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Larkin TJ, Garvey CJ, Shishmarev D, Kuchel PW, Momot KI. Na + and solute diffusion in aqueous channels of Myverol bicontinuous cubic phase: PGSE NMR and computer modelling. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2017; 55:464-471. [PMID: 27002682 DOI: 10.1002/mrc.4432] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 02/19/2016] [Accepted: 02/23/2016] [Indexed: 06/05/2023]
Abstract
The apparent diffusion coefficients of 23 Na+ ions and the solute 2-fluoroethylamine present in the aqueous domain of a Myverol/water bulk bicontinuous cubic phase (BCP) were measured using pulsed field-gradient spin echo (PGSE) NMR spectroscopy. The measured values were dependent on the diffusion time interval, which is a characteristic of restricted diffusion. The translational motion of 23 Na+ and water in the aqueous channels of a cubic phase were simulated using a Monte-Carlo random walk algorithm, and the simulation results were compared with those from real PGSE NMR experiments. The simulations indicated that diffusion of 23 Na+ ions and water would appear to be restricted even on the shortest timescales available to PGSE NMR experiments. The micro-viscosity of the aqueous domain of the BCPs was estimated from the longitudinal relaxation times of 23 Na+ and 2-fluoroethylamine; this was three times higher than in free solution and suggests one of (but not the only) likely impediments to the release of hydrophilic drugs from stabilised aqueous dispersions of BCPs (cubosomes) when they are used therapeutically in vivo. Monte Carlo simulations of diffusive efflux from cubosomes suggest that the principal impediment to drug release is presented by a surfactant or lipid barrier at the cubosome surface, which separates the BCP aqueous channels from the bulk solution. The dynamics inferred from these studies informs quantitative predictions of drug delivery from cubosomes. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Timothy J Larkin
- Neurosurgery Unit, Department of Clinical Neurosciences, University of Cambridge, United Kingdom
| | - Christopher J Garvey
- Australian Nuclear Science and Technology Organization, Lucas Heights, New South Wales, Australia
| | - Dmitry Shishmarev
- School of Molecular Bioscience, University of Sydney, Sydney, New South Wales, Australia
| | - Philip W Kuchel
- School of Molecular Bioscience, University of Sydney, Sydney, New South Wales, Australia
| | - Konstantin I Momot
- School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology (QUT), Brisbane, Queensland, Australia
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Meikle T, Drummond C, Separovic F, Conn C. Membrane-Mimetic Inverse Bicontinuous Cubic Phase Systems for Encapsulation of Peptides and Proteins. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/bs.abl.2017.01.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
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Falkman P, Aberg C, Clemens A, Sparr E. Lyotropic lipid phases confined in cylindrical pores: structure and permeability. J Phys Chem B 2011; 115:14450-61. [PMID: 22007791 DOI: 10.1021/jp206451c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A model membrane system based on lipid lyotropic phases confined inside the pores of a well-defined scaffold membrane, thereby forming a double-porous membrane structure, is described. The model membrane system is characterized with regard to lipid structure, lipid location, and phase transitions, using small-angle X-ray scattering, differential scanning calorimetry, and confocal microscopy. The system enables studies of transport across oriented lipid bilayers as well as of lipids in confinement. The lipids are shown to be located inside the membrane pores, and the effect of confinement on lipid structure is shown to be small, although dependent on the surface properties of the scaffold membrane. For transport studies, Franz diffusion cells and different types of drugs/dyes are used, and the transport studies are complemented with theoretical modeling. Lipids investigated include monoolein, dioleoyl phosphatidylcholine, dimyristoyl phosphatidylcholine, and E. coli total lipid extract. In the case of monoolein, the lipid structure can be changed from a bicontinuous cubic Ia3d phase to a liquid crystalline lamellar phase, by controlling the osmotic pressure of the surrounding solution through addition of water-soluble polymer. The osmotic pressure can thereby be used as a switch, changing the permeability of the lipid phase up to 100-fold, depending on the properties of the diffusing substance. The large effect of changing the structure implies an alignment of the lamellar phase inside the pores.
