1
|
de Souza JP, Chow CM, Karnik R, Bazant MZ. Nonlinear ion transport mediated by induced charge in ultrathin nanoporous membranes. Phys Rev E 2021; 104:044802. [PMID: 34781445 DOI: 10.1103/physreve.104.044802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 09/07/2021] [Indexed: 11/07/2022]
Abstract
Ultrathin membranes with nanoporous conduits show promise for ionic separations and desalination applications, but the mechanisms underlying the nonlinear ionic transport observed in these systems are not well understood. Here, we demonstrate how induced charge at membrane interfaces can lead to nonlinear ionic transport and voltage-dependent conductance through such channels. The application of an electric field on a polarizable membrane leads to induced charges at the membrane interfaces. The induced charges in turn are screened by diffuse charges in the electrolyte, which are acted upon by the electric field. For extremely thin membranes, the induced charge effect can be significant even for moderate applied voltages commonly used in experiments. We apply a continuum Poisson-Nernst-Planck model to characterize the current-voltage behavior of ultrathin membranes over a wide parameter space. The predictions of the model are compared to recent experiments on graphene and MoS_{2} membranes in an electric field. We expect the role of induced charge to be especially pronounced in the limit of atomically thin membranes.
Collapse
Affiliation(s)
- J Pedro de Souza
- Department of Chemical Engineering, Massachusetts Institute of Technology, 25 Ames St., Cambridge, Massachusetts 02142, USA
| | - Chun-Man Chow
- Department of Chemical Engineering, Massachusetts Institute of Technology, 25 Ames St., Cambridge, Massachusetts 02142, USA
| | - Rohit Karnik
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139, USA
| | - Martin Z Bazant
- Department of Chemical Engineering, Massachusetts Institute of Technology, 25 Ames St., Cambridge, Massachusetts 02142, USA.,Department of Mathematics, Massachusetts Institute of Technology, 182 Memorial Drive, Cambridge, Massachusetts 02142, USA
| |
Collapse
|
2
|
Prathyusha KR, Pagonabarraga I, Kumar PBS. Modification of lipid membrane compressibility induced by an electric field. Phys Rev E 2021; 102:062413. [PMID: 33466026 DOI: 10.1103/physreve.102.062413] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 10/20/2020] [Indexed: 11/07/2022]
Abstract
Changes in membrane deformation and compressibility, induced by an external electric field, are investigated using coarse-grained martini force field simulations in a salt-free environment. We observe changes in the area of the membrane above a critical electric field. Below this value, the membrane compressibility modulus is found to decrease monotonically. For higher electric fields, the membrane projected area remains constant while the net interfacial area increases, with the corresponding compressibility moduli, show the opposite behavior. We find that the mechanical parameters, surface tension and bending modulus, of a freely floating membrane in the absence of explicit ions, are unaffected by the presence of the electric field. We believe these results have a bearing on our understanding of the electroformation of uncharged lipids in a salt-free environment.
