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Yao Y, Catalini S, Foggi P, Mezzenga R. Water-lipid interface in lipidic mesophases with excess water. Faraday Discuss 2024; 249:469-484. [PMID: 37786338 PMCID: PMC10845009 DOI: 10.1039/d3fd00118k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Accepted: 06/27/2023] [Indexed: 10/04/2023]
Abstract
This study investigates the influence of excess water on the lipidic mesophase during the phase transition from diamond cubic phase (Pn3̄m) to reverse hexagonal phase (HII). Using a combination of small angle X-ray scattering (SAXS), broadband dielectric spectroscopy (BDS), and Fourier transform infrared (FTIR) techniques, we explore the dynamics of lipids and their interaction with water during phase transition. Our BDS results reveal three relaxation processes originating from lipids, all of which exhibit a kink during the phase transition. With the excess water, these processes accelerate due to the plasticizing effect of water. Additionally, our results demonstrate that the headgroups in the HII phase are more densely packed than those in the Pn3̄m phase, which agrees with the FTIR results. Meanwhile, we investigate the influence of excess water on the lipid headgroups, the H-bond network of water, the lipid tail, and the interface carbonyl group between the head and tail of the lipid molecule. The results indicate that excess water permeates the lipid interface and forms additional hydrogen bonds with the carbonyl groups. As a result, the headgroups are more flexible in a lipidic mesophase with excess water than those in mesophases without excess water.
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Affiliation(s)
- Yang Yao
- Department of Health Sciences and Technology, ETH Zürich, 8092 Zürich, Switzerland.
| | - Sara Catalini
- European Laboratory for Non-Linear Spectroscopy, LENS, 50019 Florence, Italy
- Department of Physic and Geology, University of Perugia, 06123 Perugia, Italy
- CNR-INO, National Research Council-National Institute of Optics, 50125 Florence, Italy
| | - Paolo Foggi
- European Laboratory for Non-Linear Spectroscopy, LENS, 50019 Florence, Italy
- CNR-INO, National Research Council-National Institute of Optics, 50125 Florence, Italy
- Department of Chemistry, Biology and Biotechnology, University of Perugia, 06123 Perugia, Italy
| | - Raffaele Mezzenga
- Department of Health Sciences and Technology, ETH Zürich, 8092 Zürich, Switzerland.
- Department of Materials, ETH Zürich, 8093 Zürich, Switzerland
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2
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Yao Y, Catalini S, Kutus B, Hunger J, Foggi P, Mezzenga R. Probing Water State during Lipidic Mesophases Phase Transitions. Angew Chem Int Ed Engl 2021; 60:25274-25280. [PMID: 34558162 PMCID: PMC9298331 DOI: 10.1002/anie.202110975] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/16/2021] [Indexed: 11/30/2022]
Abstract
We investigate the static and dynamic states of water network during the phase transitions from double gyroid (Ia3‾d
) to double diamond (Pn3‾m
) bicontinuous cubic phases and from the latter to the reverse hexagonal (HII) phase in monolinolein based lipidic mesophases by combining FTIR and broadband dielectric spectroscopy (BDS). In both cubic(s) and HII phase, two dynamically different fractions of water are detected and attributed to bound and interstitial free water. The dynamics of the two water fractions are all slower than bulk water due to the hydrogen‐bonds between water molecules and the lipid's polar headgroups and to nanoconfinement. Both FTIR and BDS results suggest that a larger fraction of water is hydrogen‐bonded to the headgroup of lipids in the HII phase at higher temperature than in the cubic phase at lower temperature via H‐bonds, which is different from the common expectation that the number of H‐bonds should decrease with increase of temperature. These findings are rationalized by considering the topological ratio of interface/volume of the two mesophases.
