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Vitkova V, Yordanova V, Staneva G, Petkov O, Stoyanova-Ivanova A, Antonova K, Popkirov G. Dielectric Properties of Phosphatidylcholine Membranes and the Effect of Sugars. MEMBRANES 2021; 11:membranes11110847. [PMID: 34832076 PMCID: PMC8623822 DOI: 10.3390/membranes11110847] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/25/2021] [Accepted: 10/27/2021] [Indexed: 11/16/2022]
Abstract
Simple carbohydrates are associated with the enhanced risk of cardiovascular disease and adverse changes in lipoproteins in the organism. Conversely, sugars are known to exert a stabilizing effect on biological membranes, and this effect is widely exploited in medicine and industry for cryopreservation of tissues and materials. In view of elucidating molecular mechanisms involved in the interaction of mono- and disaccharides with biomimetic lipid systems, we study the alteration of dielectric properties, the degree of hydration, and the rotational order parameter and dipole potential of lipid bilayers in the presence of sugars. Frequency-dependent deformation of cell-size unilamellar lipid vesicles in alternating electric fields and fast Fourier transform electrochemical impedance spectroscopy are applied to measure the specific capacitance of phosphatidylcholine lipid bilayers in sucrose, glucose and fructose aqueous solutions. Alteration of membrane specific capacitance is reported in sucrose solutions, while preservation of membrane dielectric properties is established in the presence of glucose and fructose. We address the effect of sugars on the hydration and the rotational order parameter for 1-palmitoyl-2-oleoyl-sn-glycero-3- phosphocholine (POPC) and 1-stearoyl-2-oleoyl-sn-glycero-3- phosphocholine (SOPC). An increased degree of lipid packing is reported in sucrose solutions. The obtained results provide evidence that some small carbohydrates are able to change membrane dielectric properties, structure, and order related to membrane homeostasis. The reported data are also relevant to future developments based on the response of lipid bilayers to external physical stimuli such as electric fields and temperature changes.
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Affiliation(s)
- Victoria Vitkova
- Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee, Blvd., 1784 Sofia, Bulgaria; (O.P.); (A.S.-I.); (K.A.)
- Correspondence:
| | - Vesela Yordanova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 21, 1113 Sofia, Bulgaria; (V.Y.); (G.S.)
| | - Galya Staneva
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 21, 1113 Sofia, Bulgaria; (V.Y.); (G.S.)
| | - Ognyan Petkov
- Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee, Blvd., 1784 Sofia, Bulgaria; (O.P.); (A.S.-I.); (K.A.)
| | - Angelina Stoyanova-Ivanova
- Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee, Blvd., 1784 Sofia, Bulgaria; (O.P.); (A.S.-I.); (K.A.)
| | - Krassimira Antonova
- Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee, Blvd., 1784 Sofia, Bulgaria; (O.P.); (A.S.-I.); (K.A.)
| | - Georgi Popkirov
- Central Laboratory of Solar Energy and New Energy Sources, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee, Blvd., 1784 Sofia, Bulgaria;
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Gongadze E, Mesarec L, Kralj S, Kralj-Iglič V, Iglič A. On the Role of Electrostatic Repulsion in Topological Defect-Driven Membrane Fission. MEMBRANES 2021; 11:membranes11110812. [PMID: 34832041 PMCID: PMC8619715 DOI: 10.3390/membranes11110812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/16/2021] [Accepted: 10/21/2021] [Indexed: 12/29/2022]
Abstract
Within a modified Langevin Poisson–Boltzmann model of electric double layers, we derived an analytical expression for osmotic pressure between two charged surfaces. The orientational ordering of the water dipoles as well as the space dependencies of electric potentials, electric fields, and osmotic pressure between two charged spheres were taken into account in the model. Thus, we were able to capture the interaction between the parent cell and connected daughter vesicle or the interactions between neighbouring beads in necklace-like membrane protrusions. The predicted repulsion between them can facilitate the topological antidefect-driven fission of membrane daughter vesicles and the fission of beads of undulated membrane protrusions.