Collapse
Affiliation(s)
- K R Prathyusha
- Department of Physics, Indian Institute of Technology Madras, Chennai, India
| | - Ignacio Pagonabarraga
- CECAM, Centre Européen de Calcul Atomique et Moléculaire, École Polytechnique Fédérale de Laussane (EPFL), Batochime, Avenue Forel 2, 1015 Lausanne, Switzerland.,Departament de Física de la Matèria Condensada, Universitat de Barcelona, C. Martí Franquès 1, 08028 8 Barcelona, Spain.,University of Barcelona Institute of Complex Systems (UBICS), Universitat de Barcelona, 08028 10 Barcelona, Spain
| | - P B Sunil Kumar
- Department of Physics, Indian Institute of Technology Madras, Chennai, India.,Indian Institute of Technology Palakkad, Ahalia Integrated Campus, Kozhippara, Palakkad - 678557, Kerala, India
| |
Collapse
|
3
|
Perrier DL, Rems L, Boukany PE. Lipid vesicles in pulsed electric fields: Fundamental principles of the membrane response and its biomedical applications. Adv Colloid Interface Sci 2017; 249:248-271. [PMID: 28499600 DOI: 10.1016/j.cis.2017.04.016] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 04/24/2017] [Accepted: 04/25/2017] [Indexed: 01/04/2023]
Abstract
The present review focuses on the effects of pulsed electric fields on lipid vesicles ranging from giant unilamellar vesicles (GUVs) to small unilamellar vesicles (SUVs), from both fundamental and applicative perspectives. Lipid vesicles are the most popular model membrane systems for studying biophysical and biological processes in living cells. Furthermore, as vesicles are made from biocompatible and biodegradable materials, they provide a strategy to create safe and functionalized drug delivery systems in health-care applications. Exposure of lipid vesicles to pulsed electric fields is a common physical method to transiently increase the permeability of the lipid membrane. This method, termed electroporation, has shown many advantages for delivering exogenous molecules including drugs and genetic material into vesicles and living cells. In addition, electroporation can be applied to induce fusion between vesicles and/or cells. First, we discuss in detail how research on cell-size GUVs as model cell systems has provided novel insight into the basic mechanisms of cell electroporation and associated phenomena. Afterwards, we continue with a thorough overview how electroporation and electrofusion have been used as versatile methods to manipulate vesicles of all sizes in different biomedical applications. We conclude by summarizing the open questions in the field of electroporation and possible future directions for vesicles in the biomedical field.
Collapse
|
4
|
|
5
|
Hemmerle A, Fragneto G, Daillant J, Charitat T. Reduction in Tension and Stiffening of Lipid Membranes in an Electric Field Revealed by X-Ray Scattering. PHYSICAL REVIEW LETTERS 2016; 116:228101. [PMID: 27314739 DOI: 10.1103/physrevlett.116.228101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Indexed: 06/06/2023]
Abstract
The effect of ac electric fields on the elasticity of supported lipid bilayers is investigated at the microscopic level using grazing incidence synchrotron x-ray scattering. A strong decrease in the membrane tension up to 1 mN/m and a dramatic increase of its effective rigidity up to 300 k_{B}T are observed for local electric potentials seen by the membrane ≲1 V. The experimental results are analyzed using detailed electrokinetic modeling and nonlinear Poisson-Boltzmann theory. Based on a modeling of the electromagnetic stress, which provides an accurate description of the bilayer separation versus pressure curves, we show that the decrease in tension results from the amplification of charge fluctuations on the membrane surface whereas the increase in bending rigidity results from the direct interaction between charges in the electric double layer. These effects eventually lead to a destabilization of the bilayer and vesicle formation. Similar effects are expected at the tens of nanometers length scale in cell membranes with lower tension, and could explain a number of electrically driven processes.
Collapse
Affiliation(s)
- Arnaud Hemmerle
- UPR 22/CNRS, Institut Charles Sadron, Université de Strasbourg, 23 rue du Loess, BP 84047 67034 Strasbourg Cedex 2, France
| | - Giovanna Fragneto
- Institut Laue-Langevin, 71 avenue des Martyrs, BP 156, 38042 Grenoble Cedex, France
| | - Jean Daillant
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, BP 48, F-91192 Gif-sur-Yvette Cedex, France
| | - Thierry Charitat
- UPR 22/CNRS, Institut Charles Sadron, Université de Strasbourg, 23 rue du Loess, BP 84047 67034 Strasbourg Cedex 2, France
| |
