Sodium laurylsulphate

Sodium dodecylsulphate (SDS, sodium laurylsulphate) [151-21-3] M 288.4, m 204-207°. Purified by Soxhlet extraction with pet ether for 24h, followed by dissolution in acetone MeOH H20 90 5 5(v/v) and recrystn [Politi et al. JPC 89 2345 1985], Also purified by two recrystns from absolute EtOH, aqueous 95% EtOH, MeOH, isopropanol or a 1 1 mixture of EtOH isopropanol to remove dodecanol, and dried under vacuum [Ramesh and Labes JACS 109 3228 1987. Also purified by foaming [see Cockbain and McMullen TFS 47 322 7957] or by liquid-liquid extraction [see Harrold J Colloid Sci 15 280 I960]. Dried over silica gel. For DNA work it should be dissolved in excess MeOH passed through an activated charcoal column and evaporated until it crystallises out. 

The adsorption of sodium laurylsulphate on PS latex was determined by using a differential refractometer (5). The sodium laury1-sulfate was a product of Eastman Kodak Company and did not undergo further purification. 

Foussereau J, Petitjean J, Lantz IP (1974) Allergy to sodium laurylsulphate. Contact Dermatitis Newslett 15 433... 

In the presence of nitrous oxide, the main high-energy species formed in pulse radiolysis of water is the hydroxyl radical. This reacts with sodium laurylsulphate by hydrogen-atom abstraction, which occurs at a range of possible sites in the alkyl chain. The resulting radical reacts with ferricyanide ion in an extramicellar environment, and their rate of decay permits values of = 1.5 X10 s and k" = 1.8 x 10 s to be derived (see pp. 190). By... 

The micellar residence time of Br was calculated to be 1.5 x 10 s . In like manner, pulse radiolysis of Ag2S04 in sodium laurylsulphate micelles gives Ag2, and the various decay processes may be analysed. Electron-transfer between quinone radical anions and quinones (the former generated from eaq reduction) may occur at the micelle surface in sodium laurylsulphate solution. The encounter rate constant for radical anion plus anionic micelle is an order of magnitude lower than for neutral molecule-micelle interactions because of charge-charge repulsions. " ... 

Quendiii of Exdted States.—Much research has been adapted from early observations that micelles could drastically alter the fluorescence lifetime of pyrene and the efficiency of excimer formation. The various mechanisms of excited-state transformation have been reviewed. " The polarity of the micellar surface may be estimated from the fluorescence spectrum of pyrene 2-carboxaldehyde " giving rise to the conclusion that sodium laurylsulphate (e=45) has a more polar surface than cetyltrimethylammonium bromide (e = 18). The fluidity of the site of solubilization may be estimated from fluorescence polarization " in surfactants of general structure (104). The Si... 

Results reported in Table I show that the presence of both a phosphonium salt and of a porous support like silica gel are important when 1-bromobutane is allowed to flow in the absence of a catalyst through ground potassium iodide, no 1-iodobutane is pratically obtained on the contrary, the conversion obtained in the presence of potassium iodide + silica gel clearly shows that the inorganic porous material plays the role of a solid solvent and actives iodide anion by interactions which diminish the bond strength of the K I ion pair. Furthermore catalytic amounts of the phosphonium salt lead to higher conversion while the presence of the anionic surfactant sodium laurylsulphate (NaLS) on the surface of silica gel does not yield different results from those obtained with silica gel alone. 

Sodium or TEA laurylsulphate (I), both of synthetic and coconut sources, is a micelle-forming, high-foaming surfactant that has a great scope of practical applications, particularly in detergents, cleaners, personal care products, synthetic fire-fighting foams, and industrial... 

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