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Affiliation(s)
- Peter Falkman
- Physical Chemistry, Chemical Center, Lund University, Lund, Sweden
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Pospiech EM, Geil B, Fujara F, Winter R. The Effect of Incorporation of Gramicidin on the Translational Lipid Diffusion in Bicontinuous Cubic Monoolein/Water Mesophases. Z PHYS CHEM 2009. [DOI: 10.1524/zpch.2009.6058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
The influence of incorporating the polypeptide gramicidin on the lateral mobility of the monoacylglyceride monoolein (MO) in its bicontinuous cubic lipid mesophases is studied applying static field gradient NMR. The effects of gramicidin on the topology, structure and phase behaviour of the system are characterized by small-angle x-ray scattering (SAXS) experiments. On the structural level the experiments show significant shifts in the boundaries of the various mesophases. Measurements of the translational dynamics are restricted to cubic mesophases, where the diffusion coefficients of lipid and additive are determined both by geometrical obstruction and by lipid-protein interaction effects.
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Efrat R, Shalev DE, Hoffman RE, Aserin A, Garti N. Effect of sodium diclofenac loads on mesophase components and structure. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:7590-7595. [PMID: 18547072 DOI: 10.1021/la800603f] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We studied the effect of a model electrolytic drug on intermolecular interactions, conformational changes, and phase transitions in structured discontinuous cubic QL lyotropic liquid crystals. These changes were due to competition with hydration of the lipid headgroups. Structural changes of the phase induced by solubilization loads of sodium diclofenac (Na-DFC) were investigated by directly observing the water, ethanol, and Na-DFC components of the resulting phases using 2H and 23Na NMR. Na-DFC interacted with the surfactant glycerol monoolein (GMO) at the interface while interfering with the mesophase curvature and also competed with hydration of the surfactant headgroups. Increasing quantities of solubilized Na-DFC promoted phase transitions from cubic phase (discontinuous (QL) and bicontinuous (Q)) into lamellar structures and subsequently into a disordered lamellar phase. Quadrupolar coupling of deuterated ethanol by 2H NMR showed that it is located near the headgroups of the lipid and apparently is hydrogen bonded to the GMO headgroups. A phase transition between two lamellar phases (L alpha to L alpha*) was seen by 23Na NMR of Na-DFC at a concentration where the characteristics of the drug change from kosmotropic to chaotropic. These findings show that loads of solubilized drug may affect the structure of its vehicle and, as a result, its transport across skin-blood barriers. The structural changes of the mesophase may also aid controlled drug delivery.
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Affiliation(s)
- Rivka Efrat
- Casali Institute of Applied Chemistry, The Hebrew University of Jerusalem, Safra Campus, Givat Ram, Jerusalem 91904, Israel
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Böhmer R, Faske S, Geil B. Mistimed stimulated echoes and distorted spin-alignment spectra of powdered solids. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2008; 34:32-36. [PMID: 18547790 DOI: 10.1016/j.ssnmr.2008.04.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2008] [Accepted: 04/24/2008] [Indexed: 05/26/2023]
Abstract
It is commonplace that NMR echo maxima appear at times for which the dephasing and the rephasing periods of a pulse sequence are equally long. However, for stimulated echoes a significant time shift from this naively expected echo position can be observed if the dephasing times are smaller than the inverse line width of the NMR spectrum. This effect, which will be observable for any line shape, is evaluated quantitatively for Gaussian and for Pake-like patterns. Comparison of the calculations is made with experimental results from (6)Li- and from (2)H-NMR and excellent agreement is found. In the simultaneous presence of broad and narrow lines, the apparent time shift can give rise to characteristic distortions in spin-alignment spectra. This explains some features previously observed using (7)Li-NMR.
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Affiliation(s)
- Roland Böhmer
- Fakultät für Physik and Interdisziplinäres Zentrum für Magnetische Resonanz, Technische Universität Dortmund, 44221 Dortmund, Germany.