Collapse
|
6
|
Impacts of electrical parameters on the electroformation of giant vesicles on ITO glass chips. Colloids Surf B Biointerfaces 2016; 140:560-566. [DOI: 10.1016/j.colsurfb.2015.11.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 11/06/2015] [Accepted: 11/10/2015] [Indexed: 11/20/2022]
|
7
|
Hoiles W, Krishnamurthy V, Cornell B. Modelling the Bioelectronic Interface in Engineered Tethered Membranes: From Biosensing to Electroporation. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2015; 9:321-333. [PMID: 25373111 DOI: 10.1109/tbcas.2014.2357420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This paper studies the construction and predictive models of three novel measurement platforms: (i) a Pore Formation Measurement Platform (PFMP) for detecting the presence of pore forming proteins and peptides, (ii) the Ion Channel Switch (ICS) biosensor for detecting the presence of analyte molecules in a fluid chamber, and (iii) an Electroporation Measurement Platform (EMP) that provides reliable measurements of the electroporation phenomenon. Common to all three measurement platforms is that they are comprised of an engineered tethered membrane that is formed via a rapid solvent exchange technique allowing the platform to have a lifetime of several months. The membrane is tethered to a gold electrode bioelectronic interface that includes an ionic reservoir separating the membrane and gold surface, allowing the membrane to mimic the physiological response of natural cell membranes. The electrical response of the PFMP, ICS, and EMP are predicted using continuum theories for electrodiffusive flow coupled with boundary conditions for modelling chemical reactions and electrical double layers present at the bioelectronic interface. Experimental measurements are used to validate the predictive accuracy of the dynamic models. These include using the PFMP for measuring the pore formation dynamics of the antimicrobial peptide PGLa and the protein toxin Staphylococcal α-Hemolysin; the ICS biosensor for measuring nano-molar concentrations of streptavidin, ferritin, thyroid stimulating hormone (TSH), and human chorionic gonadotropin (pregnancy hormone hCG); and the EMP for measuring electroporation of membranes with different tethering densities, and membrane compositions.
Collapse
|
8
|
Hoiles W, Krishnamurthy V, Cranfield CG, Cornell B. An engineered membrane to measure electroporation: effect of tethers and bioelectronic interface. Biophys J 2015; 107:1339-51. [PMID: 25229142 DOI: 10.1016/j.bpj.2014.07.056] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 06/27/2014] [Accepted: 07/30/2014] [Indexed: 01/19/2023] Open
Abstract
This article reports on the construction and predictive models for a platform comprised of an engineered tethered membrane. The platform provides a controllable and physiologically relevant environment for the study of the electroporation process. The mixed self-assembled membrane is formed via a rapid solvent exchange technique. The membrane is tethered to the gold electrode and includes an ionic reservoir separating the membrane and gold surface. Above the membrane, there is an electrolyte solution, and a gold counterelectrode. A voltage is applied between the gold electrodes and the current measured. The current is dependent on the energy required to form aqueous pores and the conductance of each pore. A two-level predictive model, consisting of a macroscopic and a continuum model, is developed to relate the pore dynamics to the measured current. The macroscopic model consists of an equivalent circuit model of the tethered membrane, and asymptotic approximations to the Smoluchowski-Einstein equation of electroporation that is dependent on the pore conductance and the energy required to form aqueous pores. The continuum model is a generalized Poisson-Nernst-Planck (GPNP) system where an activity coefficient to account for steric effects of ions is added to the standard PNP system. The GPNP is used to evaluate the conductance of aqueous pores, and the electrical energy required to form the pores. As an outcome of the setup of the device and the two-level model, biologically important variables can be estimated from experimental measurements. To validate the accuracy of the two-level model, the predicted current is compared with experimentally measured current for different tethering densities.
Collapse
Affiliation(s)
- William Hoiles
- Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, British Columbia, Canada
| | - Vikram Krishnamurthy
- Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, British Columbia, Canada.
