Small-angle neutron scattering from mixtures of sodium dodecyl sulfate and a cationic, bolaform surfactant containing azobenzene
This paper reports on the microstructures formed in aqueous solutions containing mixtures of sodium dodecyl sulfate (SDS) and a photosensitive, bolaform surfactant, bis(trimethylammoniumhexyloxy)azobenzene dibromide (BTHA). By using quasi-elastic light scattering and small-angle neutron scattering,...
Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 21(2005), 14 vom: 05. Juli, Seite 6131-6 |
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1. Verfasser: | |
Weitere Verfasser: | , , |
Format: | Aufsatz |
Sprache: | English |
Veröffentlicht: |
2005
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Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Azo Compounds Surface-Active Agents Sodium Dodecyl Sulfate 368GB5141J azobenzene F0U1H6UG5C |
Zusammenfassung: | This paper reports on the microstructures formed in aqueous solutions containing mixtures of sodium dodecyl sulfate (SDS) and a photosensitive, bolaform surfactant, bis(trimethylammoniumhexyloxy)azobenzene dibromide (BTHA). By using quasi-elastic light scattering and small-angle neutron scattering, we determined that aqueous solutions containing SDS and the trans isomer of BTHA (0.1 wt % total surfactant, 15 mol % BTHA, 85 mol % SDS) form vesicles with average hydrodynamic diameters of 1350 +/- 50 angstroms and bilayer thicknesses of 35 +/- 2 angstroms. The measured bilayer thickness is consistent with a model of the vesicle bilayer in which the trans isomer of BTHA spans the bilayer. Upon illumination with UV light, the BTHA underwent photoisomerization to produce a cis-rich photostationary state (80% cis isomer). We measured this photoisomerization to drive the reorganization of vesicles into cylindrical aggregates with cross-sectional radii of 19 +/- 3 angstroms and average hydrodynamic diameters of 240 +/- 50 angstroms. Equilibration of the cis-rich solution in the dark at 25 degrees C for 12 h or illumination of the solution with visible light leads to the recovery of the trans-rich photostationary state of the solution and the reformation of vesicles, thus demonstrating the potential utility of this system as the basis of a tunable fluid |
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Beschreibung: | Date Completed 21.08.2006 Date Revised 21.11.2013 published: Print Citation Status MEDLINE |
ISSN: | 1520-5827 |