1
|
Delance L, Santanach-Carreras E, Passade-Boupat N, Lequeux F, Talini L, Verneuil E. How emulsified droplets induce the bursting of suspended films of liquid mixtures. SOFT MATTER 2024; 20:5407-5416. [PMID: 38941082 DOI: 10.1039/d4sm00240g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/29/2024]
Abstract
Emulsion droplets of silicone oil (PDMS) are widely used as antifoaming agents but, in the case of non-aqueous foams, the mechanisms responsible for the bursting of the films separating the bubbles remain unclear. We consider a ternary non-aqueous liquid mixture in which PDMS-rich microdroplets are formed by spontaneous emulsification. In order to quantitatively assess the effect of the emulsified microdroplets, we measure the lifetime of sub-micrometer-thick suspended films of these emulsions as well as the time variations of their thickness profiles. We observe that a droplet entering the film reduces its lifetime by inducing a local and fast thinning. In most cases, we ascribe it to the spreading of the drop at one of the film interfaces with air, which drags the underlying liquid and eventually causes the film to burst rapidly. We explain why, despite slower spreading, more viscous droplets cause films to burst more efficiently. More rarely, microdroplets may bridge the two interfaces of the film, resulting in an even more efficient bursting of the film, which we explain.
Collapse
Affiliation(s)
- Léa Delance
- Soft Matter Sciences and Engineering (SIMM), ESPCI Paris, PSL University, Sorbonne Université, CNRS, F-75005 Paris, France.
- Laboratoire Physico-Chimie des Interfaces Complexes, ESPCI Paris, 10 rue Vauquelin, F-75231 Paris, France
- TOTALEnergies S.A., Pôle d'Etudes et de Recherches de Lacq, BP 47, 64170 Lacq, France
| | - Enric Santanach-Carreras
- TOTALEnergies S.A., Pôle d'Etudes et de Recherches de Lacq, BP 47, 64170 Lacq, France
- Laboratoire Physico-Chimie des Interfaces Complexes, Chemstartup, RD 817, 64170 Lacq, France
| | - Nicolas Passade-Boupat
- TOTALEnergies S.A., Pôle d'Etudes et de Recherches de Lacq, BP 47, 64170 Lacq, France
- Laboratoire Physico-Chimie des Interfaces Complexes, Chemstartup, RD 817, 64170 Lacq, France
| | - François Lequeux
- Soft Matter Sciences and Engineering (SIMM), ESPCI Paris, PSL University, Sorbonne Université, CNRS, F-75005 Paris, France.
- Laboratoire Physico-Chimie des Interfaces Complexes, ESPCI Paris, 10 rue Vauquelin, F-75231 Paris, France
| | - Laurence Talini
- CNRS, Surface du Verre et Interfaces, Saint-Gobain, 93300 Aubervilliers, France.
| | - Emilie Verneuil
- Soft Matter Sciences and Engineering (SIMM), ESPCI Paris, PSL University, Sorbonne Université, CNRS, F-75005 Paris, France.
- Laboratoire Physico-Chimie des Interfaces Complexes, ESPCI Paris, 10 rue Vauquelin, F-75231 Paris, France
| |
Collapse
|
2
|
Xu C, Zhang Y, Sharma V. Spatiotemporal mapping of nanotopography and thickness transitions of ultrathin foam films. SOFT MATTER 2024; 20:3719-3727. [PMID: 38654634 DOI: 10.1039/d4sm00048j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Freshly formed soap films, soap bubbles, or foam films display iridescent colors due to thin film interference that changes as squeeze flow drives drainage and a progressive decrease in film thickness. Ultrathin (thickness <100 nm) freestanding films of soft matter containing micelles, particles, polyelectrolyte-surfactant complexes, or other supramolecular structures or liquid crystalline phases display drainage via stratification. A fascinating array of thickness variations and transitions, including stepwise thinning and coexistence of thick-thin flat regions, arise in micellar foam films that undergo drainage via stratification. In this tutorial, we describe the IDIOM (interferometry digital imaging optical microscopy) protocols that combine the conventional interferometry principle with digital filtration and image analysis to obtain nanometer accuracy for thickness determination while having high spatial and temporal resolution. We provide fully executable image analysis codes and algorithms for the analysis of nanotopography and summarize some of the unique insights obtained for stratified micellar foam films.
Collapse
Affiliation(s)
- Chenxian Xu
- Department of Chemical Engineering, University of Illinois Chicago, Chicago, IL, USA.
| | - Yiran Zhang
- Department of Chemical Engineering, University of Illinois Chicago, Chicago, IL, USA.
| | - Vivek Sharma
- Department of Chemical Engineering, University of Illinois Chicago, Chicago, IL, USA.
| |
Collapse
|
3
|
Appleby BA, Chacon A, Mishra A, Liserre M, Goggin DM, Samaniuk JR. Subphase Exchange Cell for Studying Fluid-Fluid Interfaces with Optical Microscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:2174-2182. [PMID: 38226897 DOI: 10.1021/acs.langmuir.3c03154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2024]
Abstract
A subphase exchange cell was designed to observe fluid-fluid interfaces with a conventional optical microscope while simultaneously changing the subphase chemistry. Materials including phospholipids, asphaltenes, and nanoparticles at fluid-fluid interfaces exhibit unique morphological changes as a function of the bulk-phase chemistry. These changes can affect their interfacial material properties and, ultimately, the emergent bulk material properties of the films, foams, and emulsions produced from such interfacial systems. In this work, we combine experiments, computational fluid dynamics simulations, and modeling to establish the operating parameters for a subphase exchange cell of this type to reach a desired concentration. We used the experimental setup to investigate changes to a graphene film during a common wet-etching transfer process. Observations reveal that capillary interactions can induce defects and deformations in the graphene film during the wet-etching process, an important finding that must be considered for any wet-etching transfer technique for 2D materials. More generally, conventional optical microscopy was shown to be able to image the dynamics of interfacial systems during a bulk-phase chemistry change. Potential applications for this equipment and technique include observing morphological dynamics of phospholipid film structure with subphase salinity, asphaltene film structure with subphase pH, and particle film synthesis with subphase chemistry.