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Affiliation(s)
- Yang Yao
- Department of Health Sciences and Technology, ETH Zürich, Schmelzbergstrasse 9, 8092, Zürich, Switzerland
| | - Sara Catalini
- European Laboratory for Non-Linear Spectroscopy, LENS, Via Nello Carrara 1, 50019, Florence, Italy
| | - Bence Kutus
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Johannes Hunger
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Paolo Foggi
- European Laboratory for Non-Linear Spectroscopy, LENS, Via Nello Carrara 1, 50019, Florence, Italy.,Department of Chemistry, University of Perugia, Via Elce di Sotto 8, 06123, Perugia, Italy
| | - Raffaele Mezzenga
- Department of Health Sciences and Technology, ETH Zürich, Schmelzbergstrasse 9, 8092, Zürich, Switzerland.,Department of Materials, ETH Zürich, Wolfgang-Pauli-Strasse 10, 8093, Zürich, Switzerland
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Yao Y, Catalini S, Kutus B, Hunger J, Foggi P, Mezzenga R. Probing Water State during Lipidic Mesophases Phase Transitions. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202110975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Yang Yao
- Department of Health Sciences and Technology ETH Zürich Schmelzbergstrasse 9 8092 Zürich Switzerland
| | - Sara Catalini
- European Laboratory for Non-Linear Spectroscopy, LENS Via Nello Carrara 1 50019 Florence Italy
| | - Bence Kutus
- Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
| | - Johannes Hunger
- Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
| | - Paolo Foggi
- European Laboratory for Non-Linear Spectroscopy, LENS Via Nello Carrara 1 50019 Florence Italy
- Department of Chemistry University of Perugia Via Elce di Sotto 8 06123 Perugia Italy
| | - Raffaele Mezzenga
- Department of Health Sciences and Technology ETH Zürich Schmelzbergstrasse 9 8092 Zürich Switzerland
- Department of Materials ETH Zürich Wolfgang-Pauli-Strasse 10 8093 Zürich Switzerland
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Knežević A, Dokli I, Sapunar M, Šegota S, Baumeister U, Lesac A. Induced smectic phase in binary mixtures of twist-bend nematogens. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2018; 9:1297-1307. [PMID: 29765808 PMCID: PMC5942249 DOI: 10.3762/bjnano.9.122] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 03/22/2018] [Indexed: 05/28/2023]
Abstract
The investigation of liquid crystal (LC) mixtures is of great interest in tailoring material properties for specific applications. The recent discovery of the twist-bend nematic phase (NTB) has sparked great interest in the scientific community, not only from a fundamental viewpoint, but also due to its potential for innovative applications. Here we report on the unexpected phase behaviour of a binary mixture of twist-bend nematogens. A binary phase diagram for mixtures of imino-linked cyanobiphenyl (CBI) dimer and imino-linked benzoyloxy-benzylidene (BB) dimer shows two distinct domains. While mixtures containing less than 35 mol % of BB possess a wide temperature range twist-bend nematic phase, the mixtures containing 55-80 mol % of BB exhibit a smectic phase despite that both pure compounds display a Iso-N-NTB-Cr phase sequence. The phase diagram shows that the addition of BB of up to 30 mol % significantly extends the temperature range of the NTB phase, maintaining the temperature range of the nematic phase. The periodicity, obtained by atomic force microscopy (AFM) imaging, is in the range of 6-7 nm. The induction of the smectic phase in the mixtures containing 55-80 mol % of BB was confirmed using polarising optical microscopy (POM), differential scanning calorimetry (DSC) and X-ray diffraction. The origin of the intercalated smectic phase was unravelled by combined spectroscopic and computational methods and can be traced to conformational disorder of the terminal chains. These results show the importance of understanding the phase behaviour of binary mixtures, not only in targeting a wide temperature range but also in controlling the self-organizing processes.