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Affiliation(s)
- Ekaterina Gongadze
- Laboratory of Physics, Faculty of Electrical Engineering, University of Ljubljana, 1000 Ljubljana, Slovenia; (E.G.); (L.M.)
| | - Luka Mesarec
- Laboratory of Physics, Faculty of Electrical Engineering, University of Ljubljana, 1000 Ljubljana, Slovenia; (E.G.); (L.M.)
| | - Samo Kralj
- Condensed Matter Physics Department, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia;
- Faculty of Natural Sciences and Mathematics, University of Maribor, Koroška 160, 2000 Maribor, Slovenia
| | - Veronika Kralj-Iglič
- Laboratory of Clinical Biophysics, Faculty of Health Sciences, University of Ljubljana, 1000 Ljubljana, Slovenia;
| | - Aleš Iglič
- Laboratory of Physics, Faculty of Electrical Engineering, University of Ljubljana, 1000 Ljubljana, Slovenia; (E.G.); (L.M.)
- Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
- Correspondence: ; Tel.: +386-1-4768-825
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Raval J, Gongadze E, Benčina M, Junkar I, Rawat N, Mesarec L, Kralj-Iglič V, Góźdź W, Iglič A. Mechanical and Electrical Interaction of Biological Membranes with Nanoparticles and Nanostructured Surfaces. MEMBRANES 2021; 11:membranes11070533. [PMID: 34357183 PMCID: PMC8307671 DOI: 10.3390/membranes11070533] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 07/05/2021] [Accepted: 07/05/2021] [Indexed: 11/27/2022]
Abstract
In this review paper, we theoretically explain the origin of electrostatic interactions between lipid bilayers and charged solid surfaces using a statistical mechanics approach, where the orientational degree of freedom of lipid head groups and the orientational ordering of the water dipoles are considered. Within the modified Langevin Poisson–Boltzmann model of an electric double layer, we derived an analytical expression for the osmotic pressure between the planar zwitterionic lipid bilayer and charged solid planar surface. We also show that the electrostatic interaction between the zwitterionic lipid head groups of the proximal leaflet and the negatively charged solid surface is accompanied with a more perpendicular average orientation of the lipid head-groups. We further highlight the important role of the surfaces’ nanostructured topography in their interactions with biological material. As an example of nanostructured surfaces, we describe the synthesis of TiO2 nanotubular and octahedral surfaces by using the electrochemical anodization method and hydrothermal method, respectively. The physical and chemical properties of these nanostructured surfaces are described in order to elucidate the influence of the surface topography and other physical properties on the behavior of human cells adhered to TiO2 nanostructured surfaces. In the last part of the paper, we theoretically explain the interplay of elastic and adhesive contributions to the adsorption of lipid vesicles on the solid surfaces. We show the numerically predicted shapes of adhered lipid vesicles corresponding to the minimum of the membrane free energy to describe the influence of the vesicle size, bending modulus, and adhesion strength on the adhesion of lipid vesicles on solid charged surfaces.
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Affiliation(s)
- Jeel Raval
- Group of Physical Chemistry of Complex Systems, Institute of Physical Chemistry, Polish Academy of Sciences, 01-224 Warsaw, Poland; (J.R.); (W.G.)
| | - Ekaterina Gongadze
- Laboratory of Physics, Faculty of Electrical Engineering, University of Ljubljana, 1000 Ljubljana, Slovenia; (E.G.); (N.R.); (L.M.)
| | - Metka Benčina
- Department of Surface Engineering and Optoelectronics, Jožef Stefan Institute, 1000 Ljubljana, Slovenia; (M.B.); (I.J.)
| | - Ita Junkar
- Department of Surface Engineering and Optoelectronics, Jožef Stefan Institute, 1000 Ljubljana, Slovenia; (M.B.); (I.J.)
| | - Niharika Rawat
- Laboratory of Physics, Faculty of Electrical Engineering, University of Ljubljana, 1000 Ljubljana, Slovenia; (E.G.); (N.R.); (L.M.)
| | - Luka Mesarec
- Laboratory of Physics, Faculty of Electrical Engineering, University of Ljubljana, 1000 Ljubljana, Slovenia; (E.G.); (N.R.); (L.M.)
| | - Veronika Kralj-Iglič
- Laboratory of Clinical Biophysics, Faculty of Health Sciences, University of Ljubljana, 1000 Ljubljana, Slovenia;
| | - Wojciech Góźdź
- Group of Physical Chemistry of Complex Systems, Institute of Physical Chemistry, Polish Academy of Sciences, 01-224 Warsaw, Poland; (J.R.); (W.G.)
| | - Aleš Iglič
- Laboratory of Physics, Faculty of Electrical Engineering, University of Ljubljana, 1000 Ljubljana, Slovenia; (E.G.); (N.R.); (L.M.)
