Microscopy, SAXD, and NMR studies of phase behavior of the monoolein-diolein-water system
(2000) In Langmuir 16(26). p.10044-10054- Abstract
- The phase behavior of the ternary monoolein (MO)-diolein (DO)-water ((H2O)-H-2) system is presented. The experimental phase behavior and microstructure are studied by a combination of polarizing microscopy, small-angle X-ray diffraction, and NMR methods. Monoolein forms extensive reversed bicontinuous cubic liquid crystalline phases (C) that are in equilibrium with a lamellar liquid crystalline phase (L-alpha) on the water-poor side and with excess water on the other side. The presence of small amounts of DO in the MO-water system is sufficient to destabilize the C and L-alpha liquid crystalline phases. Formation of a reversed hexagonal (HII) phase from the cubic phase occurs at a lower transition temperature than that reported for the... (More)
- The phase behavior of the ternary monoolein (MO)-diolein (DO)-water ((H2O)-H-2) system is presented. The experimental phase behavior and microstructure are studied by a combination of polarizing microscopy, small-angle X-ray diffraction, and NMR methods. Monoolein forms extensive reversed bicontinuous cubic liquid crystalline phases (C) that are in equilibrium with a lamellar liquid crystalline phase (L-alpha) on the water-poor side and with excess water on the other side. The presence of small amounts of DO in the MO-water system is sufficient to destabilize the C and L-alpha liquid crystalline phases. Formation of a reversed hexagonal (HII) phase from the cubic phase occurs at a lower transition temperature than that reported for the MO-water system. Within the cubic region, the diamond cubic phase, CD, is less stable than the gyroid type, C-G. The solubility of DO increases within this phase when the MO content increases, and the phase reaches its maximum stability at 4 wt % DO. The large HII-phase formed in the ternary system is in equilibrium with water, and it solubilizes about 30 wt % DO within its stability range. A stable dispersion is formed at even higher DO concentrations. An ideal swelling of the HII-phase with increasing polar volume fraction is observed, whereas the length of the hydrocarbon chains along the hexagonal faces is constant. We measure a slight change of the average area per molecule in the H-II-phase with DO concentration. The formation and stability of the liquid crystalline phases can be qualitatively understood from the self-aggregation model, using the geometrical packing parameter of the lipids. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/7508751
- author
- Borné, Johanna LU ; Nylander, Tommy LU and Khan, Ali LU
- organization
- publishing date
- 2000
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Langmuir
- volume
- 16
- issue
- 26
- pages
- 10044 - 10054
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- wos:000166161700016
- scopus:0034514818
- ISSN
- 0743-7463
- DOI
- 10.1021/la000619e
- language
- English
- LU publication?
- yes
- id
- 7c2e1306-8911-457f-a46d-8d36bcfcd42d (old id 7508751)
- date added to LUP
- 2016-04-01 12:35:03
- date last changed
- 2022-03-21 06:21:46
@article{7c2e1306-8911-457f-a46d-8d36bcfcd42d,
abstract = {{The phase behavior of the ternary monoolein (MO)-diolein (DO)-water ((H2O)-H-2) system is presented. The experimental phase behavior and microstructure are studied by a combination of polarizing microscopy, small-angle X-ray diffraction, and NMR methods. Monoolein forms extensive reversed bicontinuous cubic liquid crystalline phases (C) that are in equilibrium with a lamellar liquid crystalline phase (L-alpha) on the water-poor side and with excess water on the other side. The presence of small amounts of DO in the MO-water system is sufficient to destabilize the C and L-alpha liquid crystalline phases. Formation of a reversed hexagonal (HII) phase from the cubic phase occurs at a lower transition temperature than that reported for the MO-water system. Within the cubic region, the diamond cubic phase, CD, is less stable than the gyroid type, C-G. The solubility of DO increases within this phase when the MO content increases, and the phase reaches its maximum stability at 4 wt % DO. The large HII-phase formed in the ternary system is in equilibrium with water, and it solubilizes about 30 wt % DO within its stability range. A stable dispersion is formed at even higher DO concentrations. An ideal swelling of the HII-phase with increasing polar volume fraction is observed, whereas the length of the hydrocarbon chains along the hexagonal faces is constant. We measure a slight change of the average area per molecule in the H-II-phase with DO concentration. The formation and stability of the liquid crystalline phases can be qualitatively understood from the self-aggregation model, using the geometrical packing parameter of the lipids.}},
author = {{Borné, Johanna and Nylander, Tommy and Khan, Ali}},
issn = {{0743-7463}},
language = {{eng}},
number = {{26}},
pages = {{10044--10054}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Langmuir}},
title = {{Microscopy, SAXD, and NMR studies of phase behavior of the monoolein-diolein-water system}},
url = {{http://dx.doi.org/10.1021/la000619e}},
doi = {{10.1021/la000619e}},
volume = {{16}},
year = {{2000}},
}