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Efrat R, Aserin A, Garti N. On structural transitions in a discontinuous micellar cubic phase loaded with sodium diclofenac. J Colloid Interface Sci 2008; 321:166-76. [DOI: 10.1016/j.jcis.2008.01.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2007] [Revised: 01/03/2008] [Accepted: 01/04/2008] [Indexed: 10/22/2022]
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Amar-Yuli I, Wachtel E, Shalev DE, Aserin A, Garti N. Low Viscosity Reversed Hexagonal Mesophases Induced by Hydrophilic Additives. J Phys Chem B 2008; 112:3971-82. [DOI: 10.1021/jp711421k] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Idit Amar-Yuli
- Casali Institute of Applied Chemistry, The Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel, Faculty of Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel, and Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Ellen Wachtel
- Casali Institute of Applied Chemistry, The Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel, Faculty of Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel, and Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Deborah E. Shalev
- Casali Institute of Applied Chemistry, The Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel, Faculty of Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel, and Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Abraham Aserin
- Casali Institute of Applied Chemistry, The Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel, Faculty of Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel, and Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Nissim Garti
- Casali Institute of Applied Chemistry, The Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel, Faculty of Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel, and Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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Åberg C, Pairin C, Costa-Balogh FO, Sparr E. Responding double-porous lipid membrane: Lyotropic phases in a polymer scaffold. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1778:549-58. [DOI: 10.1016/j.bbamem.2007.10.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2007] [Revised: 09/28/2007] [Accepted: 10/12/2007] [Indexed: 11/16/2022]
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Amar-Yuli I, Wachtel E, Shalev DE, Moshe H, Aserin A, Garti N. Thermally Induced Fluid Reversed Hexagonal (HII) Mesophase. J Phys Chem B 2007; 111:13544-53. [DOI: 10.1021/jp076662t] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Idit Amar-Yuli
- Casali Institute of Applied Chemistry, The Institute of Chemistry, and Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel, and Faculty of Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ellen Wachtel
- Casali Institute of Applied Chemistry, The Institute of Chemistry, and Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel, and Faculty of Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Deborah E. Shalev
- Casali Institute of Applied Chemistry, The Institute of Chemistry, and Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel, and Faculty of Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Hagai Moshe
- Casali Institute of Applied Chemistry, The Institute of Chemistry, and Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel, and Faculty of Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Abraham Aserin
- Casali Institute of Applied Chemistry, The Institute of Chemistry, and Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel, and Faculty of Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Nissim Garti
- Casali Institute of Applied Chemistry, The Institute of Chemistry, and Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel, and Faculty of Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel
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Capitani D, Yethiraj A, Burnell EE. Memory effects across surfactant mesophases. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:3036-48. [PMID: 17295526 DOI: 10.1021/la062798r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We report a detailed analysis of deuteron NMR spectra of micellar, lamellar, cubic, and hexagonal mesophases in the aqueous non-ionic surfactant system C(12)E(6)/water. Samples are prepared with and without shear. Particular attention is paid to an interesting temperature-driven phase sequence that includes all of the above phases that are studied before and after shear parallel or perpendicular to the magnetic field direction. Surprising memory effects are found across mesophase transitions. These memory effects provide clues to the structure of the various phases.
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Affiliation(s)
- Donatella Capitani
- Institute of Chemical Methodologies, CNR, Research Area of Rome, Via Salaria Km 29-300, Monterotondo Staz, Rome, Italy
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Costa-Balogh FO, Aberg C, Sousa JJS, Sparr E. Drug transport in responding lipid membranes can be regulated by an external osmotic gradient. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:10307-10. [PMID: 16262282 DOI: 10.1021/la051947n] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
In this paper, we demonstrate, for the first time, how an external osmotic gradient can be used to regulate diffusion of solutes across a lipid membrane. We present experimental and theoretical studies of the transport of different solutes across a monoolein membrane in the presence of an external osmotic gradient. The osmotic gradient introduces phase transformations in the membrane, and it causes nonlinear transport behavior. The external gradient can thus act as a kind of switch for diffusive transport in the skin and in controlled release drug formulations.
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Yethiraj A, Capitani D, Burlinson NE, Burnell EE. An NMR study of translational diffusion and structural anisotropy in magnetically alignable nonionic surfactant mesophases. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:3311-3321. [PMID: 15807569 DOI: 10.1021/la046962r] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The diffusion of both water and surfactant components in aqueous solutions of the nonionic surfactant "C12E6"--which includes hexagonal, cubic, lamellar, and micellar mesophases--has been studied by pulsed-field-gradient NMR. Diffusion coefficients were measured in unaligned samples in all of these phases. They were also obtained in the hexagonal and lamellar phases in oriented monodomain samples that were aligned by slow cooling from the micellar phase in an 11.7 T magnet. Measured water and soap diffusion coefficients in the NMR-isotropic cubic and (high-water-content) micellar phases as well as diffusion anisotropy measurements in the magnetically aligned hexagonal phase were quantitatively consistent with the constituent structures of these phases being identical surfactant cylinders, with only the fraction of surface-associated water varying with the water-soap molar ratio. The values of the water and soap diffusion coefficients in the oriented lamellar phase suggest an increase in defects and obstructions to soap diffusion as a function of increasing water content, while those in the low-water-content micellar phase rule out the presence of inverse micelles.