- Laboratory of Clinical Biophysics, Chair of Orthopaedics, Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
- Correspondence: ; Tel.: +386-1-4768-825
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Water Pores in Planar Lipid Bilayers at Fast and Slow Rise of Transmembrane Voltage. MEMBRANES 2021; 11:membranes11040263. [PMID: 33916447 PMCID: PMC8067013 DOI: 10.3390/membranes11040263] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 03/28/2021] [Accepted: 03/29/2021] [Indexed: 12/12/2022]
Abstract
Basic understanding of the barrier properties of biological membranes can be obtained by studying model systems, such as planar lipid bilayers. Here, we study water pores in planar lipid bilayers in the presence of transmembrane voltage. Planar lipid bilayers were exposed to fast and slow linearly increasing voltage and current signals. We measured the capacitance, breakdown voltage, and rupture time of planar lipid bilayers composed of 1-pamitoyl 2-oleoyl phosphatidylcholine (POPC), 1-pamitoyl 2-oleoyl phosphatidylserine (POPS), and a mixture of both lipids in a 1:1 ratio. Based on the measurements, we evaluated the change in the capacitance of the planar lipid bilayer corresponding to water pores, the radius of water pores at membrane rupture, and the fraction of the area of the planar lipid bilayer occupied by water pores.planar lipid bilayer capacitance, which corresponds to water pores, water pore radius at the membrane rupture, and a fraction of the planar lipid bilayer area occupied by water pores. The estimated pore radii determining the rupture of the planar lipid bilayer upon fast build-up of transmembrane voltage are 0.101 nm, 0.110 nm, and 0.106 nm for membranes composed of POPC, POPS, and POPC:POPS, respectively. The fraction of the surface occupied by water pores at the moment of rupture of the planar lipid bilayer The fraction of an area that is occupied by water pores at the moment of planar lipid bilayer rupture is in the range of 0.1–1.8%.
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Drab M, Gongadze E, Kralj-Iglič V, Iglič A. Electric Double Layer and Orientational Ordering of Water Dipoles in Narrow Channels within a Modified Langevin Poisson-Boltzmann Model. ENTROPY (BASEL, SWITZERLAND) 2020; 22:E1054. [PMID: 33286823 PMCID: PMC7597128 DOI: 10.3390/e22091054] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 09/04/2020] [Accepted: 09/18/2020] [Indexed: 02/05/2023]
Abstract
The electric double layer (EDL) is an important phenomenon that arises in systems where a charged surface comes into contact with an electrolyte solution. In this work we describe the generalization of classic Poisson-Boltzmann (PB) theory for point-like ions by taking into account orientational ordering of water molecules. The modified Langevin Poisson-Boltzmann (LPB) model of EDL is derived by minimizing the corresponding Helmholtz free energy functional, which includes also orientational entropy contribution of water dipoles. The formation of EDL is important in many artificial and biological systems bound by a cylindrical geometry. We therefore numerically solve the modified LPB equation in cylindrical coordinates, determining the spatial dependencies of electric potential, relative permittivity and average orientations of water dipoles within charged tubes of different radii. Results show that for tubes of a large radius, macroscopic (net) volume charge density of coions and counterions is zero at the geometrical axis. This is attributed to effective electrolyte charge screening in the vicinity of the inner charged surface of the tube. For tubes of small radii, the screening region extends into the whole inner space of the tube, leading to non-zero net volume charge density and non-zero orientational ordering of water dipoles near the axis.
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Affiliation(s)
- Mitja Drab
- Faculty of Electrical Engineering, Tržaška Cesta 25, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (M.D.); (E.G.)
| | - Ekaterina Gongadze
- Faculty of Electrical Engineering, Tržaška Cesta 25, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (M.D.); (E.G.)
| | - Veronika Kralj-Iglič
- Faculty of Health Sciences, Zdravstvena Pot 5, University of Ljubljana, SI-1000 Ljubljana, Slovenia;
| | - Aleš Iglič
- Faculty of Electrical Engineering, Tržaška Cesta 25, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (M.D.); (E.G.)
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Kłos J, Lamperski S. Electrical double layer in molten salts taking into account Lennard-Jones potential. Electrochim Acta 2020. [DOI: 10.1016/j.electacta.2020.135747] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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