Collapse
Affiliation(s)
- Benjamin A Appleby
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Amy Chacon
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Arpit Mishra
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Matteo Liserre
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - David M Goggin
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Joseph R Samaniuk
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| |
Collapse
|
4
|
Lee Y, Park S, Yuan F, Hayden CC, Wang L, Lafer EM, Choi SQ, Stachowiak JC. Transmembrane coupling of liquid-like protein condensates. Nat Commun 2023; 14:8015. [PMID: 38049424 PMCID: PMC10696066 DOI: 10.1038/s41467-023-43332-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 11/06/2023] [Indexed: 12/06/2023] Open
Abstract
Liquid-liquid phase separation of proteins occurs on both surfaces of cellular membranes during diverse physiological processes. In vitro reconstitution could provide insight into the mechanisms underlying these events. However, most existing reconstitution techniques provide access to only one membrane surface, making it difficult to probe transmembrane phenomena. To study protein phase separation simultaneously on both membrane surfaces, we developed an array of freestanding planar lipid membranes. Interestingly, we observed that liquid-like protein condensates on one side of the membrane colocalized with those on the other side, resulting in transmembrane coupling. Our results, based on lipid probe partitioning and mobility of lipids, suggest that protein condensates locally reorganize membrane lipids, a process which could be explained by multiple effects. These findings suggest a mechanism by which signals originating on one side of a biological membrane, triggered by protein phase separation, can be transferred to the opposite side.
Collapse
Affiliation(s)
- Yohan Lee
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Sujin Park
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Feng Yuan
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Carl C Hayden
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Liping Wang
- Department of Biochemistry and Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Eileen M Lafer
- Department of Biochemistry and Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Siyoung Q Choi
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Jeanne C Stachowiak
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA.
- Department of Chemical Engineering, The University of Texas at Austin, Austin, TX, USA.
| |
Collapse
|
5
|
Zabala-Ferrera O, Beltramo PJ. Effects of Ion Concentration and Headgroup Chemistry on Thin Lipid Film Drainage. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:16294-16302. [PMID: 37939040 DOI: 10.1021/acs.langmuir.3c01795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
While the use of lipid nanoparticles in drug delivery applications has grown over the past few decades, much work remains to be done toward the characterization and rational design of the drug carriers. A key feature of delivery is the interaction of the exterior leaflet of the LNP with the outer leaflet of the cell membrane, which relies in part on the fusogenicity of the lipids and the ionic environment. In this paper, we study the interactions between two lipid monolayers using a thin film balance to create lipid thin films and interferometry to measure film evolution. We probe the role of lipid headgroup chemistry and charge, along with ionic solution conditions, in either promoting or hindering film drainage and stability. Specific headgroups phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), and phosphatidylserine (PS) are chosen to represent a combination of charge and fusogenicity. We quantify each film's drainage characteristics over a range of capillary numbers. Qualitatively, we find that films transition from drainage via a large dimple to drainage via channels and vortices as the capillary number increases. Additionally, we observe a transition from electrostatically dominated film drainage at low CaCl2 concentrations to fusogenic-dominated film drainage at higher CaCl2 concentrations for anionic fusogenic (PS) films. Understanding the role of headgroup composition, ionic composition, and ionic concentration will pave the way for the design of tunable vesicle and buffer systems that behave desirably across a range of ex vivo and in vivo environments.
Collapse
Affiliation(s)
- Oscar Zabala-Ferrera
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Peter J Beltramo
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| |
Collapse
|
6
|
Liu P, Beltramo PJ. Effects of crowding on the diffusivity of membrane adhered particles. SOFT MATTER 2023; 19:7708-7716. [PMID: 37791427 DOI: 10.1039/d3sm01269g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
The lateral diffusion of cell membrane inclusions, such as integral membrane proteins and bound receptors, drives critical biological processes, including the formation of complexes, cell-cell signaling, and membrane trafficking. These diffusive processes are complicated by how concentrated, or "crowded", the inclusions are, which can occupy between 30-50% of the area fraction of the membrane. In this work, we elucidate the effects of increasing concentration of model membrane inclusions in a free-standing artificial cell membrane on inclusion diffusivity and the apparent viscosity of the membrane. By multiple particle tracking of fluorescent microparticles covalently tethered to the bilayer, we show the transition from expected Brownian dynamics, which accurately measure the membrane viscosity, to subdiffusive behavior with decreased diffusion coefficient as the particle area fraction increases from 1% to around 30%, approaching physiological levels of crowding. At high crowding, the onset of non-Gaussian behavior is observed. Using hydrodynamic models relating the 2D diffusion coefficient to the viscosity of a membrane, we determine the apparent viscosity of the bilayer from the particle diffusivity and show an increase in the apparent membrane viscosity with increasing particle area fraction. However, the scaling of this increase is in contrast with the behavior of monolayer inclusion diffusion and bulk suspension rheology. These results demonstrate that physiological levels of model membrane crowding nontrivially alter the dynamics and apparent viscosity of the system, which has implications for understanding membrane protein interactions and particle-membrane transport processes.
Collapse
Affiliation(s)
- Paige Liu
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, MA 01003, USA.
| | - Peter J Beltramo
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, MA 01003, USA.
| |
Collapse
|
7
|
Zamaletdinov MF, Miettinen MS, Lipowsky R. Probing the elastic response of lipid bilayers and nanovesicles to leaflet tensions via volume per lipid. SOFT MATTER 2023; 19:6929-6944. [PMID: 37664906 DOI: 10.1039/d3sm00351e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Biological and biomimetic membranes are based on lipid bilayers, consisting of two monolayers or leaflets. One important but challenging physical parameter of these membranes is their tension. For a long time, this tension was explicitly or implicitly taken to be the bilayer tension, acting on the whole bilayer membrane. More recently, it has been realized that it is useful to decompose the bilayer tension into two leaflet tensions and that these tensions are accessible to molecular dynamics simulations. To divide the bilayer up into two leaflets, it is necessary to introduce a midsurface that defines the spatial extent of the two leaflets. In previous studies, this midsurface was obtained from the density profiles across the bilayer and was then used to compute the molecular area per lipid. Here, we develop an alternative approach based on three-dimensional Voronoi tessellation and molecular volume per lipid. Using this volume-based approach, we determine the reference states with tensionless leaflets as well as the optimal volumes and areas per lipid. The optimal lipid volumes have practically the same value in both leaflets, irrespective of the size and curvature of the nanovesicles, whereas the optimal lipid areas are different for the two leaflets and depend on the vesicle size. In addition, we introduce lateral volume compressibilities to describe the elastic response of the lipid volume to the leaflet tensions. We show that the outer leaflet of a nanovesicle is more densely packed and less compressible than the inner leaflet and that this difference becomes more pronounced for smaller vesicles.
Collapse
Affiliation(s)
- Miftakh F Zamaletdinov
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany.
| | - Markus S Miettinen
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany.
