Showing papers on "Acrylamide published in 1976"
TL;DR: The retention of low molecular weight proteins during electrophoresis through gradient polyacrylamid gels was improved when a gradient of N,N′,N″ -triallyl citric triamide (TACT) was superimposed on the gradient of acrylamide and N, N′ -methylenebisacryamide (MBA).
64 citations
TL;DR: Cereolysin was purified to apparent homogeneity by using ammonium sulfate fractionation, hydrophobic chromatography with AH-Sepharose, isoelectric focusing, and gel filtration, and discontinuous acrylamide electrophoresis to observe two forms of the toxin: oxidized and reduced.
Abstract: Cereolysin was purified to apparent homogeneity by using ammonium sulfate fractionation, hydrophobic chromatography with AH-Sepharose, isoelectric focusing, and gel filtration. The active form of the toxin had an isoelectric point of 6.6, and the molecular weight of the protein was about 55,500 as judged by sodium dodecyl sulfate-gel electrophoresis, gel filtration, and gel electrophoresis using various concentrations of acrylamide. Cereolysin contained two half-cystine residues and was dependent on reducing agents, such as dithiothreitol, for maximal hemolytic activity and charge homogeneity. By using discontinuous acrylamide electrophoresis, two forms of the toxin could be observed: oxidized and reduced. If the toxin was purified in the absence of dithiothreitol, partial spontaneous oxidation resulted in the formation of an oxidized form of the toxin. Relative to the reduced form, the oxidized form moved slightly closer to the anode in gel electrophoresis at pH 9.0. If the toxin was purified in the presence of 5 mM dithiothreitol or if the spontaneously oxidized toxin was preincubated with dithiothreitol, only the reduced form of the protein was observed. When the logarithims of their relative mobilities were plotted against the concentration of acrylamide in the gels, the slopes for the reduced and oxidized forms were identical. This indicates that the two forms are identical in size and are separable because of different charges. The reduced protein could be inhibited by N-ethylmaleimide, 5,59-dithiobis(2-nitrobenzoic acid), and p-hydroxymercuribenzoate. Inhibition by the latter two sulfhydryl reagents could be completely reversed by dithiothreitol. The reversibly oxidized form of the toxin did not appear to be inhibited by N-ethylmaleimide and apparently was either unable to bind to or had a decreased affinity for the erythrocyte membrane. Images
55 citations
TL;DR: A gas-liquid chromatographic method involving electron-capture detection has been developed for the determination of an acrylamide monomer present in trace amounts in water and no interferences were observed from sea water or from 8.0% of ammonium ions present as ammonium bromide.
Abstract: A gas-liquid chromatographic method involving electron-capture detection has been developed for the determination of an acrylamide monomer present in trace amounts in water. The method is based on bromination of the double bond by means of an ionic reaction and the 2,3-dibromopropionamide produced is extracted twice with 10 ml of ethyl acetate after salting out with sodium sulphate. The 2,3-dibromopropionamide from the reaction mixture is then cleaned up by using a Florisil column.The calibration graph for the method is linear over the range 0–50 pg of acrylamide monomer and the limit of detection is 0.032 µg l–1 for an aqueous standard solution. The yields of the brominated compound are 85.2 ± 3.3 and 83.3 ± 0.9% at fortification levels of 1.0 and 5.0 µg l–1, respectively. Recoveries of acrylamide monomer from river water, sewage effluent and sea water spiked at a level of 0.20 µg per 50 ml are 99.4 ± 2.5, 101.3 ± 3.0 and 98.0 ± 3.2%, respectively. No interferences were observed from sea water or from 8.0% of ammonium ions present as ammonium bromide.
41 citations
Patent•
12 Feb 1976
TL;DR: In this paper, the authors disclosed a hydrophilic gel suitable for exposure to repeated long-term contact with live tissues or mucous membranes and consisting of macromolecules obtained by polymerizing a mixture of at least two copolymerizable units and a crosslinking agent.
Abstract: There is disclosed a hydrophilic gel suitable for exposure to repeated long-term contact with live tissues or mucous membranes and consisting of macromolecules obtained by polymerizing a mixture of at least two copolymerizable units and a crosslinking agent. The mixture consists of from 52 to 99.5 parts by weight of N,N-diethylacrylamide, 43 to 0.1 parts by weight of a member selected from the group consisting of N,N-dialkyl acrylamide, N-alkyl methacrylamide, nitriles of acrylic and methacrylic acids and from 5 to 0.4 parts by of a divinylic monomer selected from the group consisting of diesters of acrylic acid and methacrylic acid, and methylene or ethylene-bis-methacrylamide or acrylamide.