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Affiliation(s)
- Anamarija Knežević
- Division of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Irena Dokli
- Division of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Marin Sapunar
- Division of Physical Chemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Suzana Šegota
- Division of Physical Chemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Ute Baumeister
- Institute of Chemistry, Physical Chemistry, Martin Luther University Halle-Wittenberg, von-Danckelmann-Platz 4, 06120 Halle, Germany
| | - Andreja Lesac
- Division of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
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Submicron complex lipid carriers for curcumin delivery to intestinal epithelial cells: Effect of different emulsifiers on bioaccessibility and cell uptake. Int J Pharm 2015; 494:357-69. [DOI: 10.1016/j.ijpharm.2015.08.039] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 08/12/2015] [Accepted: 08/13/2015] [Indexed: 01/26/2023]
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Dong YD, Larson I, Barnes TJ, Prestidge CA, Boyd BJ. Adsorption of nonlamellar nanostructured liquid-crystalline particles to biorelevant surfaces for improved delivery of bioactive compounds. ACS APPLIED MATERIALS & INTERFACES 2011; 3:1771-1780. [PMID: 21506614 DOI: 10.1021/am2003069] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The adsorption of nanostructured lyotropic liquid-crystal particles, cubosomes and hexosomes, at surfaces was investigated for potential use in surface-specific agrochemical delivery. Adsorption of phytantriol (PHYT) and glyceryl monooleate (GMO)-based cubosomes and hexosomes, stabilized using Pluronic F127, at tristearin-coated (model leaf surface) and uncoated zinc selenide surfaces was studied using attenuated total reflectance Fourier transform IR (ATR-FTIR) spectroscopy, by quantifying the IR absorbance due to the lipid components of the particles over time. The delivery of an encapsulated hydrophobic model herbicide [dichlorodiphenyldichloroethylene (DDE)] was also examined on the model and real leaf surfaces. The adsorption behavior of the particles by ATR-FTIR was dependent on the internal nanostructure and lipid composition, with PHYT cubosomes adsorbing more avidly at tristearin surfaces than GMO-based cubosomes or hexosomes. There was a direct correlation between DDE associated with the surfaces and the particle adsorption observed in the ATR-FTIR study, strongly implicating particle adsorption with the delivery efficiency. Differences between the mode of interaction of the Pluronic stabilizer with the different lipids and particle nanostructures were proposed to lead to differences in the particle adsorption behavior.
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Affiliation(s)
- Yao-Da Dong
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University (Parkville Campus), 381 Royal Pde, Parkville, Victoria, Australia
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Kapoor S, Werkmüller A, Denter C, Zhai Y, Markgraf J, Weise K, Opitz N, Winter R. Temperature-pressure phase diagram of a heterogeneous anionic model biomembrane system: results from a combined calorimetry, spectroscopy and microscopy study. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:1187-95. [PMID: 21262194 DOI: 10.1016/j.bbamem.2011.01.011] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Revised: 01/17/2011] [Accepted: 01/19/2011] [Indexed: 01/13/2023]
Abstract
By using Fourier transform infrared (FT-IR) spectroscopy in combination with differential scanning calorimetry (DSC) coupled with pressure perturbation calorimetry (PPC), ultrasound velocimetry, Laurdan fluorescence spectroscopy, fluorescence microscopy and atomic force microscopy (AFM), the temperature and pressure dependent phase behavior of the five-component anionic model raft lipid mixture DOPC/DOPG/DPPC/DPPG/cholesterol (20:5:45:5:25 mol%) was investigated. A temperature range from 5 to 65 °C and a pressure range up to 16 kbar were covered to establish the temperature-pressure phase diagram of this heterogeneous model biomembrane system. Incorporation of 10-20 mol% PG still leads to liquid-ordered (l(o))-liquid-disordered (l(d)) phase coexistence regions over a wide range of temperatures and pressures. Compared to the corresponding neutral model raft mixture (DOPC/DPPC/Chol 25:50:25 mol%), the p,T-phase diagram is - as expected and in accordance with the Gibbs phase rule - more complex, the phase sequence as a function of temperature and pressure is largely similar, however. This anionic heterogeneous model membrane system will serve as a more realistic model biomembrane system to study protein interactions with anionic lipid bilayers displaying liquid-disordered/liquid-ordered domain coexistence over a wide range of the temperature-pressure plane, thus allowing also studies of biologically relevant systems encountered under extreme environmental conditions.
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Affiliation(s)
- Shobhna Kapoor
- Physical Chemistry I-Biophysical Chemistry, TU Dortmund University, Dortmund, Germany
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Murgia S, Lampis S, Zucca P, Sanjust E, Monduzzi M. Nucleotide recognition and phosphate linkage hydrolysis at a lipid cubic interface. J Am Chem Soc 2010; 132:16176-84. [PMID: 20977215 DOI: 10.1021/ja1069745] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Mononucleotides, when entrapped within a mono-olein-based cubic Ia3d liquid crystalline phase, have been found to undergo hydrolysis at the sugar-phosphate ester bond in spite of their natural inertness toward hydrolysis. Here, kinetics of the hydrolysis reaction and interactions between the lipid matrix and the mononucleotide adenosine 5'-monophosphate disodium salt (AMP) and its 2'-deoxy derivative (dAMP) are thoroughly investigated in order to shed some light on the mechanism of the nucleotide recognition and phosphate ester hydrolysis. Experiments evidenced that molecular recognition occurs essentially through the sn-2 and the sn-3 alcoholic OH groups of mono-olein. As deduced from the apparent activation energies, the mechanism underlying the hydrolysis reaction is the same for AMP and dAMP. Nevertheless, the reaction proceeds slower for the latter, highlighting a substantial difference in the chemical behavior of the two nucleotides. A model that explains the hydrolysis reaction is presented. Remarkably, the hydrolysis mechanism appears to be highly specific for the Ia3d phase.