- University of Bergen, Department of Chemistry, 5007 Bergen, Norway
- Computational Biology Unit, Department of Informatics, 5008 Bergen, Norway.
| | - Reinhard Lipowsky
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany.
| |
Collapse
|
8
|
Zabala-Ferrera O, Liu P, Beltramo PJ. Determining the Bending Rigidity of Free-Standing Planar Phospholipid Bilayers. MEMBRANES 2023; 13:129. [PMID: 36837632 PMCID: PMC9959114 DOI: 10.3390/membranes13020129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/14/2023] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
We describe a method to determine membrane bending rigidity from capacitance measurements on large area, free-standing, planar, biomembranes. The bending rigidity of lipid membranes is an important biological mechanical property that is commonly optically measured in vesicles, but difficult to quantify in a planar, unsupported system. To accomplish this, we simultaneously image and apply an electric potential to free-standing, millimeter area, planar lipid bilayers composed of DOPC and DOPG phospholipids to measure the membrane Young's (elasticity) modulus. The bilayer is then modeled as two adjacent thin elastic films to calculate bending rigidity from the electromechanical response of the membrane to the applied field. Using DOPC, we show that bending rigidities determined by this approach are in good agreement with the existing work using neutron spin echo on vesicles, atomic force spectroscopy on supported lipid bilayers, and micropipette aspiration of giant unilamellar vesicles. We study the effect of asymmetric calcium concentration on symmetric DOPC and DOPG membranes and quantify the resulting changes in bending rigidity. This platform offers the ability to create planar bilayers of controlled lipid composition and aqueous ionic environment, with the ability to asymmetrically alter both. We aim to leverage this high degree of compositional and environmental control, along with the capacity to measure physical properties, in the study of various biological processes in the future.
Collapse
|
9
|
Mikhailovskaya A, Chatzigiannakis E, Renggli D, Vermant J, Monteux C. From Individual Liquid Films to Macroscopic Foam Dynamics: A Comparison between Polymers and a Nonionic Surfactant. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:10768-10780. [PMID: 35998760 PMCID: PMC9454262 DOI: 10.1021/acs.langmuir.2c00900] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 08/12/2022] [Indexed: 06/15/2023]
Abstract
Foams can resist destabilizaton in ways that appear similar on a macroscopic scale, but the microscopic origins of the stability and the loss thereof can be quite diverse. Here, we compare both the macroscopic drainage and ultimate collapse of aqueous foams stabilized by either a partially hydrolyzed poly(vinyl alcohol) (PVA) or a nonionic low-molecular-weight surfactant (BrijO10) with the dynamics of individual thin films at the microscale. From this comparison, we gain significant insight regarding the effect of both surface stresses and intermolecular forces on macroscopic foam stability. Distinct regimes in the lifetime of the foams were observed. Drainage at early stages is controlled by the different stress-boundary conditions at the surfaces of the bubbles between the polymer and the surfactant. The stress-carrying capacity of PVA-stabilized interfaces is a result of the mutual contribution of Marangoni stresses and surface shear viscosity. In contrast, surface shear inviscidity and much weaker Marangoni stresses were observed for the nonionic surfactant surfaces, resulting in faster drainage times, both at the level of the single film and the macroscopic foam. At longer times, the PVA foams present a regime of homogeneous coalescence where isolated coalescence events are observed. This regime, which is observed only for PVA foams, occurs when the capillary pressure reaches the maximum disjoining pressure. A final regime is then observed for both systems where a fast coalescence front propagates from the top to the bottom of the foams. The critical liquid fractions and capillary pressures at which this regime is obtained are similar for both PVA and BrijO10 foams, which most likely indicates that collapse is related to a universal mechanism that seems unrelated to the stabilizer interfacial dynamics.
Collapse
Affiliation(s)
- Alesya Mikhailovskaya
- Soft
Matter Science and Engineering, ESPCI Paris, CNRS, PSL University, Sorbonne University, 75005 Paris, Franceand
- Institut
de Chimie et des Matériaux Paris-Est, CNRS UMR 7182, 2-8 rue Henri Dunant, 94320 Thiais, France
| | - Emmanouil Chatzigiannakis
- Department
of Materials, ETH Zürich, Vladimir Prelog Weg 5, 8032 Zürich, Switzerland and
- Polymer
Technology Group, Eindhoven University of
Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands
| | - Damian Renggli
- Department
of Materials, ETH Zürich, Vladimir Prelog Weg 5, 8032 Zürich, Switzerland and
| | - Jan Vermant
- Department
of Materials, ETH Zürich, Vladimir Prelog Weg 5, 8032 Zürich, Switzerland and
| | - Cécile Monteux
- Soft Matter
Science and Engineering, ESPCI Paris, CNRS,
PSL University, Sorbonne University, 75005 Paris, France
| |
Collapse
|
10
|
Scheidegger L, Stricker L, Beltramo PJ, Vermant J. Domain Size Regulation in Phospholipid Model Membranes Using Oil Molecules and Hybrid Lipids. J Phys Chem B 2022; 126:5842-5854. [PMID: 35895895 PMCID: PMC9377339 DOI: 10.1021/acs.jpcb.2c02862] [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
The formation of domains in multicomponent lipid mixtures has been suggested to play a role in moderating signal transduction in cells. Understanding how domain size may be regulated by both hybrid lipid molecules and impurities is important for understanding real biological processes; at the same time, developing model systems where domain size can be regulated is crucial to enable systematic studies of domain formation kinetics and thermodynamics. Here, we perform a model study of the effects of oil molecules, which swell the bilayer, and line-active hybrid phospholipids using a thermally induced liquid-solid phase separation in planar, free-standing lipid bilayers consisting of DOPC and DPPC (1,2-dioleoyl-sn-glycero-3-phosphocholine and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine, respectively). The experiments show that the kinetics of domain growth are significantly affected by the type and molecular structure of the oil (squalene, hexadecane, or decane), with the main contributing factors being the degree of swelling of the bilayer and the changes in line tension induced by the different oils, with smaller domains resulting from systems with smaller values of the line tension. POPC (1-palmitoyl-sn-2-oleoyl-glycero-3-phosphocholine), on the other hand, acts as a line-active hybrid lipid, reducing the domain size when added in small amounts and slowing down domain coarsening. Finally, we show that despite the regulation of domain size by both methods, the phase transition temperature is influenced by the presence of oil molecules but not significantly by the presence of hybrid lipids. Overall, our results show how to regulate domain size in binary membrane model systems, over a wide range of length scales, by incorporating oil molecules and hybrid lipids.
