Brew. Assoc. Am. 34 306—312. 

Figure 10.1 Bright-field transmission optical micrograph showing a methylene blue-stained water tree grown from a reamed hole in a sample of medium-voltage polyethylene cable insulation. From...

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