37 citations
Patent•
17 Mar 1976TL;DR: In this article, an acrylamide-acrylic acid copolymer is formed by hydrolyzing a water-in-oil emulsion containing from 2-75% by weight of finely divided acryl-lamide polymer to the extent that between 0.8 and about 67% of the amide groups originally present in the polymer are converted into carboxyl groups.
Abstract: A process for recovering oil from subterranean oil-bearing formations which entails the use of a water treating medium. The water treating medium comprises an acrylamide-acrylic acid copolymer formed by hydrolyzing a water-in-oil emulsion containing from 2-75% by weight of finely divided acrylamide polymer to the extent that between 0.8 and about 67% of the amide groups originally present in the acrylamide polymer are converted into carboxyl groups.
34 citations
TL;DR: The susceptibility of the co-polymers to chymotrypsin attack decreases sharply with a decreasing spacing of the L-phenylalanine p-nitroanilide residue from the backbone of the polymer chains.
27 citations
TL;DR: No adverse effects were seen in the offspring, even at doses which produced neuropathy in the mothers, although this insensitivity is not due to failure of acrylamide to cross the placenta.
27 citations
TL;DR: Electrophoresis on acrylamide gels, inactivation rates at elevated temperatures and single dimensional electroimmunodiffusion found no evidence for the existence of an appreciable part of the enzyme in altered form.
22 citations
15 citations
Patent•
14 Jul 1976TL;DR: Polymeric surfactants are copolymers of acrylamide with 30 - 60 wt. percent of acrylic esters or alkyl or alkoxymethyl acrylides having molecular width from 800 to 10,000 amu as discussed by the authors.
Abstract: Polymeric surfactants are copolymers of acrylamide with 30 - 60 wt. percent of acrylic esters or alkyl or alkoxymethyl acrylamides having molecular wt. from 800 to 10,000 amu.
12 citations
Patent•
16 Jul 1976TL;DR: In this article, the pH of the dilute solution of the acrylamide polymer which is reacted is adjusted prior to addition of the aldehyde to between 45 and 55, thereby conducting this reaction at an acidic pH.
Abstract: Cationically modified polymers of acrylamide are prepared by adding to a polyacrylamide an aqueous solution of a lower aliphatic aldehyde followed by a lower alkyl secondary amine The pH of the dilute solution of the acrylamide polymer which is reacted is adjusted prior to addition of the aldehyde to between 45 and 55 thereby conducting this reaction at an acidic pH Additionally, quaternized polymers may be prepared by adding to the cationically modified polyacrylamide a lower alkyl halide quaternizing agent The pH of the solution of the cationically modified acrylamide polymer prior to quaternization should be 75-85
TL;DR: The present report describes the use of p -nitroanilide substrate- l -leucine- p -naphtylamide for detection of leucineaminopeptidase activity after acrylamide gel electrophoresis, which allows a rapid and sensitive localization of leukineaminopesptidases.
Patent•
14 May 1976TL;DR: In this article, a porous acrylamide polymer without loss of solubility in water is prepared by boiling the water within the polymerization system with the heat of polymerization. But this method requires a large amount of water.
Abstract: PURPOSE: To prepare a porous acrylamide polymer without loss of solubility in water by boiling the water within the polymerization system with the heat of polymerization. COPYRIGHT: (C)1977,JPO&Japio
Patent•
08 Nov 1976TL;DR: In this paper, poor quality acrylamide can be used to produce good quality water-soluble polymers by conducting the polymerization in the presence of urea, which can be applied to produce water solubility polymers.
Abstract: Poor quality acrylamide can be used to produce good quality water-soluble polymers by conducting the polymerization in the presence of urea
Patent•
22 Mar 1976
TL;DR: In this paper, the anionic, cationic or nonionic acrylamide polymer is treated by adding 0.5-30 (1-15) wt.% (w.r.t.) of citric-, ricinoleic lactic- and/or methylene-5,5'-disalicylic acid.