Collapse
Affiliation(s)
- Laura Scheidegger
- Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 5, 8093 Zürich, Switzerland
| | - Laura Stricker
- Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 5, 8093 Zürich, Switzerland
| | - Peter J Beltramo
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Jan Vermant
- Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 5, 8093 Zürich, Switzerland
| |
Collapse
|
11
|
Gabriunaite I, Valiuniene A, Ramanavicius S, Ramanavicius A. Biosensors Based on Bio-Functionalized Semiconducting Metal Oxides. Crit Rev Anal Chem 2022; 54:549-564. [PMID: 35714203 DOI: 10.1080/10408347.2022.2088226] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Immobilization of biomaterials is a very important task in the development of biofuel cells and biosensors. Some semiconducting metal-oxide-based supporting materials can be used in these bioelectronics-based devices. In this article, we are reviewing some functionalization methods that are applied for the immobilization of biomaterials. The most significant attention is paid to the immobilization of biomolecules on the surface of semiconducting metal oxides. The improvement of biomaterials immobilization on metal oxides and analytical performance of biosensors by coatings based on conducting polymers, self-assembled monolayers and lipid membranes is discussed.
Collapse
Affiliation(s)
- Inga Gabriunaite
- Vilnius University, Faculty of Chemistry and Geosciences, Institute of Chemistry, Department of Physical Chemistry, Vilnius, Lithuania
| | - Ausra Valiuniene
- Vilnius University, Faculty of Chemistry and Geosciences, Institute of Chemistry, Department of Physical Chemistry, Vilnius, Lithuania
| | - Simonas Ramanavicius
- Centre for Physical Sciences and Technology, Department of Electrochemical Material Science, Vilnius, Lithuania
| | - Arunas Ramanavicius
- Vilnius University, Faculty of Chemistry and Geosciences, Institute of Chemistry, Department of Physical Chemistry, Vilnius, Lithuania
- Centre for Physical Sciences and Technology, Department of Electrochemical Material Science, Vilnius, Lithuania
| |
Collapse
|
12
|
Huang Y, Fuller G, Chandran Suja V. Physicochemical characteristics of droplet interface bilayers. Adv Colloid Interface Sci 2022; 304:102666. [PMID: 35429720 DOI: 10.1016/j.cis.2022.102666] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 04/04/2022] [Accepted: 04/05/2022] [Indexed: 11/01/2022]
Abstract
Droplet interface bilayer (DIB) is a lipid bilayer formed when two lipid monolayer-coated aqueous droplets are brought in contact within an oil phase. DIBs, especially post functionalization, are a facile model system to study the biophysics of the cell membrane. Continued advances in enhancing and functionalizing DIBs to be a faithful cell membrane mimetic requires a deep understanding of the physicochemical characteristics of droplet interface bilayers. In this review, we provide a comprehensive overview of the current scientific understanding of DIB characteristics starting with the key experimental frameworks for DIB generation, visualization and functionalization. Subsequently we report experimentally measured physical, electrical and transport characteristics of DIBs across physiologically relevant lipids. Advances in simulations and mathematical modelling of DIBs are also discussed, with an emphasis on revealing principles governing the key physicochemical characteristics. Finally, we conclude the review with important outstanding questions in the field.
Collapse
|
13
|
Kataoka-Hamai C, Kawakami K. Hydrocarbon Penetration into Phospholipid Monolayers Formed at Hydrocarbon-Water Interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:3720-3728. [PMID: 35289166 DOI: 10.1021/acs.langmuir.1c03269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Phospholipid monolayers formed at oil-water interfaces are used for various biological applications. However, monolayer structures are not well understood. Herein, we investigated hydrocarbon partitioning in 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine monolayers formed at hydrocarbon-water interfaces using fluorescence microscopy and pendant drop tensiometry. The monolayers strongly interacted with squalene, n-hexadecane, n-tetradecane, n-dodecane, n-decane, and n-butylcyclohexane. These alkane and alkylcyclohexane molecules remained within the monolayers during area compression. In contrast, the monolayers interacted weakly with n-pentylbenzene and n-butylbenzene. These alkylbenzenes were gradually removed from the monolayers upon area compression and were completely expelled at an area per lipid of ∼70 Å2. Surface pressure analysis indicated that the ability of hydrocarbons to penetrate the monolayers was enhanced in the order of n-butylbenzene < n-pentylbenzene < n-butylcyclohexane < n-hexadecane.
Collapse
Affiliation(s)
- Chiho Kataoka-Hamai
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Kohsaku Kawakami
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
- Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
| |
Collapse
|
14
|
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.
Collapse
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;
| |
Collapse
|
15
|
Janssen F, Wouters AG, Chatzigiannakis E, Delcour JA, Vermant J. Thin film drainage dynamics of wheat and rye dough liquors and oat batter liquor. Food Hydrocoll 2021. [DOI: 10.1016/j.foodhyd.2021.106624] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
|
16
|
Zoni V, Campomanes P, Vanni S. Investigating the structural properties of hydrophobic solvent-rich lipid bilayers. SOFT MATTER 2021; 17:5329-5335. [PMID: 33969832 PMCID: PMC8170560 DOI: 10.1039/d0sm02270e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 04/27/2021] [Indexed: 06/12/2023]
Abstract
In vitro reconstitutions of lipid membranes have proven to be an indispensable tool to rationalize their molecular complexity and to understand their role in countless cellular processes. However, amongst the various techniques used to reconstitute lipid bilayers in vitro, several approaches are not solvent-free, but rather contain residual hydrophobic solvents in between the two bilayer leaflets, generally as a consequence of the procedure used to generate the bilayer. To what extent the presence of these hydrophobic solvents modifies bilayer properties with respect to native, solvent-free, conditions remains an open question that has important implications for the appropriate interpretation of numerous experimental observations. Here, we thorouhgly characterize hydrophobic solvent-rich lipid bilayers using atomistic molecular dynamics simulations. Our data indicate that while the presence of hydrophobic solvents at high concentrations, such as hexadecane, has a significant effect on membrane thickness, their effects on surface properties, membrane order and lateral stress are quite moderate. Our results corroborate the validity of in vitro approaches as model systems for the investigations of biological membranes but raise a few cautionary aspects that must be considered when investigating specific membrane properties.
Collapse
Affiliation(s)
- Valeria Zoni
- Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland.
| | - Pablo Campomanes
- Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland.
| | - Stefano Vanni
- Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland.
| |
Collapse
|
17
|
Thin liquid films: Where hydrodynamics, capillarity, surface stresses and intermolecular forces meet. Curr Opin Colloid Interface Sci 2021. [DOI: 10.1016/j.cocis.2021.101441] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
|
18
|
Chatzigiannakis E, Vermant J. Dynamic stabilisation during the drainage of thin film polymer solutions. SOFT MATTER 2021; 17:4790-4803. [PMID: 33870979 DOI: 10.1039/d1sm00244a] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The drainage and rupture of polymer solutions was investigated using a dynamic thin film balance. The polymeric nature of the dissolved molecules leads to significant resistance to the deformation of the thin liquid films. The influence of concentration, molecular weight, and molecular weight distribution of the dissolved polymer on the lifetime of the films was systematically examined for varying hydrodynamic conditions. Depending on the value of the capillary number and the degree of confinement, different stabilisation mechanisms were observed. For low capillary numbers, the lifetime of the films was the highest for the highly concentrated, narrowly-distributed, low molecular weight polymers. In contrast, at high capillary numbers, the flow-induced concentration differences in the film resulted in lateral osmotic stresses, which caused a dynamic stabilisation of the films and the dependency on molecular weight distribution in particular becomes important. Phenomena such as cyclic dimple formation, vortices, and dimple recoil were observed, the occurrence of which depended on the relative magnitude of the lateral osmotic and the hydrodynamic stresses. The factors which lead to enhanced lifetime of the films as a consequence of these flow instabilities can be used to either stabilise foams or, conversely, prevent foam formation.