| | - Charles G Cranfield
- School of Medical and Molecular Biosciences, University of Technology Sydney, Broadway, New South Wales, Australia; Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | - Bruce Cornell
- Surgical Diagnostics, Roseville, New South Wales, Australia
| |
Collapse
|
9
|
Dey M, Bandyopadhyay D, Sharma A, Qian S, Joo SW. Charge Leakage Mediated Pattern Miniaturization in the Electric Field Induced Instabilities of an Elastic Membrane. Ind Eng Chem Res 2014. [DOI: 10.1021/ie500378k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Mohar Dey
- School
of Mechanical Engineering, Yeungnam University, Gyeongsan 712749, South Korea
| | - Dipankar Bandyopadhyay
- Department
of Chemical Engineering, Indian Institute of Technology Guwahati, 781039, Assam, India
- Centre
for Nanotechnology, Indian Institute of Technology Guwahati, 781039, Assam, India
| | - Ashutosh Sharma
- Department
of Chemical Engineering, Indian Institute of Technology Kanpur, UP 208016, India
| | - Shizhi Qian
- Department
of Mechanical and Aerospace Engineering, Old Dominion University, Norfolk, Virginia 23529, United States
| | - Sang Woo Joo
- School
of Mechanical Engineering, Yeungnam University, Gyeongsan 712749, South Korea
| |
Collapse
|
10
|
Gambhire P, Thaokar R. Electrokinetic model for electric-field-induced interfacial instabilities. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 89:032409. [PMID: 24730854 DOI: 10.1103/physreve.89.032409] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Indexed: 06/03/2023]
Abstract
Technology based on electric-field-induced instabilities on thin polymer film surfaces has emerged as a promising candidate for soft lithography. Typically, the instability is modeled using the perfect dielectric (PD) or the leaky dielectric (LD) model. These assume the electric diffuse layer to be infinitesimally large or small, respectively. In the present work we conduct stability analysis assuming a PD-electrolyte solution interface. The concentration of ions and, hence, the diffuse layer thickness is in general assumed to be of the same order as the electrolyte film thickness. The PD-LD models are then realized as limiting cases of the ratio of the double layer thickness to the film thickness.
Collapse
Affiliation(s)
- Priya Gambhire
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai 400 076, India
| | - Rochish Thaokar
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai 400 076, India
| |
Collapse
|
11
|
Loubet B, Hansen PL, Lomholt MA. Electromechanics of a membrane with spatially distributed fixed charges: flexoelectricity and elastic parameters. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 88:062715. [PMID: 24483494 DOI: 10.1103/physreve.88.062715] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Indexed: 06/03/2023]
Abstract
We investigate the electrostatic contribution to the lipid membrane mechanical parameters: tension, bending rigidity, spontaneous curvature, and flexocoefficient, using an approach where stress in the membrane is explicitly balanced. Our model includes an applied electrostatic potential as well as a charge distribution in the membrane. We apply our theory to membranes having surface charges and electric dipoles at the surface.
Collapse
Affiliation(s)
- Bastien Loubet
- MEMPHYS - Center for Biomembrane Physics, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| | - Per Lyngs Hansen
- MEMPHYS - Center for Biomembrane Physics, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| | - Michael Andersen Lomholt
- MEMPHYS - Center for Biomembrane Physics, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| |
Collapse
|
12
|
Seiwert J, Vlahovska PM. Instability of a fluctuating membrane driven by an ac electric field. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 87:022713. [PMID: 23496554 DOI: 10.1103/physreve.87.022713] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 12/04/2012] [Indexed: 06/01/2023]
Abstract
Shape fluctuations of a planar lipid membrane in an ac electric field are investigated using a zero-thickness electromechanical model, which accounts for membrane conductivity and capacitance, and asymmetry in the properties of the fluids separated by the membrane. A linear stability analysis shows that unlike in the case of a dc electric field, a purely capacitive membrane can be destabilized in an ac electric field. The theory highlights that the instability originates from electric pressure exerted on the membrane.