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Affiliation(s)
- Sergio Murgia
- Department of Chemical Science, Cagliari University, CNBS and CSGI, ss 554, bivio Sestu, 09042 Monserrato (CA), Italy.
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Pires PAR, El-Seoud OA. Surfactants with an amide group “spacer”: Synthesis of 3-(acylaminopropyl)trimethylammonium chlorides and their aggregation in aqueous solutions. J Colloid Interface Sci 2006; 304:474-85. [PMID: 17046779 DOI: 10.1016/j.jcis.2006.09.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2006] [Revised: 08/10/2006] [Accepted: 09/02/2006] [Indexed: 10/24/2022]
Abstract
The cationic surfactants RCONH(CH2)3N+(CH3)3Cl-, where RCO = C10, C12, C14, and C16, respectively, have been synthesized by reacting the appropriate carboxylic acids with 3-N,N-dimethylamino-1-propylamine, followed by dehydration of the ammonium salt produced. Reaction of the intermediates obtained (RCONH(CH2)3N(CH3)2) with methyl iodide, followed by chloride/iodide ion-exchange furnished the surfactants. Their adsorption and aggregation in aqueous solutions have been studied by surface tension, conductivity, EMF, static light scattering and FTIR. Additional information on the micellar structure was secured from effects of the medium on the 1H NMR chemical shifts and 2D ROESY spectra. Increasing the length of the acyl moiety increased the micelle aggregation number, and decreased the minimum area/surfactant molecule at the solution/air interface, the critical micelle concentration, and the degree of dissociation of the counter-ion. Gibbs free energies of adsorption at the solution/air interface and of micelle formation were calculated, and compared to those of 2-(acylaminoethyl)trimethylammonium chloride; alkyl trimethylammonium chloride; and benzyl(3-acylaminopropyl)dimethylammonium chloride surfactants. For both processes (adsorption and micellization), contributions of the CH2 groups in the hydrophobic tail and of the head-group to DeltaG0 were calculated. The former contribution was found to be similar to those of other cationic surfactants, whereas the latter one is more negative than those of 2-(acylaminoethyl)trimethylammonium chlorides and trimethylammonium chlorides. This is attributed to a combination of increased hydrophobicity of the head-group, and (direct- or water-mediated) intermolecular hydrogen-bonding of aggregated monomers, via the amide group. FTIR and NMR results indicated that the amide group lies at the micellar interface.
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Affiliation(s)
- Paulo A R Pires
- Instituto de Química, Universidade de São Paulo, C.P. 26077, 05513-970, São Paulo, SP, Brazil
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10
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Nicolini C, Kraineva J, Khurana M, Periasamy N, Funari SS, Winter R. Temperature and pressure effects on structural and conformational properties of POPC/SM/cholesterol model raft mixtures--a FT-IR, SAXS, DSC, PPC and Laurdan fluorescence spectroscopy study. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2006; 1758:248-58. [PMID: 16529710 DOI: 10.1016/j.bbamem.2006.01.019] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2005] [Revised: 01/24/2006] [Accepted: 01/26/2006] [Indexed: 11/17/2022]
Abstract
We report on the effects of temperature and pressure on the structure, conformation and phase behavior of aqueous dispersions of the model lipid "raft" mixture palmitoyloleoylphosphatidylcholine (POPC)/bovine brain sphingomyelin (SM)/cholesterol (Chol) (1:1:1). We investigated interchain interactions, hydrogen bonding, conformational and structural properties as well as phase transformations of this system using Fourier transform-infrared (FT-IR) spectroscopy, small-angle X-ray scattering (SAXS), differential scanning calorimetry (DSC) coupled with pressure perturbation calorimetry (PPC), and Laurdan fluorescence spectroscopy. The IR spectral parameters in combination with the scattering patterns from the SAXS measurements were used to detect structural and conformational transformations upon changes of pressure up to 7-9 kbar and temperature in the range from 1 to about 80 degrees C. The generalized polarization function (GP) values, obtained from the Laurdan fluorescence spectroscopy studies also reveal temperature and pressure dependent phase changes. DSC and PPC were used to detect thermodynamic properties accompanying the temperature-dependent phase changes. In combination with literature fluorescence spectroscopy and microscopy data, a tentative p,T stability diagram of the mixture has been established. The data reveal a broad liquid-order/solid-ordered (lo+so) two-phase coexistence region below 8+/-2 degrees C at ambient pressure. With increasing temperature, a lo+ld+so three-phase region is formed, which extends up to approximately 27 degrees C, where a liquid-ordered/liquid-disordered (lo+ld) immiscibility region is formed. Finally, above 48+/-2 degrees C, the POPC/SM/Chol (1:1:1) mixture becomes completely fluid-like (liquid-disordered, ld). With increasing pressure, all phase transition lines shift to higher temperatures. Notably, the lo+ld (+so) phase coexistence region, mimicking raft-like lateral phase separation in natural membranes, extends over a rather wide temperature range of about 40 degrees C, and a pressure range, which extends up to about 2 kbar for T=37 degrees C. Interestingly, in this pressure range, ceasing of membrane protein function in natural membrane environments has been observed for a variety of systems.
