Pyrophosphates acid buffer

The 50% inhibition concentration of erbstatin against tyrosine kinase was 0.55 p,g/ml, when it was examined as follows The reaction mixture contained 1 mM MnCl2, 100 ng EGF, 40 lg protein of A431 membrane fraction, 75 lg of albumin, 3 lg of histone, and HEPES (N-2-hydroxyethylpiperazine-N -2-ethanesulfonic acid) buffer (20 mM, pH 7.4) in a final volume of 50 (11. The reaction tubes were placed on ice and incubated for 10 minutes in the presence or absence of erbstatin. The reaction was initiated by the addition of labeled ATP (10 (11), and the incubation was continued for 30 minutes at 0°C. Then aliquots of 50 (11 were pipetted onto Whatman 3MM filter paper and put immediately into a beaker of cold 10% TCA containing 0.01 M sodium pyrophosphate. The filter papers were washed extensively with TCA solution containing 0.01 M sodium pyrophosphate at room temperature, extracted with ethanol and ether, and then dried. Radioactivity was measured by a scintillation counter. 

Tetrapotassium pyrophosphate Tetrasodium pyrophosphate Triethanolamine Triisopropanolamine Tris (hydroxymethyl) aminomethane Uric acid buffer, dentals Tetrasodium pyrophosphate buffer, detergents Potassium bicarbonate buffer, diagnostics Aminomethyl propanol buffer, drilling muds... 

Succinic acid L-Tartaric acid Tetrasodium pyrophosphate Triethanolamine Tris (hydroxymethyl) aminomethane buffer, processed food Sodium phosphate tribasic dodecahydrate buffer, solutions Sodium citrate buffer, supplements Sodium citrate buffer, tablets Sodium citrate buffer, textile baths Acetic acid buffer, textile dyeing Citric acid... 

Tetrasodium pyrophosphate is used as a pH buffer (a substance that maintains a particular acidity level), and as a dough conditioner in soy-based meat alternatives. It promotes binding of proteins to water, binding the soy particles together, and is used for the same purpose in chicken nuggets and imitation crab and lobster products. 

In acidic solution MnOj is usually the end product, although particularly vigorous reductants, e.g. iodide and oxalate ions, convert permanganate to manganous ions. Mn(III) is stable only in acidic solution or in the form of a complex, e.g. with pyrophosphate ion, and it has seldom been reported as the end product of a permanganate oxidation, e.g. for that of Mn(II) in a phosphate buffer and for those of alcohols and ethers in the presence of fluoride ion. ... 

The reactivity of acidified chlorite solutions is reduced for bleaching some textiles by adding compounds like polyamines, pyrophosphates, and hydrogen peroxide that suppress the formation of chlorine dioxide (57). Another method is to buffer the solution at pH 5—6 to reduce the rate of chlorine dioxide formation. Hydrolysis of anhydrides and esters or oxidation of alcohols can be used to slowly generate acids to promote chlorine dioxide formation (58). Aldehydes also promote chlorine dioxide generation from neutral chlorite solutions, but the effect is greater than simply lowering the pH as they... 

Phosphate Buffer Transfer 50.0 g of potassium pyrophosphate into a 500-mL volumetric flask, and dissolve in 400 mL of water. Adjust, if necessary, to a pH of 9.0 with 1 N hydrochloric acid, dilute to volume with water, and mix. 

The reaction mixture contained in 1.0 mL 20 /tinol of D-Val, 10 nmol of FAD, 10 fig of catalase, and 2 nmol of ketovaleric acid in 0.1 Af pyrophosphate buffer (pH 8.5). The enzymatic reaction was started by adding 10 to 100 fiL of beef kidney homogenate. At different times, 200 fiL aliquots were withdrawn and added to 100 fiL of ice-cold 6 Af HC1. After centrifugation, a... 

Sources of enzyme were partially purified type II D-amino acid oxidase from porcine kidney, and the supernate from a beef kidney homogenate prepared in 2.5 volumes of 0.1 M pyrophosphate buffer (pH 8.5) containing 10 fiM FAD. The supernate obtained by centrifugation was used. 

The reaction mixture contained 80 /xL of 130 mM Hepes-67 mM Tris buffer (pH 7.4) 10 ju,L each (to give final concentration of 1 mM) of NAD, thiamine pyrophosphate, coenzyme A, MgCl2, and dithiothreitol 20 /xL of tissue extract or enzyme source, and 30 /xL of bovine serum albumin (1 mg). The reaction was started by adding 20 fiL of a-ketoglutarate to give a final concentration of 10 mM After incubation at 30°C for 1, 5, or 20 minutes for purified enzyme from bovine heart, brain, or liver mitochondria, or platelet homogenates, the reaction was stopped by addition of 20 /xL of 60% perchloric acid and the denatured protein was removed by centrifugation. A 10 /xL aliquot was used for HPLC analysis. 

