Cyclodextrin-Surfactant Coassembly Depends on the Cyclodextrin Ability To Crystallize.
(2012) In Langmuir 28(5). p.2387-2394- Abstract
- Full equilibrium phase diagrams are presented for two ternary systems composed of the cationic surfactant dodecyltrimethylammonium bromide (DTAB), water (D(2)O), and a cyclodextrin, either β-cyclodextrin (β-CD) or (2-hydroypropyl)-β-cyclodextrin (2HPβCD). (2)H NMR, SAXS, WAXS, and visual examination were used to determine the phase boundaries and characterize the nature of the phases formed. Additionally, diffusion (1)H NMR was used to investigate parts of the diagrams. The water solubility of 2HPβCD is 80% (w/w), whereas it is only 1.85% (w/w) for β-CD. Solubility increases for both species upon complexation with DTAB; while the increase is minute for 2HPβCD, it is dramatic for β-CD. Both systems displayed an isotropic liquid solution... (More)
- Full equilibrium phase diagrams are presented for two ternary systems composed of the cationic surfactant dodecyltrimethylammonium bromide (DTAB), water (D(2)O), and a cyclodextrin, either β-cyclodextrin (β-CD) or (2-hydroypropyl)-β-cyclodextrin (2HPβCD). (2)H NMR, SAXS, WAXS, and visual examination were used to determine the phase boundaries and characterize the nature of the phases formed. Additionally, diffusion (1)H NMR was used to investigate parts of the diagrams. The water solubility of 2HPβCD is 80% (w/w), whereas it is only 1.85% (w/w) for β-CD. Solubility increases for both species upon complexation with DTAB; while the increase is minute for 2HPβCD, it is dramatic for β-CD. Both systems displayed an isotropic liquid solution (L(1)) one-phase region, the extension of which differs extensively between the two systems. Additionally, the DTAB:2HPβCD:water system also comprised a normal hexagonal (H(1)) area, which was not found for the DTAB:β-CD:water system. In the DTAB:β-CD:water system, on the other hand, we found cocrystallization of DTAB and β-CD. From this work we conclude that DTAB and CD molecules form 1:1 inclusion complexes with high affinities. Moreover, we observed indications of an association of 2HPβCD to DTAB micelles in the isotropic solution phase, which was not the case for β-CD and DTAB micelles. This is, to our knowledge, the first complete phase diagrams of surfactant-CD mixtures; as a novel feature it includes the observation of cocrystallization at high concentrations. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/2336709
- author
- Carlstedt, Jonas LU ; Bilalov, Azat LU ; Krivtsova, Elena ; Olsson, Ulf LU and Lindman, Björn LU
- organization
- publishing date
- 2012
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Langmuir
- volume
- 28
- issue
- 5
- pages
- 2387 - 2394
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- wos:000299864500012
- pmid:22217424
- scopus:84856713941
- pmid:22217424
- ISSN
- 0743-7463
- DOI
- 10.1021/la203673w
- language
- English
- LU publication?
- yes
- id
- 410a2fba-556f-4794-afa5-d9dd7b4a58f7 (old id 2336709)
- date added to LUP
- 2016-04-01 11:03:24
- date last changed
- 2022-01-26 05:05:05
@article{410a2fba-556f-4794-afa5-d9dd7b4a58f7,
abstract = {{Full equilibrium phase diagrams are presented for two ternary systems composed of the cationic surfactant dodecyltrimethylammonium bromide (DTAB), water (D(2)O), and a cyclodextrin, either β-cyclodextrin (β-CD) or (2-hydroypropyl)-β-cyclodextrin (2HPβCD). (2)H NMR, SAXS, WAXS, and visual examination were used to determine the phase boundaries and characterize the nature of the phases formed. Additionally, diffusion (1)H NMR was used to investigate parts of the diagrams. The water solubility of 2HPβCD is 80% (w/w), whereas it is only 1.85% (w/w) for β-CD. Solubility increases for both species upon complexation with DTAB; while the increase is minute for 2HPβCD, it is dramatic for β-CD. Both systems displayed an isotropic liquid solution (L(1)) one-phase region, the extension of which differs extensively between the two systems. Additionally, the DTAB:2HPβCD:water system also comprised a normal hexagonal (H(1)) area, which was not found for the DTAB:β-CD:water system. In the DTAB:β-CD:water system, on the other hand, we found cocrystallization of DTAB and β-CD. From this work we conclude that DTAB and CD molecules form 1:1 inclusion complexes with high affinities. Moreover, we observed indications of an association of 2HPβCD to DTAB micelles in the isotropic solution phase, which was not the case for β-CD and DTAB micelles. This is, to our knowledge, the first complete phase diagrams of surfactant-CD mixtures; as a novel feature it includes the observation of cocrystallization at high concentrations.}},
author = {{Carlstedt, Jonas and Bilalov, Azat and Krivtsova, Elena and Olsson, Ulf and Lindman, Björn}},
issn = {{0743-7463}},
language = {{eng}},
number = {{5}},
pages = {{2387--2394}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Langmuir}},
title = {{Cyclodextrin-Surfactant Coassembly Depends on the Cyclodextrin Ability To Crystallize.}},
url = {{http://dx.doi.org/10.1021/la203673w}},
doi = {{10.1021/la203673w}},
volume = {{28}},
year = {{2012}},
}