Abstract: Parent Patent discloses prepn. of solid, flowable acrylamide polymers which do not agglomerate when dissolved in water. In this Patent of Addition, the anionic, cationic or nonionic acrylamide polymer is treated by adding 0.5-30 (1-15) wt.% (w.r.t. polymer) of citric-, ricinoleic lactic- and/or methylene-5,5'-disalicylic acid, or their ammonium- or alkali salts, esters or amides. Acrylamide polymers are used as sizes, fillerS, binders retention agents, paints, dispersants and flocculants. Acrylamide polymers contg. >60 (>90)% polyacrylamide can be dissolved directly without lump-formation.
Patent•
20 Oct 1976
TL;DR: In this article, the authors proposed a method to remove unreacted residual monomers from hydrous acrylamide polymers with efficiency in a short time, by controlling the moisture content of the polymers and the amount of organic solvent to be used.
Abstract: PURPOSE: To remove unreacted residual monomers from hydrous acrylamide polymers with efficiency in a short time, by controlling the moisture content of the polymers and the amount of organic solvent to be used. COPYRIGHT: (C)1978,JPO&Japio
Patent•
05 Mar 1976
TL;DR: In this article, the preparation of acrylamide by treating acrylonitrile with specific strong acidic cation exchange resin, followed by reacting with water was described, where the acidity of the resin was controlled by water.
Abstract: PURPOSE: Economical preparation of acrylamide by treating acrylonitrile with specific strong acidic cation exchange resin, followed by reacting with water. COPYRIGHT: (C)1977,JPO&Japio
Patent•
14 Jan 1976TL;DR: In this paper, high molecular weight water-soluble acrylamide polymers can be produced in good yield by irradiating a solution comprising acetone, water and acarlamide with an ionizing radiation in the presence of an alkaline salt.
Abstract: High molecular weight water-soluble acrylamide polymers can be produced in good yield by irradiating a solution comprising acetone, water and acrylamide with an ionizing radiation in the presence of an alkaline salt.
TL;DR: Columns containing immobilized immunoglogulin G fractions from normal and immunized animals were used to purify the wild-type beta component of Escherichia coli tryptophan synthase, formula alpha2 beta2, and a mutant form of the beta component, yielding proteins with no detectable contaminants.
Abstract: Columns containing immobilized immunoglobulin G fractions from normal and immunized animals were used to purify the wild-type β component of Escherichia coli tryptophan synthase, formula α2β2, and a mutant form of the β component. The procedure yielded proteins with no detectable contaminants as measured by analytical acrylamide disc gel electrophoresis and immunodiffusion against proteins subject to sodium dodecylsulfate acrylamide electrophoresis. After elution from the antibody column at pH 11 the normal β component, by dialysis against pyridoxal phosphate at pH 7.5, could be restored to the enzymatically-active β2 dimer with a specific activity of 1700 enzyme units/mg protein. This compares with reported values of 2500—3000 enzyme units/mg when the β2 dimer is purified by conventional means.
TL;DR: Molecular weight and N-terminal amino acid analyses of the proteins of egg yolk phosvitin were made using SDS acrylamide disc gel and phenylisothiocyanate techniques, respectively.
Patent•
09 Jan 1976
TL;DR: In this article, the authors describe the preparation of acrylamide polymers having such an improved tackiness as to be pulverizable, which is the case of polycyclic polymers.
Abstract: PURPOSE: Preparation of acrylamide polymers having such an improved tackiness as to be pulverizable. COPYRIGHT: (C)1977,JPO&Japio
Patent•
30 Sep 1976
TL;DR: In this article, a copper catalyst has been used for the hydrolysis of acrylonitrile in the presence of water and an organic solvent, at a temperature in the range of from about 1000° to about 1500° C.
Abstract: Acrylamide may be prepared by the hydrolysis of acrylonitrile by treating the acrylonitrile with water in the presence of a copper catalyst which has been prepared by volatilizing copper metal at a temperature in the range of from about 1000° to about 1500° C. in vacuo and condensing the vapors in the presence of an organic solvent.
Patent•
13 Dec 1976
TL;DR: In this article, a method for degrading residual scrylamide monomer in its polymer, by the use of bacteria, was proposed, which was shown to work well in the presence of bacteria.
Abstract: PURPOSE:A method for degrading residual scrylamide monomer in its polymer, by the use of bacteria.
Patent•
17 Feb 1976
TL;DR: In this paper, a method of purification of acrylamide aqueous solution comprises distilling off unreacted acrylonitrile in the acrylamide solution in the absence of oxygen, treating the resultant solution while keeping the concentration of dissolved oxygen 4 ppm or higher.
