Lauryl sulfate anion

Sodium lauryl sulfate (anionic surfactant) Stepan Bio Soft D-62 (LAS-anionic surfactant Triethanolamine (TEA)... 

Small LL interfaces have been used by Girault and co-workers (33-38) and by Senda et al. (39, 40). We have used a small hole formed in a thin glass wall (41-43). Figure 16 shows the voltammetric response of lauryl sulfate anion transport between water and nitrobenzene. Recent analytical applications of these microinterfaces have resulted in construction of gel-solidified probes. The advantage of such a modification is ease of handling (44-47). The immobilization can be extended further to studies of frozen interfaces, or even to solid electrolytes. Significantly, ITIES theory also applies to interfaces that are encountered in ion-doped, conductive, polymer-coated electrodes. 

Mono-, di-, triethanolamine lauryl sulfate Anionic Manindale... 

Sodium Lauryl Sulfate Anionic Surfactant, emulsif5dng agent, lubricant 1-2% 36-51... 

Notice that the lauryl sulfate anion has a long, nonpolar tail and a highly polar (negatively charged) head. These structural features are common to all detergents and soaps, as described in more detail below. 

The surfactant most commonly used is the anionic detergent sodium lauryl sulfate. Other surfactants that have been used include sodium dodecylbenzene sulfonate [25155-30-0] sodium A/-lauroyl sarcosinate or Gardol [137-16-6] and sodium cocomonoglyceride sulfonate [3694-90-4]. Cationic and nonionic surfactants are not used for several reasons, including incompatibiUty with the abrasive system and lack of high foaming capabiUty. 

Ammonium lauryl sulfate is an anionic surfactant. This means it lowers the surface tension of water, making the water spread more easily. Surfactants are also called wetting agents—in plain terms, they make water wetter. 

Before use, condition the new electrode by employing it in the titration of a sodium lauryl sulfate solution with a solution of Hyamine 1622 or benzetho-nium chloride solution, 0.04 M using a silver-silver chloride reference electrode. During this conditioning, a layer of an insoluble cation-anion complex becomes firmly attached to the plasticized PVC coating rendering it sensitive to both anionic and cationic surfactants. 

Ong et al. [134] found that several hydrophilic anionic, non ionic, or cationic surfactants can alleviate the deleterious effect of magnesium stearate over-mixing on dissolution from capsules when added with the lubricant in a ratio as low as 1 5 (w/w). These successful surfactants were sodium A-lauroyl sarcosinate, sodium stearoyl-2-lactylate, sodium stearate, polox-amer 188, cetylpyridinium chloride, and sodium lauryl sulfate. The lipophilic surfactant glyceryl monostearate did not alleviate the magnesium stearate mixing effect. A reduction in thier particle size was shown to enhance effectiveness, particularly in the case of surfactants with low solubility and slow dissolution rate. 

Figure 7.9.1 The molecular structure of the anionic surfactant sodium lauryl sulfate.

Howard [27] determined dissolved aluminium in seawater by the micelle-enhanced fluorescence of its lumogallion complex. Several surfactants (to enhance fluorescence and minimise interferences), used for the determination of aluminium at very low concentrations (below 0.5 pg/1) in seawaters, were compared. The surfactants tested in preliminary studies were anionic (sodium lauryl sulfate), non-ionic (Triton X-100, Nonidet P42, NOPCO, and Tergital XD), and cationic (cetyltrimethylammonium bromide). Based on the degree of fluorescence enhancement and ease of use, Triton X-100 was selected for further study. Sample solutions (25 ml) in polyethylene bottles were mixed with acetate buffer (pH 4.7, 2 ml) lumogallion solution (0.02%, 0.3 ml) and 1,10-phenanthroline (1.0 ml to mask interferences from iron). Samples were heated to 80 °C for 1.5 h, cooled, and shaken with neat surfactant (0.15 ml) before fluorescence measurements were made. This procedure had a detection limit at the 0.02 pg/1 level. The method was independent of salinity and could therefore be used for both freshwater and seawater samples. 

The ionic field of micells increases the efficiency of photoinduced charge separation. Laser flash photolysis showed a longer lifetime of the e formed by irradiation of a donor molecule (D pyrene, perylene etc.) solubilized in anionic micells such as sodium lauryl sulfate (SDS) than in a non-micell systems 19b). This is why the e is repulsed by the anionic field at the micellar surface into the bulk solution (Eq. (10)). 

Anionic Sodium lauryl sulfate 2-Naphthalene sulfonate sodium Oral drops, granules Oral suspension (see Table 5) (see Table 5)... 

The head groups of these surfactant molecules are negatively charged. The most widely used anionic surfactants are those containing carboxylate groups, such as soaps, sulfonate, and sulfate ions Soaps, which are salts of weak carboxylic acids, are formed by the hydrolysis of fats (triglycerides) by sodium hydroxide. Sulfonates, such as sodium docusate and decane sulfonate, have been widel used in pharmaceutical systems. The most popular alkyl sulfate is sodium lauryl sulfate, which is... 

The effect of various surfactants, the cationics-eetyl trimethyl ammonium bromide (CTAB), and cetyl pyridinium chloride (CPC), the anionic-sodium lauryl sulfate (SLS), and the nonionic-polysorbate 80 (Tween 80), on the solubility and ionization constants of some sparingly soluble weak acids of pharmaceutical interest was studied (Gerakis et al., 1993). Benzoic acid (and its 3-methyl-, 3-nitro-, and 4-tert-butyl-derivatives), acetylsalicylic acid, naproxen, and iopanoic acid were chosen as model drugs. The cationics, CTAB and CPC, were found to considerably increase th< ionization constant of the weak acidS Ka ranged from-0.21 to-3.57), while the anionic, SLS, showed a negligible effect and the nonionic, Tween 80, generally decreased the ionization constants Solubility of the acids increased in aqueous micellar and in acidiLed micellar solutions. 

Hung et al. (1982) developed a sensitive and selective method for silver analysis by reacting silver (I) with 2(3,5-dibromo-2-pyridylazo)-5-diethyl amino phenol in the presence of an anionic surfactant, sodium lauryl sulfate. The ternary complex formed is red and exhibits an absorption peak at 570 nm. Hung and his co-workers employed EDTA as a chelating agent, thereby reducing the interference of common ions. Recoveries were good, and a detection limit of 0.39 ppm of silver was achieved. 

Edelhauser (3) has explained his results on the interaction of anionic surfactants (sodium lauryl sulfate and sodium dodecyl-benzene sulfonate) with a PVAC latex as a two-step mechanism involving surface adsorption followed by surfactant penetration into... 

If a photoactive probe molecule is buried in the core of an anionic micelle, biphotonic excitation generates an upper excited state from which electron ejection to solvent can occur. With pyrene (Py) imbedded within a sodium lauryl sulfate micelle (NaLS), for example, electron ejection to form a hydrated electron occurs, Eq. 6 [27],... 

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