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Affiliation(s)
- Chiara Nicolini
- University of Dortmund, Department of Chemistry, Physical Chemistry I-Biophysical Chemistry, Otto-Hahn-Strasse 6, D-44227 Dortmund, Germany
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Ganem-Quintanar A, Quintanar-Guerrero D, Buri P. Monoolein: a review of the pharmaceutical applications. Drug Dev Ind Pharm 2000; 26:809-20. [PMID: 10900537 DOI: 10.1081/ddc-100101304] [Citation(s) in RCA: 152] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- A Ganem-Quintanar
- Universidad Nacional Autónoma de México, Cuautitlán Izcalli, Mexico.
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Lesile SB, Puvvada S, Ratna BR, Rudolph AS. Encapsulation of hemoglobin in a bicontinuous cubic phase lipid. BIOCHIMICA ET BIOPHYSICA ACTA 1996; 1285:246-54. [PMID: 8972709 DOI: 10.1016/s0005-2736(96)00169-1] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The effects of encapsulating bovine hemoglobin (BHb) in the bicontinuous cubic phase formed by monooleoylglycerol and water was investigated with Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction. Cubic phase was formed in the presence of 1-10 wt% BHb. Studies using X-ray diffraction reveal that at 0.5-2.5 wt% BHb, the cubic phase structure is characterized by the double diamond lattice (Pn3m). At 2.5-5 wt% BHb, coexistence of two cubic phase structures, Pn3m and the gyroid lattice (Ia3d), was observed while at BHb, concentrations higher than 5 wt% the gyroid structure persists. FTIR shows there is an increase in intensity of the free nu C = O (1745 cm-1) and a corresponding decrease in the intensity of the hydrogen bonded nu C = O (1720 cm-1) as the BHb concentration is increased. The nu C-O-CO peak shifts from 1183 cm-1 to 1181 cm-1 as the concentration of BHb raised from 2.5 to 10 wt% indicating BHb may induce subtle changes in the interfacial region of cubic phase monoolein. The bandwidth of the nu asCH2 stretch (2926 cm-1) increased in the presence of 5 wt% BHb compared to samples with 2.5 or 10 wt% BHb. The increase in frequency of the nu sCH2 stretch (2854 cm-1) induced by increasing temperature 20 to 60 degrees C was dampened when BHb was present compared to samples heated in isotonic buffer. Analysis of the amide I band at 1650 cm-1 showed that the secondary structure of BHb is not affected by encapsulation in monoolein. In vitro release studies showed that 45% of the entrapped BHb was released after 144 h at 37 degrees C. The porous nature of bulk cubic phase was further demonstrated by diffusion of K2Fe(CN)6 and conversion of 73% of the oxyhemoglobin to methemoglobin after 1 h. These results suggest that the cubic phase may be useful for encapsulation of Hb as a red cell substitute and for the encapsulation and delivery of other bioactive agents.
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Affiliation(s)
- S B Lesile
- Center for Biomolecular Science and Engineering, Naval Research Laboratory, Washington, DC 20375-5002, USA
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13
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An FTIR study of the hydration and molecular ordering at phase transitions in the monooleoylglycerol/water system. Chem Phys Lipids 1994. [DOI: 10.1016/0009-3084(94)90065-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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