Micellar-enhanced ultrafiltration (MEUF) of zinc ions (Zn2+) from aqueous solutions using single anionic surfactant sodium dodecyl sulphate (SDS) at low critical micelle concentrations (cmc) (0.2×cmc – 3×cmc) was investigated. When the initial SDS concentration was below the cmc, unexpectedly high rejection (97.5%) was obtained due to concentration polarisation occurring near the membrane-solut...

At low concentrations, surfactant molecules are unassociated monomers. As the concentration of surfactant is increased, the attractive and repulsive forces between the molecules cause self-aggregation to occur resulting in the formation of monolayers or micelles (Figure 1). The concentration at which these micelles form is called the critical micelle concentration (cmc). The characteristics of ...

We present a new theoretical approach to the kinetics of micelle formation in surfactant solutions, in which the various stages of aggregation are treated as constrained paths on a single free-energy landscape. Three stages of well-separated time scales are distinguished. The first and longest stage involves homogeneous nucleation of micelles, for which we derive the size of the critical nuclei...

Free energy of transfer, DeltaG(w-->m), from water phase to a sodium dodecyl sulfate (SDS) micelle core has been calculated for a series of hydrophobic solutes originally immiscible with water by thermodynamic integration method combined with molecular dynamics calculations. The calculated free energy of transfer is in good correspondence to the experiment as well as the theoretical free energy...

The proton magnetic resonance spectrum of DL-a!-lecithin at 100 MHz in CHCJ solvent is reported. An analysis of the spectrum is made. The chemical shifts of the N-(CH& protons and the resonance peak associated with the condensed water molecule showed concentration dependence with the latter showing the more pronounced response. These chemical shift changes are interpreted in terms of micelle fo...

single-walled carbon nanotubes (swnts) are among the promising nano-devices for delivery of therapeutic agents. yet the drastic hydrophobic natures of swnts make their handling and hence application difficult.several researches have been conducted to make them more hydrophilic and water dispersible and less toxic. among the different approaches, dispersion methods exploit different reagents suc...