Sodium dodecyl sulfate 700 OXIDATIONS

Chromic acid oxidation of D-sorbitol and D-mannitol has been studied in the presence and absence of 2,2/-bipyridyl (bipy). A monomeric species of Cr(VI) has been found to be kinetically active in absence of bipy, whereas in the catalysed path the Cr(VI)-bipy complex has been found to be the active oxidant. Sodium dodecyl sulfate... 

Water [62], or water with addition of a polyethylene oxide-sodium dodecyl sulfate (PEO-SDS) complex [72], and formic acid [60,63,72] have been used to dissolve SEEP copolymers for fibre spinning. Water acts as a plasticizer in spun-fibres, inhibiting the 3-sheet conversion... 

Surface heterogeneity may be inferred from emission studies such as those studies by de Schrijver and co-workers on P and on R adsorbed on clay minerals [197,198]. In the case of adsorbed pyrene and its derivatives, there is considerable evidence for surface mobility (on clays, metal oxides, sulfides), as from the work of Thomas [199], de Mayo and co-workers [200], Singer [201] and Stahlberg et al. [202]. There has also been evidence for ground-state bimolecular association of adsorbed pyrene [66,203]. The sensitivity of pyrene to the polarity of its environment allows its use as a probe of surface polarity [204,205]. Pyrene or ofter emitters may be used as probes to study the structure of an adsorbate film, as in the case of Triton X-100 on silica [206], sodium dodecyl sulfate at the alumina surface [207] and hexadecyltrimethylammonium chloride adsorbed onto silver electrodes from water and dimethylformamide [208]. In all cases progressive structural changes were concluded to occur with increasing surfactant adsorption. 

Ethoxylated methylcarboxylates Propoxyethoxy glyceryl sulfonate Alkylpropoxyethoxy sulfate as surfactant, xanthan, and a copolymer of acrylamide and sodium 2-acrylamido-2-methylpropane sulfonate Carboxymethylated ethoxylated surfactants (CME) Polyethylene oxide (PEG) as a sacrificial adsorbate Polyethylene glycols, propoxylated/ethoxylated alkyl sulfates Mixtures of sulfonates and nonionic alcohols Combination of lignosulfonates and fatty amines Alkyl xylene sulfonates, polyethoxylated alkyl phenols, octaethylene glycol mono n-decyl ether, and tetradecyl trimethyl ammonium chloride Anionic sodium dodecyl sulfate (SDS), cationic tetradecyl trimethyl ammonium chloride (TTAC), nonionic pentadecylethoxylated nonylphenol (NP-15), and nonionic octaethylene glycol N-dodecyl ether Dimethylalkylamine oxides as cosurfactants and viscosifiers (N-Dodecyl)trimethylammonium bromide Petrochemical sulfonate and propane sulfonate of an ethoxylated alcohol or phenol Petrochemical sulfonate and a-olefin sulfonate... 

Note PEO = polyethylene oxide PVA = polyvinyl alcohol SDS = sodium dodecyl sulfate CTAB = cetyl trimethyl ammonium bromide. 

Guttman, A., Shieh, P, Lindahl, J., and Cooke, N., Capillary sodium dodecyl sulfate gel electrophoresis of proteins. II. On the Ferguson method of polyethylene oxide gels, /. Chromatogr., 676, 227, 1994. 

Benedek, K. and Thiede, S., High performance capillary electrophoresis of proteins using sodium dodecyl sulfate-poly(ethylene oxide), J. Chromatogr., 676, 209, 1994. 

The adsorption isotherm of sodium dodecyl sulfate (SDS) on alumina at pH = 6.5 in 0.1 M NaCI (Fig. 4.11a) is characteristic of anionic surfactant adsorption onto a positively charged oxide. As shown by Somasundaran and Fuerstenau (1966) and by Chandar et al. (1987), the isotherm can be divided into four regions. These authors give the following explanation for the adsorption mechanism ... 

Interaction of Long Chain Dimethylamine Oxide with Sodium Dodecyl Sulfate in Water... 

