Sodium cetyl sulfate solution

Chemical Designations - Synonyms Cetyl sodium sulfate Sodium cetyl sulfate solution Chemical Formula CH3(CH2),4CHj0S03Na-H20. 

Selenium Dioxide Selenium Dioxide Sodium Cetyl Sulfate Solution Hexadecyl Sulfite,... 

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. 

Unfortunately, no such simple solution is available for the ESA effect at the high frequencies at which it is ciu-rently used. Goetz and El-Aasser (24) attempted to compare the electroacoustic and electrophoretic behavior of concentrated miniemulsion systems of toluene in water, stabilized by cetyl alcohol and sodium laiuyl sulfate. They concluded that the simple correction which works well for CVP does not produce a similar reconciliation in the case of the ESA effect. Their conclusions are, however, suspect because of uncertainties arising from the dilution of the emulsion system this can so easily lead to changes in siuface properties, no matter how carefully it is done. Texter s results (34) referred to above are perhaps more definitive in this case. He showed that in the range from 2 to 5% by volume where his particles showed a nonlinear dependence of the ESA signal on volume fraction, the Levine and Neale model (3 8) was unable to account for the nonlinearity. His particles were, however, nonspherical and that may at least partially explain the discrepancy. 

From Stockmann and Schwarz (1999). Oil-in-water emulsions were prepared with 20% corn oil and 1% emulsifier in 0.2 M acetate buffer (pH 5). SDS = sodium dodecyl sulfate, CTAB = cetyltrimethyl ammonium bromide, Brij 58 = polyoxyethylene 20 cetyl ether, PHLC = partially hydrolysed soybean lecithin. Amount of solute solubilized in oil lipid phase of emulsions was calculated from the difference between the total amount in the system and the amount of oil solubilized in the aqueous phase determined by ultrafiltration and semiequiUbrium dialysis. 

In a pioneering study, Nakamura et al. have pointed out enhancement of photochemical dimerization of ACN in micelles compared to dimerization in solution phase.They employed sodium dodecyl sulfate (SDS) as an ionic surfactant and polyoxyethylene-polyoxypropylene cetyl ether (PBC-34) as a nonionic surfactant. In general, the dimerization occurred efficiently in both of the micelles even with concentrations of ACN as low as 1.9 mmol, whereas dimerization in benzene solution was nil. Under concentrations of 5 30 mmol of ACN, the cisoid/transoid ratio in PBC-30 was ca. 0.8 and independent on the initial concentration of ACN, while that in SDS was as high as 2.7, showing dependence of the ratio on the surfactant used. 

Cellulose Nitrate Solution Cetyl Sodium Sulfate... 

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