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Affiliation(s)
- Anand Yethiraj
- Chemistry Department, University of British Columbia, 2036 Main Mall, Vancouver, B.C. V6T 1Z1, Canada
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Kraineva J, Narayanan RA, Kondrashkina E, Thiyagarajan P, Winter R. Kinetics of lamellar-to-cubic and intercubic phase transitions of pure and cytochrome c containing monoolein dispersions monitored by time-resolved small-angle X-ray diffraction. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:3559-3571. [PMID: 15807602 DOI: 10.1021/la046873e] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We investigated the effect of incorporation of a small aqueous peripheral membrane protein (cyt c) into the three-dimensional periodic nanochannel structures formed by the lipid monoolein (MO) on its rich phase behavior as a function of temperature, pressure, and protein concentration using synchrotron X-ray small-angle diffraction. By simultaneous use of the pressure-jump relaxation technique and time-resolved synchrotron X-ray diffraction, we also studied the kinetics of various lipid mesophase transformations of the system for understanding the mechanistic pathways of their formation influenced by the protein-lipid interactions. Cyt c incorporated into the bicontinuous cubic phase Ia3d of MO has a significant effect on the lipid structure and the pressure stability of the system already at low protein concentrations. Concentrations higher than 0.2 wt % of cyt c led to an increase in interfacial curvature due to interaction of the protein with the lipid headgroups. This promotes the formation of a new, probably partially micellar cubic phase of crystallographic space group P4(3)32. Upon pressurization, the P4(3)32 phase undergoes a phase transition to a cubic Pn3m phase with smaller partial specific volume. Increase in protein concentration increases the pressure stability of the P4(3)32 phase. The formation of this phase from the cubic phase Pn3m is a slow process taking many seconds and having a time lag in the beginning. It seems to occur as a two-state process without ordered intermediate states. At temperatures above 60 degrees C, the P4(3)32 phase is unable to accommodate the unfolded protein and transforms to a bicontinuous cubic Ia3d phase. Time-resolved small-angle X-ray scattering studies show that the L(alpha) --> Ia3d transition in pure MO dispersions under limited hydration conditions occurs within a time interval of 1 s at 35 degrees C preceded by a lag phase of 1.5 s. The Ia3d cubic phase initially forms with a much larger lattice constant due to hydration and experiences an initially lower curvature that relaxes within about 1 s. Interestingly, no other cubic phases are involved as intermediates in the transition, i.e., the gyroid cubic phase is able to form directly from the L(alpha) phase. The mechanism behind the L(alpha) --> Ia3d transition in pure MO dispersions has been discussed within the framework of recent stalk models for membrane fusion. In the presence of cyt c, the L(alpha) --> Ia3d transition is much slower. The rather long relaxation times of the order of seconds are probably due to a kinetic trapping of the system and limitation by the transport and redistribution of water and lipid in the evolving new lipid phases. We also studied the transition from the pure lamellar L(alpha) phase to the Ia3d-P4(3)32 two phase region and observed a rather complex transition behavior with transient lamellar and cubic intermediate states.
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Affiliation(s)
- Julia Kraineva
- Department of Chemistry, Physical Chemistry I, University of Dortmund, Otto-Hahn Strasse 6, D-44221 Dortmund, Germany
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Håkansson P, Westlund PO. Nuclear magnetic relaxation study of the microstructure of a bicontinuous cubic phase. Phys Chem Chem Phys 2004. [DOI: 10.1039/b408003c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Gröger S, Rittig F, Stallmach F, Almdal K, Štěpánek P, Papadakis CM. A pulsed field gradient nuclear magnetic resonance study of a ternary homopolymer/diblock copolymer blend in the bicontinuous microemulsion phase. J Chem Phys 2002. [DOI: 10.1063/1.1481058] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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17
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Pulsed field gradient MAS-NMR studies of the mobility of carboplatin in cubic liquid-crystalline phases. Chem Phys Lett 2002. [DOI: 10.1016/s0009-2614(02)00468-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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18
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Czeslik C, Winter R. Structure of water confined in the gyroid cubic phase of the lipid monoelaidin. J Mol Liq 2002. [DOI: 10.1016/s0167-7322(01)00332-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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