Collapse
Affiliation(s)
| | - Jan Vermant
- Department of Materials, ETH Zürich, 8032 Zürich, Switzerland.
| |
Collapse
|
19
|
Liu P, Zabala-Ferrera O, Beltramo PJ. Fabrication and electromechanical characterization of freestanding asymmetric membranes. Biophys J 2021; 120:1755-1764. [PMID: 33675759 PMCID: PMC8204216 DOI: 10.1016/j.bpj.2021.02.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 01/12/2021] [Accepted: 02/24/2021] [Indexed: 01/07/2023] Open
Abstract
All biological cell membranes maintain an electric transmembrane potential of around 100 mV, due in part to an asymmetric distribution of charged phospholipids across the membrane. This asymmetry is crucial to cell health and physiological processes such as intracell signaling, receptor-mediated endocytosis, and membrane protein function. Experimental artificial membrane systems incorporate essential cell membrane structures, such as the phospholipid bilayer, in a controllable manner in which specific properties and processes can be isolated and examined. Here, we describe an approach to fabricate and characterize planar, freestanding, asymmetric membranes and use it to examine the effect of headgroup charge on membrane stiffness. The approach relies on a thin film balance used to form a freestanding membrane by adsorbing aqueous phase lipid vesicles to an oil-water interface and subsequently thinning the oil to form a bilayer. We validate this lipid-in-aqueous approach by analyzing the thickness and compressibility of symmetric membranes with varying zwitterionic 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and anionic 1,2-dioleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) sodium salt (DOPG) content as compared with previous lipid-in-oil methods. We find that as the concentration of DOPG increases, membranes become thicker and stiffer. Asymmetric membranes are fabricated by controlling the lipid vesicle composition in the aqueous reservoirs on either side of the oil. Membrane compositional asymmetry is qualitatively demonstrated using a fluorescence quenching assay and quantitatively characterized through voltage-dependent capacitance measurements. Stable asymmetric membranes with DOPC on one side and DOPC-DOPG mixtures on the other were created with transmembrane potentials ranging from 15 to 80 mV. Introducing membrane charge asymmetry decreases both the thickness and stiffness in comparison with symmetric membranes with the same overall phospholipid composition. These initial successes demonstrate a viable pathway to quantitatively characterize asymmetric bilayers that can be extended to accommodate more complex membranes and membrane processes in the future.
Collapse
Affiliation(s)
- Paige Liu
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts
| | - Oscar Zabala-Ferrera
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts
| | - Peter J Beltramo
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts.
| |
Collapse
|
20
|
El-Beyrouthy J, Freeman E. Characterizing the Structure and Interactions of Model Lipid Membranes Using Electrophysiology. MEMBRANES 2021; 11:319. [PMID: 33925756 PMCID: PMC8145864 DOI: 10.3390/membranes11050319] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 04/22/2021] [Accepted: 04/25/2021] [Indexed: 11/16/2022]
Abstract
The cell membrane is a protective barrier whose configuration determines the exchange both between intracellular and extracellular regions and within the cell itself. Consequently, characterizing membrane properties and interactions is essential for advancements in topics such as limiting nanoparticle cytotoxicity. Characterization is often accomplished by recreating model membranes that approximate the structure of cellular membranes in a controlled environment, formed using self-assembly principles. The selected method for membrane creation influences the properties of the membrane assembly, including their response to electric fields used for characterizing transmembrane exchanges. When these self-assembled model membranes are combined with electrophysiology, it is possible to exploit their non-physiological mechanics to enable additional measurements of membrane interactions and phenomena. This review describes several common model membranes including liposomes, pore-spanning membranes, solid supported membranes, and emulsion-based membranes, emphasizing their varying structure due to the selected mode of production. Next, electrophysiology techniques that exploit these structures are discussed, including conductance measurements, electrowetting and electrocompression analysis, and electroimpedance spectroscopy. The focus of this review is linking each membrane assembly technique to the properties of the resulting membrane, discussing how these properties enable alternative electrophysiological approaches to measuring membrane characteristics and interactions.
Collapse
Affiliation(s)
| | - Eric Freeman
- School of Environmental, Civil, Agricultural and Mechanical Engineering, College of Engineering, University of Georgia, Athens, GA 30602, USA;
| |
Collapse
|
21
|
Huang Y, Chandran Suja V, Tajuelo J, Fuller GG. Surface energy and separation mechanics of droplet interface phospholipid bilayers. J R Soc Interface 2021; 18:20200860. [PMID: 33530859 PMCID: PMC8086854 DOI: 10.1098/rsif.2020.0860] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Accepted: 01/12/2021] [Indexed: 01/06/2023] Open
Abstract
Droplet interface bilayers are a convenient model system to study the physio-chemical properties of phospholipid bilayers, the major component of the cell membrane. The mechanical response of these bilayers to various external mechanical stimuli is an active area of research because of its implications for cellular viability and the development of artificial cells. In this article, we characterize the separation mechanics of droplet interface bilayers under step strain using a combination of experiments and numerical modelling. Initially, we show that the bilayer surface energy can be obtained using principles of energy conservation. Subsequently, we subject the system to a step strain by separating the drops in a step-wise manner, and track the evolution of the bilayer contact angle and radius. The relaxation time of the bilayer contact angle and radius along with the decay magnitude of the bilayer radius were observed to increase with each separation step. By analysing the forces acting on the bilayer and the rate of separation, we show that the bilayer separates primarily through the peeling process with the dominant resistance to separation coming from viscous dissipation associated with corner flows. Finally, we explain the intrinsic features of the observed bilayer separation by means of a mathematical model comprising the Young-Laplace equation and an evolution equation. We believe that the reported experimental and numerical results extend the scientific understanding of lipid bilayer mechanics, and that the developed experimental and numerical tools offer a convenient platform to study the mechanics of other types of bilayers.
