Decyl sulfate

Sanchez et al. [61,62] studied the stability of sodium decyl, dodecyl, and tetradecyl sulfates and sodium lauryl ether (3 EO) sulfate in acid media (pH 1) at different temperatures and concentrations above and below the critical micelle concentration. Sodium decyl sulfate was shown to be relatively stable for several hours at temperatures up to 90°C. Sodium dodecyl and tetradecyl sulfates were only stable for short periods of time at temperatures above 40-50°C. As expected, sodium lauryl ether sulfate was less stable to hydrolysis than the corresponding lauryl sulfate. 

The influence of the presence of alcohols on the CMC is also well known. In 1943 Miles and Shedlovsky [117] studied the effect of dodecanol on the surface tension of solutions of sodium dodecyl sulfate detecting a significant decrease of the surface tension and a displacement of the CMC toward lower surfactant concentrations. Schwuger studied the influence of different alcohols, such as hexanol, octanol, and decanol, on the surface tension of sodium hexa-decyl sulfate [118]. The effect of dodecyl alcohol on the surface tension, CMC, and adsorption behavior of sodium dodecyl sulfate was studied in detail by Batina et al. [119]. 

Shedlovsky et al. studied mixtures of sodium decyl, dodecyl, and tetradecyl sulfates by electromotive force measurements and determined the extent of the dissociation of the sodium counterions by the micelles. From the data obtained strong interaction below the CMC was found for all of the mixtures except those containing more than 25 mol % of sodium decyl sulfate [122]. Commercial alcohol sulfates are mixtures of homologs with different hydrocarbon chains. It has been demonstrated [123] that the CMC of such products is lower than that expected by calculation from the linear relationship between log CMC and the number of carbon atoms of the alcohol as stated in Eq. (11). These results are shown in Fig. 9. 

Abbreviations. aT = a-tocopherol, AC = aminocoumarin, ANS = l-anilino-8-naphthalenesulfonic acid, CTAB = cetyltrimethylammonium bromide, DPPC = dipalmitoylphosphatidylcholine, DPPH — l,l-diphenyl-2-picrylhydrazyl, DSHA = Ai-dansylhexadecylamine, GMO = glycerol monooleate, HC = hydrocoumarin, N,N -DOC = JV,JV -di(octadecyl)oxacarbocyanine, PC = phosphatidylcholine, p-CUO = pyrene caroboxaldehyde, SDES — sodium decyl sulfate, SDS — sodium dodecyl sulfate, STS = sodium tetradecyl sulfate. 

Murthy and Ryan [823] used colloid flotation as a means of preconcentration prior to neutron activation analysis for arsenic, molybdenum, uranium, and vanadium. Hydrous iron (III) oxide is floated in the presence of sodium decyl sulfate with small nitrogen bubbles from 1 litre of seawater at pH 5.7. Recoveries of arsenic, molybdenum, and vanadium were better than 95%, whilst that of uranium was about 75%. 

An especially effective reduction of the Krafft Point results from the insertion of ether groups into the molecule of the anionic surfactant. In table I this is examplified with Na dodecyl sulfate and Na-tetra-decyl sulfate in comparison to various n-alkyl ether sulfates of the same chain length (10). As a measure of the Krafft Point, a temperature is deTined at which a 1 7o solution dissolves clearly. By the incorporation of oxyalkylene groups into the molecule, the Krafft -Point and the melting point are greatly depressed. This depression is especially effective if there is branching in the oxyalkylene groups. 

The most commonly used procedure for checking the purity of proteins is sodium do-decyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). In electrophoresis, molecules move in an electrical field (see p.276). Normally, the speed of their movement depends on three factors—their size, their shape, and their electrical charge. 

Since the early delipidation procedure was applied initially to the whole serum (815) and later to the isolated serum lipoproteins (818), many other methods of delipidation have been reported [see reference (816) for review], employing mixtures of organic solvents (ethanol-ethyl ether chloroform-methanol, acetone, etc.) or detergents (sodium dodecyl or decyl sulfate, Triton X-100, Nonidet, etc.). Techniques for delipidation have not been standardized, nor is there a comprehensive comparative assessment of the various proposed methods presently avail-... 

The retention of polar amino acids can be enhanced by the inclusion of decyl sulfate (203) or other anionic surfactants (234) in the eluent. The use of such agents in the mobile phase modifies stationary phase interactions... 

Measurements have been carried out on the excess tensions, equilibrium thicknesses, and compositions of aqueous foam films stabilized by either n-decyl methyl sulfoxide or n-decyl trimethyl ammonium-decyl sulfate, and containing inorganic electrolytes. 

Liu YC, Baglioni P, Teixeira J, Chen SH (1994) Structure and Interaction of lithium do-decyl sulfate micelles in the presence of Li-specific macrocyclic cage a study by SANS. J Phys Chem 98(40) 10208-10215... 

