Salt washing

Arsonic acids, like carboxylic and sulphonic acids (pp. 349, 353), usually give crystalline benzylthiouronium salts. Add just sufficient dilute aqueous sodium hydroxide dropwise with shaking to a suspension of 0 5 g. of phenylarsonic acid in 10 ml. of water to give a clear solution. Then add 0 5 g. of benzylthiouronium chloride dissolved in 10 ml. of water. Filter off the precipitated benzylthiouronium salt, wash with water and dry m.p. 114-117° it tends to dissociate on attempted recrystallisation. 

Anilides. Dilute the acid chloride with 5 ml. of pure ether (or benzene), and add a solution of 2 g. of pure aniline in 15-20 ml. of the same solvent until the odour of the acid chloride has disappeared excess of aniline is not harmful. Shake with excess of dilute hydrochloric acid to remove aniline and its salts, wash the ethereal (or benzene) layer with 3-5 ml. of water, and evaporate the solvent [CAUTION ] Recrystallise the anilide from water, dilute alcohol or benzene - light petroleum (b.p. 60-80°). 

Benzenesulfinic acid [618-41-7] M 142.2, m 84 , pK 2.16 (2.74). The acid is purified by dissolving the Na salt in H2O, acidifying to Congo Red paper with HCl and adding a concentrated soln of FeCl3 whereby Fe sulfinate ppts. Collect the salt, wash with a little H2O, drain, suspend in H2O and add a slight excess of 1.5M aq NaOH. The Fe(OH)3ppts, it is filtd off, the sulfinic acid in the aq soln is extracted with... 

High-salt wash solution 2X SSC, 0.1% sodium dodecyl sulfate (SDS). 

The temperature of the hybridization oven is reduced to 25-30°C. The wash solution is replaced by low-salt wash solution 2 to approx. 80% capacity of the container and rotated for 5 min. 

The microarray is removed from the hybridization box using forceps and immediately transferred to the beaker of room temperature low-salt wash solution 2. The microarray is dipped several times into the wash solution. 

In a 5-I. round-bottom flask fitted with a stopper holding a reflux condenser and a separatory funnel, are placed 294 g. (6 moles) of sodium cyanide and 300 cc. of water. The flask is heated on a steam bath until most of the sodium cyanide is in solution. This requires two to three hours. A solution of 500 g. (2.47 moles) of trimethylene bromide (Note 1) in 11. of 95 per cent alcohol is then added through the separatory funnel over a period of forty to sixty minutes. The mixture is refluxed for thirty to forty hours (Note 2) on a steam bath. Then the solvent is removed, preferably under reduced pressure. The residue, consisting of sodium bromide, sodium cyanide, and trimethylene cyanide, is extracted with 300-400 cc. of ethyl acetate, which dissolves the trimethylene cyanide and does not dissolve the inorganic salts. This solution is filtered and the salt washed once with about 100 cc. of ethyl acetate. The ethyl acetate is distilled at ordinary pressure (Note 3) and the residual liquid is distilled under reduced pressure. The yield of trimethylene cyanide boiling at i44-i47°/i3 mm. or i3i-i34°/io mm. is 180-200 g. (77-86 per cent of the theoretical amount). 

About lOOg of pyridine rhodanilate is obtained. To convert this into the ammonium salt for re-use, suspend it in 175 ml of methanol and add 90 ml of concentrated ammonia solution. Stir at 0 °C for 30 minutes and then dilute gradually with 900 ml of water. Filter off the precipitated ammonium salt, wash it with water and repeat the... 

Downstream processing may consist of several operations such as liming to precipitate the metabolite as the calcium salt, washing of the precipitate with water to remove soluble impurities, acidification using strong acids to convert the salt in its free acid form. The acidic liquor may be demineralized using IER, decolorized using active carbons, concentrated under vacuum, and finally crystallized. 

High-salt wash buffer 0.1 Af Tris-HCl pH 8.0,0.5 Af NaCl. 

Resuspend each pellet in 2 mL of ice-cold high-salt wash buffer by pipetting up and down several times. Once the pellet is resuspended, adjust solution volume to 30 mL in each tube, using the same ice-cold buffer. 

Ghanotakis, D.F., Yocum, C.F. and Babcock, G.T. 1986. ESR spectroscopy demonstrates that cytochrome b-559 remains low potential in Ca2+-reactivated, salt-washed PS II particles. Photosynthesis Research, 9,125-134. Hervas, M., Ortega, J.M., de la Rosa, M.A., de la Rosa, F.F. and Losada, M. 1985. Location and function of cytochrome b-559 in the chloroplast non-cyclic electron transport chain. Physiol. Veg., 23,593-604. 

Now cover the mercury with dried and powdered sea salt. Mix these two completely using a mortar and pestle. Depending on the impurities in the mercury, the salt may darken even to blackness. Wash this dirty salt out using rainwater and repeat the salt washing once or twice. The mercury will retain some of the subtle essence of the salt which is important for the rest of the processes. 

C. Methyl a-(bromomethyl)acrylate. in a dry, 250-mL three-necked flask, equipped with a mechanical stirrer, reflux condenser, and an addition funnel, 20 g (0.077 mol) of methyl 3, 3 -dibromoisobutyrate (Note 14s 6) in 50 mL of anhydrous benzene (Note 157) is stirred vigorously. Triethylamine (Notes 168 and 17) (7.7 g, 0.076 mol) in 50 mL of benzene is introduced dropwise at a rate of about 3 mL. per min. After the addition is complete the mixture is stirred for an additional 1 hr at room temperature, refluxed for 1 hr, and then cooled to 20°C. The reaction mixture is filtered with suction and the amine salt washed twice with 20 mL of benzene. The filtrate and washings are combined in a round-... 

Filter off the precipitated phosphonium salt, washing well with diethyl ether (30 mL). 

The reaction mixture is cooled, filtered, and the salt washed with a little chloroform and sucked dry The yield should be 90 per cent of the theory. The salt darkens above i8io° and melts at 1920... 

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