Ethanol 2-mercaptoethanol

The presence of Individual chains In a hemoglobin variant can also be demonstrated by electrophoresis at alkaline pH after the protein has been dissociated Into Its subunits through exposure to 6 M urea In the presence of 3-mercaptoethanol. The buffer is either a barbital buffer or a tris-EDTA-boric acid buffer, pH 8.0 - 8.6, and contains 6 M urea and 3-niercapto-ethanol. Dissociation of the hemoglobin Into subunits Is best accomplished In a mixture of 1 ml 10 g% Hb (or whole hemolysate), 4 ml 6 M urea barbital or tris-EDTA-boric acid buffer, and 1 to 1.5 ml 3-mercaptoethanol. After 30 minutes to 1 hour the sample Is subjected to cellulose acetate or starch gel electrophoresis. Each chain has a specific mobility and an alteration In electrophoretic mobility easily Identifies the abnormal chain. 

All in aqueous solution at 25°C unless otherwise noted equilibrium constants have dimensions of M. Various alkane thiols, of similar equilibrium reactivity. Methylamine or a primary alkyl amine of similar reactivity. Dimethylamine or a secondary alkyl amine of similar reactivity °Reference 30. Reference 14. RSH is mercaptoethanol. Reference 31. Reference 32. Reference 33. Reference 21. RSH is ethanethiol " Reference 34. Reference 35. Reference 36. Reference 37. RSH is 2-methoxyethanethiol. Reference 38. Reference 39. Reference 40. Reference 23. Reference 41. Reference 31. Reference 42. Reference 5. Reference 43. In ethanol. Reference 44. Reference 45. Reference 46. RNKj is n-butylamine. "Reference 47. 

Merino-Merino et al. [32] used the OPA reagent (o-phthaldehyde condensed with 2-mercaptoethanol) to separate penicillamine enantiomers after their derivatization. Racemic and (/q-penicillamine were dissolved in aqueous 0.5 M NaOH, and treated with the derivatizing solution (methanolic o-phthaldehyde and 2-mercaptoethanol in 0.4 M potassium borate buffer solution of pH 10). The reaction mixture was set aside for 2 min at room temperture, whereupon a portion of solution was analyzed by HPLC. The method used a Cyclobond column (25 cm x 4.6 mm) maintained at 5 °C, a mobile phase of ethanol/1% triethylammonium acetate (1 1 pH 4.5) eluted at... 

The cells are lysed in a buffer containing strong chaotropic reagents such as guanidine thiocyanate and 2-mercaptoethanol, which completely denatures any ribonuclease present. The supernatant is then placed on a cushion of CsCl (5.7 mol l-1) and centrifuged at 100000 g for 18 h. The RNA passes through the CsCl and is pelleted, while the DNA and protein remain in the aqueous solution. The RNA pellet is dissolved in buffer and concentrated by precipitation in cold ethanol. 

Chemisorption was accomplished by immersion for 12 hours in a 1 mM solution of either mercaptoethanol or hexadecylthiol the solvent was absolute ethanol. 

Method (manual). An aliquot portion (0.1 ml) of effluent containing the amino acid is mixed with 3 ml of a solution containing 1.5 ml of o-phthalaldehyde (10 mg/ml in ethanol), 90 ml of sodium tetraborate buffer (0.05 M, pH 9.5) and 1.5 ml of a solution of 2-mercaptoethanol (5 mg/ml) in ethanol. The latter reagent should be freshly prepared each day. The reaction mixture is permitted to stand for 5 min and the intensity of fluorescence is measured in a fluorimeter (340-nm excitation, 455-nm emission). The buffered reagent may be also useful as a spray reagent for amino acids separated by TLC, although such an investigation has not been reported. 

The hydroxylated surfaces are reacted with epichlorohydrin (0.5 M) in solution D, for 4 h at room temperature. The surface is washed sequentially with water, ethanol, and water. Solution E (5 mL) containing each amino-ethanethiol-activated ligand (5 mM) and mercaptoethanol (5 niA/) is hand spotted on the gold surface in predefined linear positions and reacts for 12 h at room temperature, after which the slide is immersed in DMF (50 mL) to remove unbound ligands. 

FIGURE 5.11 Chromatogram of a dichloromethane extract of a Touriga Nacional (1999 vintage) and of a 20-year-old tawny port wine 1, dimethyl sulfide 2, internal standard, ethyl (methylthio)acetate 3, 2-mercaptoethanol 4, 2-(methylthio)ethanol 5,... 

In contrast to their previous report, Bayer et al. (5) recently reported the requirement of Na2S in reconstituted spinach ferredoxin from a, a -dipyridyl-treated apoferredoxin in the presence of ferrous ion and 2-mercaptoethanol. In this report, they mentioned that, if 2-mercapto-ethanol is not purified before use, the addition of Na2S is not required. Therefore, one can assume that unpurified 2-mercaptoethanol contains H2S. We checked for the presence of H2S in once distilled 2-mercapto-ethanol by gas chromatography. The presence of H2S in samples of 2-mercaptoethanol could not be detected by this method. Since an excess amount of 2-mercaptoethanol is required for the reconstitution experiment, minute contamination of H2S in the sample may serve for the labile sulfur source, or H2S may be produced from 2-mercaptoethanol under the conditions of the reaction. 