Collapse
Affiliation(s)
- Y. Huang
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA
| | - V. Chandran Suja
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA
| | - J. Tajuelo
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA
- Departamento de Física Interdisciplinar, Universidad Nacional de Eduación a Distancia UNED, Madrid 28040, Spain
| | - G. G. Fuller
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA
| |
Collapse
|
22
|
Efficient Lipid Bilayer Formation by Dipping Lipid-Loaded Microperforated Sheet in Aqueous Solution. MICROMACHINES 2021; 12:mi12010053. [PMID: 33466555 PMCID: PMC7824848 DOI: 10.3390/mi12010053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 12/31/2020] [Accepted: 01/04/2021] [Indexed: 02/06/2023]
Abstract
This paper describes a method for a bilayer lipid membrane (BLM) formation using a perforated sheet along with an open chamber. Microscopic observation of the formed membrane showed a typical droplet interface bilayer. We proved that the formed membrane was a BLM based on electrical measurements of the membrane protein α-hemolysin, which produces nanopores in BLMs. Unlike the conventional approach for BLM formation based on the droplet contact method, this method provides aqueous surfaces with no organic solvent coating layer. Hence, this method is suitable for producing BLMs that facilitate the direct addition of chemicals into the aqueous phase.
Collapse
|
23
|
Multilayered film for the controlled formation of freestanding lipid bilayers. Colloids Surf B Biointerfaces 2020; 199:111552. [PMID: 33421926 DOI: 10.1016/j.colsurfb.2020.111552] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 12/05/2020] [Accepted: 12/19/2020] [Indexed: 11/23/2022]
Abstract
A freestanding lipid bilayer or black lipid membrane is a powerful tool for studying ion channels and for biophysical studies of other membrane proteins under controlled chemical and physical conditions. Even though the lipid bilayer has been considered an excellent sensing platform to detect diverse single molecules from nucleotides to cells, it is not yet widely used, mainly due to its low stability and the expertise needed for membrane formation. To ameliorate the issues of conventional membrane formation techniques, we report a novel layered film that consists of a nonporous layer sandwiched between two porous layers to facilitate bilayer formation. Moreover, the absorption of excess solvent present in the membrane precursor solution can be achieved by the film, enabling control over the membrane formation process. Through this layered design, we could obtain an ideal film that has a reduced and controlled membrane formation time (<30 min) and a sufficient bilayer lifetime (3 h) for ion channel studies and biosensing.
Collapse
|
24
|
Chandran Suja V, Rodríguez-Hakim M, Tajuelo J, Fuller GG. Single bubble and drop techniques for characterizing foams and emulsions. Adv Colloid Interface Sci 2020; 286:102295. [PMID: 33161297 DOI: 10.1016/j.cis.2020.102295] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/04/2020] [Accepted: 10/05/2020] [Indexed: 12/17/2022]
Abstract
The physics of foams and emulsions has traditionally been studied using bulk foam/emulsion tests and single film platforms such as the Scheludko cell. Recently there has been a renewed interest in a third class of techniques that we term as single bubble/drop tests, which employ isolated whole bubbles and drops to probe the characteristics of foams and emulsions. Single bubble and drop techniques provide a convenient framework for investigating a number of important characteristics of foams and emulsions, including the rheology, stabilization mechanisms, and rupture dynamics. In this review we provide a comprehensive discussion of the various single bubble/drop platforms and the associated experimental measurement protocols including the construction of coalescence time distributions, visualization of the thin film profiles and characterization of the interfacial rheological properties. Subsequently, we summarize the recent developments in foam and emulsion science with a focus on the results obtained through single bubble/drop techniques. We conclude the review by presenting important venues for future research.
Collapse
Affiliation(s)
- V Chandran Suja
- Department of Chemical Engineering, Stanford University, Stanford, California 94305, USA.
| | - M Rodríguez-Hakim
- Department of Chemical Engineering, Stanford University, Stanford, California 94305, USA; Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 5, Zurich 8093, Switzerland
| | - J Tajuelo
- Department of Chemical Engineering, Stanford University, Stanford, California 94305, USA; Departamento de Física Interdisciplinar, Universidad Nacional de Eduación a Distancia UNED, Madrid 28040, Spain
| | - G G Fuller
- Department of Chemical Engineering, Stanford University, Stanford, California 94305, USA.
| |
Collapse
|
25
|
Chatzigiannakis E, Veenstra P, Ten Bosch D, Vermant J. Mimicking coalescence using a pressure-controlled dynamic thin film balance. SOFT MATTER 2020; 16:9410-9422. [PMID: 32785335 DOI: 10.1039/d0sm00784f] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The dynamics of thin films containing polymer solutions are studied with a pressure-controlled thin film balance. The setup allows the control of both the magnitude and the sign as well as the duration of the pressure drop across the film. The process of coalescence can be thus studied by mimicking the evolution of pressure during the approach and separation of two bubbles. The drainage dynamics, shape evolution and stability of the films were found to depend non-trivially on the magnitude and the duration of the applied pressure. Film dynamics during the application of the negative pressure step are controlled by an interplay between capillarity and hydrodynamics. A negative hydrodynamic pressure gradient promoted the thickening of the film, while the time-dependent deformation of the Plateau border surrounding it caused its local thinning. Distinct regimes in film break-up were thus observed depending on which of these two effects prevailed. Our study provides new insight into the behaviour of films during bubble separation, allows the determination of the optimum conditions for the occurrence of coalescence, and facilitates the improvement of population balance models.
Collapse
Affiliation(s)
| | - Peter Veenstra
- Shell Global Solutions International B.V., 38000 Amsterdam, The Netherlands
| | - Dick Ten Bosch
- Shell Global Solutions International B.V., 38000 Amsterdam, The Netherlands
| | - Jan Vermant
- Department of Materials, ETH Zürich, 8032 Zürich, Switzerland.
| |
Collapse
|
26
|
Chatzigiannakis E, Vermant J. Breakup of Thin Liquid Films: From Stochastic to Deterministic. PHYSICAL REVIEW LETTERS 2020; 125:158001. [PMID: 33095612 DOI: 10.1103/physrevlett.125.158001] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 09/08/2020] [Indexed: 06/11/2023]
Abstract
The thinning and rupture of thin liquid films is a ubiquitous process, controlling the lifetime of bubbles, antibubbles, and droplets. A better understanding of rupture is important for controlling and modeling the stability of multiphase products. Yet literature reports that film breakup can be either stochastic or deterministic. Here, we employ a modified thin film balance to vary the ratio of hydrodynamic to capillary stresses and its role on the dynamics of thin liquid films of polymer solutions with adequate viscosities. Varying the pressure drop across planar films allows us to control the ratio of the two competing timescales, i.e., a controlled hydrodynamic drainage time and a timescale related to fluctuations. The thickness fluctuations are visualized and quantified, and their characteristics are for the first time directly measured experimentally for varying strengths of the flow inside the film. We show how the criteria for rupture depend on the hydrodynamic conditions, changing from stochastic to deterministic as the hydrodynamic forces inside the film damp the fluctuations.
