68 research outputs found
Solubilization in micellar systems. Analytical and environmental applications
Abstract: Surfactant-based separation techniques largely exploit the solubilization power of micelles and other amphiphilic aggregates towards a great variety of hydrophilic and hydrophobic solutes. Micellar extraction, based on the cloud-point phenomenon, and micellar ultrafiltration have been succesfilly applied for preconcentration and removal of organic and inorganic analytes of environmental concern from aqueous media. In particular, the recent development of chelating surfactant aggregates allows to perform very selective demetallation treatments. The factors which control the separation efficiencies of these methods are examined and discussed
Characterization of CdSe nanocrystals coated with amphiphiles. A capillary electrophoresis study
We have synthesized CdSe nanocrystals (NCs) possessing a trioctylphosphine surface passivation layer and modified with amphiphilic molecules to form a surface bilayer. The NCs covered with single amphiphiles are not stable in aqueous solution, but a mixed amphiphilic system is shown to provide stability in solution over several months. The solutions of the modified NCs were characterized by UV-Vis absorbance, photoluminescence, and transmission electron microscopy. An electrophoretic study revealed two operational modes. The first relies on the enrichment of NCs using a micellar plug as a tool. The accumulation of NCs at the plug-electrolyte buffer interface results in a sharp peak. By controlling the electrophoretic conditions, nanocrystals were forced to exit a micellar plug into an electrolyte buffer. We conclude that a system consisting of modified nanocrystals and a micellar plug can act as a mixed pseudomicellar system, where modified nanocrystals play the role of pseudomicelles
Electron-transfer kinetics of 4,4'-bis(alkoxycarbonyl)-2,2'-bipyridine-iron complexes in micellar solution.
Interaction of sodium alginate with cetyltrimethylammonium bromide in aqua-organic mixed solvents: influence of temperatures and compositions
Surface Activity and Micelle Formation of Alkyl- Substituted Aza-Crown Ethers and Their Metal Ion Complexes
Diffusion processes in amphiphilic aggregate systems
The diffusion properties of aggregates of amphiphilic mols. (e.g., micelles, microemulsion) are discussed. The interaction of these organized assemblies with water-sparingly sol. org. compds. and ions and the consequent influence on the transport of these species is examd. as well as their effect on the transfer of solutes through a membrane
Ion interaction high-performance liquid chromatography and micellar electrokinetic capillary chromatography: two complementary techniques for the separation of aromatic sulfonated compounds
Selective Recovery of Uranium(VI) from Acqueous acid solutions using Micellar Ultrafiltration.
Influences of alcohol and diol on the aggregation behaviour, modes of interaction and the thermodynamic properties of the mixture of bromocresol green dye and sodium dodecyl sulphate at numerous temperatures
Quantitative removal of uranyl ions from aqueous solution using micellar enhanced ultra filtration
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