Figure 2. Effect of pH on ii-A and Av-A isotherms of sodium octa-decyl sulfate (SODS) at 25 C, O.OIM NaCl subsolutions (NaOH or HCl/NaCl). Substrate pH 1-10.9, 2-5.5, 3-2.2.

The monoalkyl derivatives in salt form appear to have low toxicity. The monomethyl sulfate sodium salt has an approximate oral lethal dose greater than 5000 mg/kg of body weight for rats (129). Mono do decyl sulfate sodium salt is widely marketed as a deteigent and shampoo ingredient (oral LD ( 1268 mg/kg for rats) (126). Both dimethyl sulfate and monomethyl sulfate occur in the environment in coal fly-ash and in airborne particulate matter (130). 

Rogers and Schulman (45) report the existence of both a specific cation and a specific anion effect on ir-A isotherms for the anionic octa-decyl sulfates. The anionic fatty acids have indicated a specific cation effect, but no demonstration of an anion effect has been attempted. However, the long-chain cationic surfactants STA+ exhibit a specific anion effect only. 

Burnette, W.N. 1981. Western blotting Electrophoretic transfer of proteins from sodium do-decyl sulfate-polyacrylamide gels to unmodified nitrocellulose and radiographic detection with antibody and radioiodinated protein A. Anal. Biochem. 112 195-203. 

A micelle is a dynamic structure. Surfactants leave the micelle and go into solution while other surfactants enter the micelle from solution. The timescales involved depend critically on the specific structure of the surfactant, in particular on the length of the hydrocarbon chain. For example, the residence time of a single dodecylsulfate (CH3(CH2)h0S03 ) in a SDS micelle at 25° C is 6 /xs [525], If we reduce the chain length by two methylene units to decyl sulfate (CH3(CH2)g0S03 ) the residence time decreases to roughly 0.5 /us. Tetradecyl sulfate (CH3(CH2)i30S03 ), which has two methylene units more than dodecylsulfate, typically remains 83 /its in a micelle. 

Satake, I. and Yang, J.T. (1976) Interaction of sodium decyl sulfate with poly(L-omithine) and poly(L-lysine) in aqueous solution. Biopolymers, 15, 2263-2275. 

Sodium decyl sulfate Sodium dodecyl sulfate (SDS)... 

The isolation of bacterial DNA described in this experiment, patterned after the work of Marmur (1961), accomplishes these objectives. Bacterial cells are disrupted by initial treatment with the enzyme, egg-white lysozyme, which hydrolyzes the peptidoglycan that makes up the structural skeleton of the bacterial cell wall. The resultant cell walls are unable to withstand osmotic shock. Thus, the bacteria lyse in the hypotonic environment. The detergent, sodium dodecyl sulfate, (SDS, sodium do-decyl sulfate) then completes lysis by disrupting residual bacterial membranes. SDS also reduces harmful enzymatic activities (nucleases) by its ability to denature proteins. The chelating agents, citrate and EDTA (ethylenediamine tetraacetic acid), also inhibit nucleases by removing divalent cations required for nuclease activity. 

Inhibition by l-decanol > 1-heptanoI > 1-butanol > ethanol Sodium 2-hexadecyl sulfate kijilko = 79-2 Sodium hexadecyloxy-ethyl sulfate kifilkt = 30-6 Disodium 2-sulfoocta-decyl sulfate k jko = 139 Sodium methyl-2-sulfohexadecanoate ... 

Sodium octyl sulfate -I- H3O+ Sodium decyl sulfate + OH Sodium decyl sulfate -t- H2O... 

Sodium decyl sulfate, non-ionic surfactants such as polyoxyethyl-ene(20) sorbitan monooleate, and the polymer polyvinylpyrrolidone have been shown to enhance the photobleaching of riboflavin (Kostenbauder and DeLuca, 1963 Kostenbauder et al., 1965). The effects of surfactants and other macromolecules on the rate constants for the photobleaching of riboflavin and acetylriboflavin together with the relative fluorescent... 

Effect of Sodivim Decyl Sulfate on the Photobleaching of Riboflavin in Oxygen Saturated Solutions - <>... 

From studies of Langmuir films (insoluble surfactants) and films adsorbed to solid substrates, alkyl chains are known to be well ordered. For soluble surfactants at oU/water, however, the picture is much different. Several studies from this laboratory have demonstrated these differences [6,37-39]. Figure 2.6 shows the ssp spectra for sodium do-decyl sulfate (SDS) at the CCI4/D2O interface at monolayer coverage (squares) and at extremely low surface coverage (circles) with the spectra normalized to the methyl symmetric stretch [6]. 

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