Characteristics of the Enzyme. S-alkyl-L-cysteine sulfoxide lyases prepared from garlic 17, 19) and onion 24, 25, 39) are similar. They differ primarily in their response to pH—the garlic enzyme has a broad pH optimum from 5 to 8 and may be precipitated at pH 4.0 and redissolved without loss of activity (17) while the onion enzyme is sensitive to acid and is most active at pH 8.8 in pyrophosphate buffer 24, 39). The purified garlic enzyme showed a sharper pH optimum at pH 6.5 40). The Brassica enzyme is most active at pH 8.5 in borate buffer (27) and remains soluble and active when other proteins are precipitated at pH 4.0. 

It has been reported that a yellow substance is liberated from crystalline, sweet-potato beta-amylase when the enzyme is subjected to gel filtration on Sephadex at pH 8.8 in the presence of pyrophosphate buffer. The chromophoric material can also be obtained by treating the enzyme with acetic acid, and can readily be reattached. 

The hydrolysis of inorganic pyrophosphate has been carried out in cacodylate buffer, pH 5.5 [179], trichloroacetic acid was then added to terminate the reaction, denatured protein was sedimented by centrifugation, and suitable aliquots of the supernatant solution were assayed for inorganic phosphate by the method of Fiske and SubbaRow [163]. 

In studies carried out in the pH range of 3 to 6, it was necessary to buflFer the solutions, since Reaction 8 tends to increase the acidity. Only phosphate and pyrophosphate buffers were used almost all other buffer systems would be attacked by the OH or HO2 radical. (Fluoride buffers could probably be used, although there are difficulties associated with the measurement of pH.) In addition, early exploratory experiments, not reported in detail here, indicated that spurious results would be obtained in buffers containing unpurified alkali. In these experiments the rate of reaction was much more rapid than in pyrophosphate buffers which did not contain alkali, and somewhat lower values of R were observed. 

Phosphatidylinositol turnover was assayed by incorporation of labeled inositol into phospholipids. A431 cells were preincubated in HEPES-buffered saline containing [ H]inositol at 37°C for 30 min. Then, test chemical and EGF were added, and the incubation was continued for 60 min. Subsequently, 10% trichloroacetic acid containing 0.01 M sodium pyrophosphate was added, and the acid-insoluble fraction was scraped off from the dish in H2O. The lipid was extracted from it by the addition of CHCI3 and CH3OH (1 1), and [3r]inositol-labeled lipids were counted by liquid scintillation spectrophotometry. 

The sample preparation of dental care products depends on the kind of formulation. Organic components such as emulsifiers, surfactants and thickeners have to be removed as well as the water-insoluble abrasives. In the case of very low fluoride and phosphate content, it is recommended to evaporate the aqueous extract. The chemical shift of the phosphate signals depends considerably on the pH of the solution, therefore a buffer of pH of 8-9 should be used. With strong acidic or basic medium, hydrolysis of meta- and pyrophosphate occurs. The ring opening of the metaphosphate producing the linear triphosphate is easily detected in the P NMR spectrum (Figure 3-48). 

Ammonium citrate dibasic Ammonium formate Ammonium phosphate Betaine hydrochloride Diethylamine Dipropylenetriamine N-Hydroxysuccinic acid isopropanoiamine Lithium hydroxide N-Methylethanoiamine Sodium acid pyrophosphate Sodium metasilicate Sodium metasiiicate pentahydrate Sodium phosphate dibasic anhydrous Sodium phosphate dibasic dihydrate Trisodium citrate buffer component... 

Sodium tartrate Succinic acid Succinic anhydride Tetrasodium pyrophosphate Trisodium citrate buffer, gel electrophoresis Tris-borate-EDTA buffer, high pressure equip. 

The formation of fiirfiiryl mercaptan in model systems was recently investigated by Grosch and Zeiler-Hilgart. The model systems included various combinations of cysteine, ribose, thiamine, hydrogen sulfide, reduced glutathione, and 5 -inosinic acid in pH 5.7 pyrophosphate buffer. They found that the level of Fur-SH generated in aqueous model systems at boiling temperatures was always low (9). 

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