Abstract: PURPOSE: A method of purification of acrylamide aqueous solution comprises distilling off unreacted acrylonitrile in the acrylamide solution in the absence of oxygen, treating the resultant solution while keeping the concentration of dissolved oxygen 4 ppm or higher, and finally treating it with ion exchange resins COPYRIGHT: (C)1977,JPO&Japio
Patent•
14 Oct 1976
TL;DR: In this article, a process for preparing sedimentation stable acrylamide polymer (I) water in oil dispersions by polymerising a water in an oil emulsion of an aq. soln.
Abstract: A process for preparing sedimentation stable acrylamide polymer (I) water in oil dispersions by polymerising a water in oil emulsion of an aq. acrylamide soln. opt. contg. =50 wt. % of other water soluble monomers in a hydrophobic organic dispersion medium (II) in the presence of an emulsifier and an initiator is characterised in that (II) is a mixt. of a liquid hydrocarbon and a chloroparaffin having a density deviating is not >0.2 kg/m3 from that of the dispersed aq. phase. The dispersion is sedimentation stable and may be used as a flocculant, in the paper industry, in the treatment of industrial waste water, as a dispersion aid and protective colloid for boring mud and as in aid in secondary oil transportation.
Patent•
11 Dec 1976
TL;DR: In this paper, a gel-free acrylamide (AAM) polymer is obtained by drying the hydrous polymer prepd. in an aq. medium in the presence of a specific antigeling agent.
Abstract: PURPOSE:Powers of a gel-free acrylamide (AAM) polymer are obtained by drying the hydrous polymer prepd. by polymn. in an aq. medium in the presence of a specific antigelling agent.
Patent•
14 Jun 1976TL;DR: In this paper, the authors showed that the solubility of acrylonitrile in the aqueous feed solution is increased by acrylamide cosolvent in the feed solution.
Abstract: In the catalytic hydration of acrylonitrile to produce acrylamide by contacting aqueous solution of acrylonitrile with a catalyst, the solubility of acrylonitrile in the aqueous feed solution is increased by presence of acrylamide cosolvent in the feed solution, enabling feed solutions having concentration of acrylonitrile higher than the saturation concentration of acrylonitrile in water without a cosolvent.
Journal Article•
TL;DR: Cells of Bacillus megaterium immobilized due to incorporation into polyacrylamide gel retained their viability but differed significantly in their enzymic activity from free cells: 20alpha- and 20beta-hydroxysteroid dehydrogenase activites were substantially decreased and they showed the capacity to synthesize significant quantities of a new derivative and to destruct steroids.
Abstract: Cells of Bacillus megaterium immobilized due to incorporation into polyacrylamide gel retained their viability. They differed significantly in their enzymic activity from free cells: 20alpha- and 20beta-hydroxysteroid dehydrogenase activites were substantially decreased and they also showed the capacity to synthesize significant quantities of a new derivative and to destruct steroids. Immobolized protein fractions maintained 20alpha-hydroxysteroid dehydrogenase and 20beta-hydroxysteroid dehydrogenase activities but their specific activites were lower than those of native protein fractions. It is suggested that the synthesis of new compounds was induced by acrylamide that was bound during polymerization.
Journal Article•
TL;DR: In this paper, the authors investigated the graft copolymerization of acrylamide and acrylonitirile to silk fibroins and found that the degree of grafting was increased generally with increase in the reaction time and reaction temperature.
Abstract: Cerium (Ⅳ) ion-initiated graft copolymerizations of acrylamide and of acrylonitirile to silk fibroins were investigated. When acrylamide was used, the change in ceric ammonium nitrate concentration exhibited a maximum in degree of grafting at 0.01 M. Also observed was that the change in acetic acid content in reaction media gave a maximum in degree of grafting at 7% acetic acid in water. Degree of grafting was increased generally with increase in acrylamide concentration reaction time and reaction temperature. When acrylonitrile monomer was used for grafting,different results were obtained. Addition of nitric acid was more effective in enhancing the degree of grafting than the addition of acetic acid.Generally the grafting of acrylonitrile to silk fibroins was less efficient than the grafting of acrylamide. The portion of grafted silk fibroins insoluble in Lowe's reagent exhibited the IR absorption bands characteristics to both vinyl polymers and silk fibroins, indicating the grafting of vinyl monomers to silk fibroins. To examine the molecular weight of graft vinyl polymer, a sample of grafted silk was hydrolyzed by 10% sodium hydroxide. Viscosity measurements indicated that the molecular weight of the graft polymer was in the range of 105