Sodium dodecyl sulfate mechanical properties

Additives. Sodium dodecyl sulfate (SDS), 5.0 M urea and 0.1 M betaine were added to the FAM solution to disrupt the association process to help understand the mechanism. Betaine had previously shown some dissociative properties, and urea is effective in preventing association caused by H-bonding. Solutions at different alkalinities were produced as before and ultrafiltered. 

Human taste response is modified by several plant-derived substances. The detergent sodium dodecyl sulfate, as well as triterpene saponins from the leaves of several plant species (most notably Gymnema sylvestre and Ziziphus jujuba) will temporarily inhibit the sweet taste sensation in man the duration of the effect being about one hour for G. sylvestre and about fifteen minutes for Z. jujuba. The mechanism of action seems to be related, in part, to the surfactant properties of the materials. Structures of the modifiers and possible mechanisms of action are discussed. 

Sodium dodecyl sulfate, the gymnemic acids and the ziziphins have all been termed "surface active" taste modifiers because they all possess detergent-like properties. These molecules all have a polar and a non-polar end and they are capable of penetrating the phospholipid membranes that are believed to be components of sweetness receptors. Any speculation about the mechanism of action of these substances must take into account the experimental observations concerning miraculin, monellin, and thaumatin, which were presented at the beginning of this article. Those observations suggested that transport of the modifier to the cell s interior was not occurring and the inhibition effect is manifested at the surface of the cell. 

Mo, X., and X. Sun. 2000. Thermal and mechanical properties of plastics molded from sodium dodecyl sulfate-modified soy protein isolates. Journal cf Polymers and the Environment 8(4) 161-166. 

Earlier [22], the applicability of the model proposed above (Section 1.6) to binary mixtures of common pharmaceutical excipients and sodium dodecyl sulfate (SDS) was investigated. SDS was chosen for study as its mechanical properties are vastly different from the other excipients -indeed more so than those selected by Wu et al. [20] and Tye et at [10]. Secondly, SDS for various reasons is sometimes incorporated into pharmaceutical formulations and degrades the tabletability of such formulations. 

It is worth emphasizing here that while the structural-rheological properties (i.e., mechanical strength) of the interfacial adsorption layer play a determining role in the stability of the system toward coalescence, they alone may not be sufficient for complete stabilization. The prevention of coagulation also requires that the structural-mechanical barrier formed is lyophilic (hydrophilic) with respect to the surrounding polar liquid. The latter can be achieved by the introduction of common surfactants, for example, sodium dodecyl sulfate (SDS). 

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