Methyl green

Methyl green, hexamethylpararosaniline hydroxymethylate (component of mixed indicator) dissolve 0.1 g in 100 mL alcohol when used with equal parts of hexamethoxytriphenyl carbinol gives color change from violet to green at a titration exponent (pi) of 4.0. 

Methyl-gallusathersaure, /. 0-methylgallic acid, methyl ether of gallic acid, -grtin, n. methyl green, -hydriir, n. methyl hydride, methane. 

Figure 7.7 Separation of ethynyl estrogens on silica gel 60 HPTLC plates using two 15-min developments in the solvent system hexane-chloroform-carbon tetrachloride-ethanol (7 18 22 1 v/v). Identification O methyl green (lane marker) 1 17a-ethynylestradiol ...

The relentless search for new and cheaper colors produced its own casualties. The Empress aldehyde green was swept aside by iodine green, methyl green, malachite green, and so on. Natural dyes were also falling by the wayside. Canary Island farmers who raised cacti for tiny cochineal beetles were bankrupted 70,000 of the dried beetles made only 1 pound of crimson dye, and the new synthetic colors were much cheaper. 

Convenient ready-to-use nuclear counterstains in blue, green or red colour like Hematoxylin, Methyl Green and Nuclear Fast Red are available from Vector Laboratories (http //www.vectorlabs.com/), DAKO (http //www.dako.com/) and some other vendors, but if you are interested in preparing nuclear counterstains yourself, good and thorough procedures may be found in textbooks of Polak and Van Noorden (1997) and Renshaw (2007) or on the website http //www.ihcworld. com/counterstain solutions.htm. 

The microsomal fraction was first obtained by Claude in 1943. In addition to lipid in the fraction, he noted the presence of RNA-rich granules, consistent with reports from Brachet that cytoplasm stained for RNA by the methyl-green/pyronin procedure. Glucose-6-phos-phatase was a prominent enzyme when the fraction was prepared from liver. Since density gradient sedimentation showed G-6-P-ase was absent from mitochondria and lysosomes, it was used as a marker for liver microsomes. 

Nuclei were first isolated by Miescher (1869) from pus cells recovered from discarded surgical bandages. The principle constituent—a phosphorus-rich material then called nuclein—was stained by methyl green. A few years later salmon sperm were shown to contain a phosphorus-rich acidic compound—the nucleic acid—and a basic protein protamine. Further work by Kossel, Levene,... 

There are times when two color assays may be required. This can be accomplished by altering the enzyme system used for one of the assays or the chromogen used for one of the assays if the enzymes are not altered. Perhaps the easiest method is to alter the color product of the DAB chromogen for one of the assays. This can be done be adding a heavy metal compound such as cobalt or nickel to the dilute solution (9). The resultant precipitate will be blue to black, not brown. It is helpful in this circumstance to use a Methyl Green counterstain, which will enhance the black precipitate and avoid the confusion of color seen with some other counter stains. 

As another alternative, 1 mL of 1% cobalt or nickel chloride can be added to the DAB solution prior to slide incubation, and the resultant precipitate will be dark blue to black, not brown (7). This can increase the overall sensitivity of the reaction, but it is not popular because of the different color counterstain that is usually required. A 5% solution of Methyl Green used as a counterstain for 5 min provides enough contrast to the blue to be a good background for interpreting assays with a nuclear location. 

Connterstain in hematoxylin. Other counterstains, such as Methyl Green or eosin, may be used (see Note 20). 

Fig. 1. Photomicrographs of a reactive lymph node follicle with germinal center (G), mantle (M), and surrounding paracortex (P) immunostained using the avi-din-biotin complex technique. (Top) Follicle stained with an antibody specific to B-cells, B1 (CD20) (Coulter Immunology, Hialeah, FL), counterstained with Methyl Green. (Bottom) Parallel section of the same follicle stained with an antibody specific to T-cells, Leu 4 (CDS) (Becton-Dickinson, Mountain View, CA). Scale bar = 100 p.

Competitive adsorption on sepiolite clay of a monovalent dye (e.g., methyl green or methyl blue) and of the divalent organo-cationic herbicides diquat and paraquat was studied by Rytwo et al. (2002). To evaluate a possible competitive adsorption between the two organic compounds, separate aqueous solutions of each cation were used and adsorption isotherms were obtained. Fig. 8.27 shows the amount of diquat, paraquat, and methyl green adsorbed on sepiolite as a function of total added divalent cation. It may be observed that, when the added amounts were lower than the cation exchange capacity of the sepiolite (O.Mmol kg ), aU cations were completely adsorbed. 

Fig. 8.27 Adsorption isotherms of methyl green (MG), diquat (DQ) and paraquat (PQ) on sepio-Ute. Reprinted from Rytwo G, Tropp T, Serban C (2002) Adsorption of diquat, paraquat and methyl green on sepiolite experimental results and model calculations. Applied Clay Sci 20 273-282. Copyright 2002 with permission of Elsevier...

DMSO, Sodium azide, DINA, Methylene chloride. Sodium sulfate. Activated alumina Methyl green. Sodium picramate. Hydrochloric acid. Sodium nitrate... 

Chloronaphthol. Incubate the slides for 8 min The product is blue and soluble in xylene We do not know a suitable counterstain, hemalum being blue is unsuitable, and methyl green is water-soluble. Mount in glycerin jelly... 

Tetramethyl benzidine. Incubate for 15 min. The product is blue, and stable in xylene and alcohols. Counterstain with methyl green, and mount in DPX. 

Brilliant green, malachite green, methyl green. Victoria green, setoglaucine, new fast green, etc. Decolorised, Colour does not return On exposure to air, but is restored by persulphate Trxphenyl-mathane 1 Class... 

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