| Autor: |
C. Larpent, Marc Hebrant, P. Mettelin, X. Chasseray, C. Tondre, Jean-Pierre Joly |
| Rok vydání: |
1993 |
| Předmět: |
|
| Zdroj: |
Colloids and Surfaces A: Physicochemical and Engineering Aspects. 75:257-267 |
| ISSN: |
0927-7757 |
| DOI: |
10.1016/0927-7757(93)80437-j |
| Popis: |
Reversed micelles of diethylhexyl sodium sulphosuccinate (AOT) are used in this work as mobile carriers to transport amino acids between a source (S) and a receiving (R) aqueous phase across an organic liquid membrane (M) (isooctane). For most experiments the aqueous and organic phases were those of a pre-equilibrated Winsor II system. Semipermeable membranes have been introduced between the S and M phases as well as between the M and R phases for technical reasons. The rates of transport of p -iodophenylalanine and tryptophan were compared and discussed in relation to their partition coefficients between water and the AOT palisade layer, showing completely different behaviour between the two amino acids. As the selectivity of the transport process may depend on the water content of the membrane phase and also on the carrier/solute interactions, we have investigated the rate of water uptake by the AOT reversed micelles as well as the influence of the ionization state of amino acids. The last part of the work is concerned with an attempt to perform enantioselective transports using chiral AOT. The analysis of the receiving phase required in that case a chromatographic resolution of amino acid enantiomers. This resolution was affected by the nature of the background salt, which had to be specifically adapted for this purpose. The failure of these experiments in producing enantiomeric enrichments suggests that the rigidity of the surfactant film is not sufficient to permit chiral recognition in that case. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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