Collapse
Affiliation(s)
| | - Jan Vermant
- Department of Materials, ETH Zürich, Vladimir Prelog Weg 5, 8032 Zürich, Switzerland
| |
Collapse
|
27
|
Lee HR, Lee Y, Oh SS, Choi SQ. Ultra-Stable Freestanding Lipid Membrane Array: Direct Visualization of Dynamic Membrane Remodeling with Cholesterol Transport and Enzymatic Reactions. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e2002541. [PMID: 32924281 DOI: 10.1002/smll.202002541] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 07/09/2020] [Indexed: 06/11/2023]
Abstract
Cell membranes actively change their local compositions, serving essential biological processes such as cellular signaling and endocytosis. Although membrane dynamics is vital in the cellular functions, the complexity of natural membranes has made its fundamental understanding and systematic assessment difficult. Here, a powerful artificial membrane system is developed for real-time visualization of the spatiotemporal dynamics of membrane remodeling. Through well-defined air/oil/water interfaces on grid holes, tens of planar lipid bilayer membranes are easily created, and their reproducibility, controllability, and generality are highlighted. The freestanding membranes are large but also highly stable, facilitating direct long-term monitoring of dynamic membrane reconstitution caused by external stimuli. As an example to demonstrate the superiority of this membrane system, the effect of cholesterol trafficking, which significantly affects biophysical properties of cell membranes, is investigated at different membrane compositions. Cholesterol transport into and out of the membranes at different rates causes anomalous lipid arrangements through cholesterol-mediated phase transitions and decomposition, which have never been witnessed before. Furthermore, enzyme-induced membrane dynamics is successfully shown in this platform; sphingomyelinases locally generate asymmetry between two membrane leaflets. This technique is broadly applicable for exploring the membrane heterogeneity under various membrane-based reactions, providing valuable insight into the membrane dynamics.
Collapse
Affiliation(s)
- Hyun-Ro Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Yohan Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Seung Soo Oh
- Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
| | - Siyoung Q Choi
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| |
Collapse
|
28
|
Ardham VR, Zoni V, Adamowicz S, Campomanes P, Vanni S. Accurate Estimation of Membrane Capacitance from Atomistic Molecular Dynamics Simulations of Zwitterionic Lipid Bilayers. J Phys Chem B 2020; 124:8278-8286. [PMID: 32856913 DOI: 10.1021/acs.jpcb.0c03145] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Lipid membranes are indispensable to life, and they regulate countless cellular processes. To investigate the properties of membranes under controlled conditions, numerous reconstitution methods have been developed over the last few decades. Several of these methods result in the formation of lipid bilayers containing residual hydrophobic molecules between the two monolayers. These contaminants might alter membrane properties, including bilayer thickness, that is usually inferred from measurements of membrane capacitance assuming a simple slab model. However, recent measurements on solvent-free bilayers raised significant questions on the reliability of this approach. To reconcile the observed discrepancies, we developed a protocol to predict membrane capacitance from the dielectric profile of lipid bilayers computed from molecular dynamics simulations. Our methodology shows excellent agreement against available data on solvent-free noncharged bilayers, and it confirms that the uniform slab model is a reliable approximation from which to infer membrane capacitance. We find that the effective electrical thickness contributing to membrane capacitance is different from the hydrophobic thickness inferred from X-ray scattering form factors. We apply our model to estimate the concentration of residual solvent in reconstituted systems, and we propose that our protocol could be used to infer membrane properties in the presence of hydrophobic solvents.
Collapse
Affiliation(s)
- Vikram Reddy Ardham
- Chemin du Musée 10, Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland
| | - Valeria Zoni
- Chemin du Musée 10, Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland
| | - Sylvain Adamowicz
- Chemin du Musée 10, Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland
| | - Pablo Campomanes
- Chemin du Musée 10, Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland
| | - Stefano Vanni
- Chemin du Musée 10, Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland
| |
Collapse
|
29
|
Rofeh J, Theogarajan L. Instantaneous tension measurements in droplet interface bilayers using an inexpensive, integrated pendant drop camera. SOFT MATTER 2020; 16:4484-4493. [PMID: 32337523 DOI: 10.1039/d0sm00418a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Recently, droplet interface bilayers (DIBs) have been used to determine bilayer tension and thickness in situ by automated image analysis using a microscope and an applied voltage. In this paper, we demonstrate improvements to these measurements by integrating an inexpensive pendant drop setup onto the microscope stage, which allows for simultaneous imaging of DIBs from both the bottom and side. By using pendant drop shape analysis in situ to determine the monolayer tension of the droplets, we avoid the reliance on applied voltages to determine tension. The integrated system also allows for direct measurement of both the major and minor diameter of the elliptical contact region, which produces a more direct measurement of the bilayer specific capacitance. Additionally, we demonstrate a technique for measuring the instantaneous monolayer tension of DIBs using shape analysis despite the assumed requirement for axial symmetry in pendant drop tensiometry. Compared to previous DIB measurements, the integrated pendant drop-microscope system provides improved accuracy accompanied by a fivefold to twentyfold improvement in precision while considerably decreasing the experiment time.
Collapse
Affiliation(s)
- Justin Rofeh
- Department of Physics, University of California, Santa Barbara, California 93106, USA
| | - Luke Theogarajan
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, California 93106, USA.