Kochhar et al. (1989) characterized an assay for glutamate decarboxylase activity. Glutamate and 4-aminobutyrate were separated on a Nucle-osil Q column. The mobile phase was 13 mAf trifluoroacetate and 1 mAf 1-octanesulfonate. Detection was by postcolumn derivatization with o-phthaldialdehyde reagent (1 mL/min) mixed with the column eluate (also 1 mL/min). The Teflon reaction coil (3 m x 0.3 mm) was kept at room temperature. The o-phthaldialdehyde reagent was prepared by dissolving 800 mg of o-phthaldialdehyde in 20 mL of ethanol plus 2.5 mL of 2-mercaptoethanol and mixing with 980 mL of 0.4 Af sodium borate (pH 9.7) and 3 mL Brij 35. The fluorometer was set to give excitation at 350 nm and emission was measured at 450 nm. 

The reaction mixture used to monitor enzyme purification contained 35 mM potassium phosphate (pH 7.4), 2.5 mM magnesium chloride, 10 mM 2-mercaptoethanol, 200 iM NADPH, 20 /xM 5-fluorouracil, and enzyme solution. The final volume was 2.0 mL. At various reaction times, 350 fiL of reaction sample was taken and added into an equal volume of ethanol. After filtering, an aliquot was analyzed by HPLC. 

Blister 2-Chloroethylethylsulfide, 1,4-thioxane, 1,4-dithiane, 2-mercaptoethanol, ethanol, benzene, toluene, xylene, chloroform... 

SYNS EMERY 5791 1-ETHANOL-2-THIOL 2-HYDROXY-l-ETHANETHIOL 2-HYDROXYETHYL MERCAPTAN 2-ME MERCAPTOETHANOL P-MERCAPTOETHANOL MONOTfflOETHYLENE-GLYCOL 2-THIOETHANOL TfflOGLYCOL (DOT)... 

Peptide Modification lodination was carried out on a stainless steel probe target by adding 0.1 % aq. I2 (1 pi) to the dried peptide (ca. 1 pmol). The reaction was stopped after 1 minute by addition of ascorbic acid and the MALDI matrix, a-cyano cinnamic acid in excess. Esterification with ethanol was carried out using the method of Hunt et al. (15), where an acetylchloride and ethanol solution (1 6, v v) was added (5 pi) to the peptide dried in a microcentrifuge tube (ca. 1 pmol). After incubation for 15 minutes at room temperature a 2 mM p-mercaptoethanol (in ethanol) solution was added (1 pi) and the mixture was dried. The matrix, a-cyano-4-hydroxycinnamic acid (2 pi), was added to the micro tube and after 5 minutes 1 pi of this matrix was removed and applied to a target. 

This has been achieved by (a) reduction with 4 M mercaptoethanol (Thompson and O Donnell, 1961,1962b), (b) using 0.1 M benzyl mercaptan in ethanol-water mixture (Maclaren, 1962), (c) electrolytic reduction at a constant cathode potential, using catalytic concentrations of thioglycolate maintained in the SH form continuously (Leach et al., unpublished observations, 1963), and (d) repeated reduction and alkylation of the SH groups of the wool (O Donnell, 1954). 

Rockenberger et al. (1998) examined 1.8-nm nanocrystals of CdTe capped with mercaptoethanol molecules, and thus having surface CdS bonds. They found that the surface CdS local structure was distorted relative to the bulk CdTe, and attributed this to strain because of the differences in CdTe and CdS bonding. The coordination numbers derived from the EXAFS analysis were consistent with models of individual nanocrystals with discrete stoichiometries, e.g., Cd54Te32(S-ethanol)52 . 

Synonyms 2-ME Mercaptoethanol l-Ethanol-2-thiol 2-Hydroxy-1-ethanethiol 2-Hydroxyethyl mercaptan Monothioethyleneglycol 2-Thioetha-nol Thioglycol... 

The first group of sulphur compounds mentioned above can be defined as common fermentative sulphur volatiles (CFSV) and includes in our presentation ethylmercaptan (EtSH), dimethyl sulphide (DMS), diethyl sulphide (DES), dimethyl disulphide (DMDS), diethyl disulphide (DEDS), methyl thioacetate (MTA), ethyl thioacetate (ETA), 2-mercaptoethanol (ME), 2-(methylthio)-l-ethanol (MTE), 3-(methylthio)-l-propanol (MTP), 4-(methylthio)-l-butanol (MTB), benzothiazole (BT) and 5-(2-hydroxyethyl)-4-methylthiazole (HMT) (see Table 5.6). 

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