Long chain dimethylamlne oxides with alkyl chain length = 12, 14, 16, 18 carbons (Onyx Chem. Co., Jersey City, N.J.) and laboratory grade sodium dodecyl sulfate (Fisher Chem. Co., Fairlawn, N.J.) were used without further purification. 

The 1,3-dipolar cycloadditions of benzonitrile oxides with tertiary cinnamides yield the 5-phenyl and 4-phenyl regioisomers in a reversal of the expected regioselectiv-ities shown with methyl cinnamate. Calculations have shown that steric factors are responsible for this reversal of regioselectivity." The 1,3-dipolar cycloadditions of benzonitrile oxide with electron-rich and electron-poor dipolarophiles are accelerated by sodium dodecyl sulfate micelles. Phenyl nitrile ylides react with electron-deficient alkenes to produce five-membered -heterocycles where measured rate constants are between 4 x 10 and 7 x 10 lmoP ... 

In a previous publication ( ), results were presented on the micellar properties of binary mixtures of surfactant solutions consisting of alkyldimethylamine oxide (C12 to Cig alkyl chains) and sodium dodecyl sulfate. It was reported that upon mixing, striking alteration in physical properties was observed, most notably in the viscosity, surface tension, and bulk pH values. These changes were attributed to 1) formation of elongated structures, 2) protonation of amine oxide molecules, and 3) adsorption of hydronium ions on the mixed micelle surface. In addition, possible solubilisation of a less soluble 1 1 complex, form between the protonated amine oxide and the long chain sulfate was also considered. 

Octadecyldimethylamine oxide (CieDAO) was a commercial sample from Onyx Chemical Company, Jersey City, N. J. (25% active). After evaporating the solvent in a rotary evaporator under reduced pressure, the crude product was recrystallised several times from ethyl acetate. The final product was dried and stored in vacuo over P2O5. Sodium octadecyl sulfate (SODS) was a sample prepared in this laboratory previously, and was recrystallised from ethanol before use. Sodium dodecyl sulfate (SDS) was obtained from Aldrich Chemical Company, and was of 98% purity. It was further purified by repeated crystallisation from ethanol followed by ether extraction. Benzene and methanol were gold-label reagent grade, purchased from Aldrich Chemical Company (Metuchen, N. J.). 

Abbreviations ATP, adenosine-5 -triphosphate EPR, electron paramagnetic resL nance EXAFS, extended X-ray absorption 6ne structure Hb, hemoglobin Hb, oxidized (met-) hemoglobin NADH, reduced form of nicotinamide-adenosine dinucleotide PMS, phenazine methosulfate (methylsulfate salt of N-methylphenazonium cation) TMPD, N.N.N N -tetramethylphenylene-1,4 diaminium dication SDS-PAOE, sodium dodecyl sulfate-polyacrylamide gel electrophoresis. 

Bakshi, M. S., R. Crisantino, R. De Lisi, and S. Milioto. 1993. Volume and heat capacity of sodium dodecyl sulfate-dodecyldimethylamine oxide mixed micellAsPhys. Cherr07 6914-6919. 

Almgren. M., J. Van Stam, C. Lindblad, P. Stilbs, and P. Bahadur. 1991. Aggregation of polyethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymers in the presence of sodium dodecyl sulfate in aqueous solutiod.. Phys. Chem. 95 5677-5684. 

Azofluorene formation was decreased if the reacting mixture contained DNA. Two other products decreased by the presence of DNA was a band (Rf 0.31) II which turned brown-green within several hours of running the plate and a band (Rf 0.48) I which turned blue-green after running the plate. Ascorbate was needed to be added to the reaction mixture before extraction to observe band I. This suggests that I unlike II is fully oxidised in the reaction mixture. Oxidation of both products by H202 and peroxidase resulted in the rapid formation of the same transient blue intermediate as was observed with aminofluorene. Product I however bound much more rapidly to DNA than Product II and unlike Product II could not be removed from the DNA by extraction with 1% sodium dodecyl sulfate. Product II showed... 

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