Collapse
Affiliation(s)
- Jacopo Seiwert
- Institut de Physique de Rennes UMR 6251, Université de Rennes, 35042 Rennes, France
| | | |
Collapse
|
13
|
Dey M, Bandyopadhyay D, Sharma A, Qian S, Joo SW. Electric-field-induced interfacial instabilities of a soft elastic membrane confined between viscous layers. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2012; 86:041602. [PMID: 23214594 DOI: 10.1103/physreve.86.041602] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Indexed: 06/01/2023]
Abstract
We explore the electric-field-induced interfacial instabilities of a trilayer composed of a thin elastic film confined between two viscous layers. A linear stability analysis (LSA) is performed to uncover the growth rate and length scale of the different unstable modes. Application of a normal external electric field on such a configuration can deform the two coupled elastic-viscous interfaces either by an in-phase bending or an antiphase squeezing mode. The bending mode has a long-wave nature, and is present even at a vanishingly small destabilizing field. In contrast, the squeezing mode has finite wave-number characteristics and originates only beyond a threshold strength of the electric field. This is in contrast to the instabilities of the viscous films with multiple interfaces where both modes are found to possess long-wave characteristics. The elastic film is unstable by bending mode when the stabilizing forces due to the in-plane curvature and the elastic stiffness are strong and the destabilizing electric field is relatively weak. In comparison, as the electric field increases, a subdominant squeezing mode can also appear beyond a threshold destabilizing field. A dominant squeezing mode is observed when the destabilizing field is significantly strong and the elastic films are relatively softer with lower elastic modulus. In the absence of liquid layers, a free elastic film is also found to be unstable by long-wave bending and finite wave-number squeezing modes. The LSA asymptotically recovers the results obtained by the previous formulations where the membrane bending elasticity is approximately incorporated as a correction term in the normal stress boundary condition. Interestingly, the presence of a very weak stabilizing influence due to a smaller interfacial tension at the elastic-viscous interfaces opens up the possibility of fabricating submicron patterns exploiting the instabilities of a trilayer.
Collapse
Affiliation(s)
- Mohar Dey
- School of Mechanical Engineering, Yeungnam University, Gyeongsan 712-749, South Korea
| | | | | | | | | |
Collapse
|
14
|
Biesheuvel PM, Fu Y, Bazant MZ. Diffuse charge and Faradaic reactions in porous electrodes. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 83:061507. [PMID: 21797372 DOI: 10.1103/physreve.83.061507] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2011] [Revised: 03/19/2011] [Indexed: 05/07/2023]
Abstract
Porous electrodes instead of flat electrodes are widely used in electrochemical systems to boost storage capacities for ions and electrons, to improve the transport of mass and charge, and to enhance reaction rates. Existing porous electrode theories make a number of simplifying assumptions: (i) The charge-transfer rate is assumed to depend only on the local electrostatic potential difference between the electrode matrix and the pore solution, without considering the structure of the double layer (DL) formed in between; (ii) the charge-transfer rate is generally equated with the salt-transfer rate not only at the nanoscale of the matrix-pore interface, but also at the macroscopic scale of transport through the electrode pores. In this paper, we extend porous electrode theory by including the generalized Frumkin-Butler-Volmer model of Faradaic reaction kinetics, which postulates charge transfer across the molecular Stern layer located in between the electron-conducting matrix phase and the plane of closest approach for the ions in the diffuse part of the DL. This is an elegant and purely local description of the charge-transfer rate, which self-consistently determines the surface charge and does not require consideration of reference electrodes or comparison with a global equilibrium. For the description of the DLs, we consider the two natural limits: (i) the classical Gouy-Chapman-Stern model for thin DLs compared to the macroscopic pore dimensions, e.g., for high-porosity metallic foams (macropores >50 nm) and (ii) a modified Donnan model for strongly overlapping DLs, e.g., for porous activated carbon particles (micropores <2 nm). Our theory is valid for electrolytes where both ions are mobile, and it accounts for voltage and concentration differences not only on the macroscopic scale of the full electrode, but also on the local scale of the DL. The model is simple enough to allow us to derive analytical approximations for the steady-state and early transients. We also present numerical solutions to validate the analysis and to illustrate the evolution of ion densities, pore potential, surface charge, and reaction rates in response to an applied voltage.
Collapse
Affiliation(s)
- P M Biesheuvel
- Department of Environmental Technology, Wageningen University, Wageningen, The Netherlands
| | | | | |
Collapse
|
15
|
Vlahovska PM. Nonequilibrium Dynamics of Lipid Membranes: Deformation and Stability in Electric Fields. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/b978-0-12-381266-7.00005-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
|