| |
Collapse
|
30
|
Surface Sensitive Analysis Device using Model Membrane and Challenges for Biosensor-chip. BIOCHIP JOURNAL 2020. [DOI: 10.1007/s13206-019-4110-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
31
|
Dols-Perez A, Marin V, Amador GJ, Kieffer R, Tam D, Aubin-Tam ME. Artificial Cell Membranes Interfaced with Optical Tweezers: A Versatile Microfluidics Platform for Nanomanipulation and Mechanical Characterization. ACS APPLIED MATERIALS & INTERFACES 2019; 11:33620-33627. [PMID: 31448892 PMCID: PMC6753654 DOI: 10.1021/acsami.9b09983] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Cell lipid membranes are the site of vital biological processes, such as motility, trafficking, and sensing, many of which involve mechanical forces. Elucidating the interplay between such bioprocesses and mechanical forces requires the use of tools that apply and measure piconewton-level forces, e.g., optical tweezers. Here, we introduce the combination of optical tweezers with free-standing lipid bilayers, which are fully accessible on both sides of the membrane. In the vicinity of the lipid bilayer, optical trapping would normally be impossible due to optical distortions caused by pockets of the solvent trapped within the membrane. We solve this by drastically reducing the size of these pockets via tuning of the solvent and flow cell material. In the resulting flow cells, lipid nanotubes are straightforwardly pushed or pulled and reach lengths above half a millimeter. Moreover, the controlled pushing of a lipid nanotube with an optically trapped bead provides an accurate and direct measurement of important mechanical properties. In particular, we measure the membrane tension of a free-standing membrane composed of a mixture of dioleoylphosphatidylcholine (DOPC) and dipalmitoylphosphatidylcholine (DPPC) to be 4.6 × 10-6 N/m. We demonstrate the potential of the platform for biophysical studies by inserting the cell-penetrating trans-activator of transcription (TAT) peptide in the lipid membrane. The interactions between the TAT peptide and the membrane are found to decrease the value of the membrane tension to 2.1 × 10-6 N/m. This method is also fully compatible with electrophysiological measurements and presents new possibilities for the study of membrane mechanics and the creation of artificial lipid tube networks of great importance in intra- and intercellular communication.
Collapse
Affiliation(s)
- Aurora Dols-Perez
- Department
of Bionanoscience, Kavli Institute of Nanoscience,
Delft University of Technology, Van der Maasweg 9, Delft 2629 HZ, The Netherlands
| | - Victor Marin
- Department
of Bionanoscience, Kavli Institute of Nanoscience,
Delft University of Technology, Van der Maasweg 9, Delft 2629 HZ, The Netherlands
| | - Guillermo J. Amador
- Department
of Bionanoscience, Kavli Institute of Nanoscience,
Delft University of Technology, Van der Maasweg 9, Delft 2629 HZ, The Netherlands
- Laboratory
for Aero and Hydrodynamics, Delft University
of Technology, Delft 2628 CD, The Netherlands
| | - Roland Kieffer
- Department
of Bionanoscience, Kavli Institute of Nanoscience,
Delft University of Technology, Van der Maasweg 9, Delft 2629 HZ, The Netherlands
| | - Daniel Tam
- Laboratory
for Aero and Hydrodynamics, Delft University
of Technology, Delft 2628 CD, The Netherlands
| | - Marie-Eve Aubin-Tam
- Department
of Bionanoscience, Kavli Institute of Nanoscience,
Delft University of Technology, Van der Maasweg 9, Delft 2629 HZ, The Netherlands
- E-mail: (M.A.)
| |
Collapse
|
32
|
Tsemperouli M, Amstad E, Sakai N, Matile S, Sugihara K. Black Lipid Membranes: Challenges in Simultaneous Quantitative Characterization by Electrophysiology and Fluorescence Microscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:8748-8757. [PMID: 31244250 DOI: 10.1021/acs.langmuir.9b00673] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Horizontal black lipid membranes (BLMs) enable optical microscopy to be combined with the electrophysiological measurements for studying ion channels, peptide pores, and ionophores. However, a careful literature review reveals that simultaneous fluorescence and electrical recordings in horizontal BLMs have been rarely reported for an unclear reason, whereas many works employ bright-field microscopy instead of fluorescence microscopy or perform fluorescence imaging and electrical measurements one after another separately without truly exploiting the advantage of the combined setup. In this work, the major causes related to the simultaneous electrical and fluorescence recordings in horizontal BLMs are identified, and several solutions to counteract the issue are also proposed.
Collapse
Affiliation(s)
- Maria Tsemperouli
- School of Chemistry and Biochemistry , University of Geneva , CH-1211 Geneva , Switzerland
| | - Esther Amstad
- Institute of Materials , Ecole Polytechnique Fédérale de Lausanne , 1015 Lausanne , Switzerland
| | - Naomi Sakai
- School of Chemistry and Biochemistry , University of Geneva , CH-1211 Geneva , Switzerland
| | - Stefan Matile
- School of Chemistry and Biochemistry , University of Geneva , CH-1211 Geneva , Switzerland
| | - Kaori Sugihara
- School of Chemistry and Biochemistry , University of Geneva , CH-1211 Geneva , Switzerland
| |
Collapse
|
33
|
Heo P, Ramakrishnan S, Coleman J, Rothman JE, Fleury JB, Pincet F. Highly Reproducible Physiological Asymmetric Membrane with Freely Diffusing Embedded Proteins in a 3D-Printed Microfluidic Setup. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2019; 15:e1900725. [PMID: 30977975 DOI: 10.1002/smll.201900725] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 03/28/2019] [Indexed: 06/09/2023]
Abstract
Experimental setups to produce and to monitor model membranes have been successfully used for decades and brought invaluable insights into many areas of biology. However, they all have limitations that prevent the full in vitro mimicking and monitoring of most biological processes. Here, a suspended physiological bilayer-forming chip is designed from 3D-printing techniques. This chip can be simultaneously integrated to a confocal microscope and a path-clamp amplifier. It is composed of poly(dimethylsiloxane) and consists of a ≈100 µm hole, where the horizontal planar bilayer is formed, connecting two open crossed-channels, which allows for altering of each lipid monolayer separately. The bilayer, formed by the zipping of two lipid leaflets, is free-standing, horizontal, stable, fluid, solvent-free, and flat with the 14 types of physiologically relevant lipids, and the bilayer formation process is highly reproducible. Because of the two channels, asymmetric bilayers can be formed by making the two lipid leaflets of different composition. Furthermore, proteins, such as transmembrane, peripheral, and pore-forming proteins, can be added to the bilayer in controlled orientation and keep their native mobility and activity. These features allow in vitro recapitulation of membrane process close to physiological conditions.
Collapse
Affiliation(s)
- Paul Heo
- Laboratoire de Physique de l'Ecole Normale Supérieure, PSL Research University, CNRS, Sorbonne Université, Université Sorbonne Paris Cité, Paris, 75005, France
| | - Sathish Ramakrishnan
- Laboratoire de Physique de l'Ecole Normale Supérieure, PSL Research University, CNRS, Sorbonne Université, Université Sorbonne Paris Cité, Paris, 75005, France
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, 06510, USA
| | - Jeff Coleman
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, 06510, USA
| | - James E Rothman
- Ecole Normale Supérieure, PSL University, Paris, 75005, France
| | - Jean-Baptiste Fleury
- Department of Experimental Physics and Center for Biophysics, Saarland University, Saarbruecken, D-66123, Germany
| | - Frederic Pincet
- Laboratoire de Physique de l'Ecole Normale Supérieure, PSL Research University, CNRS, Sorbonne Université, Université Sorbonne Paris Cité, Paris, 75005, France
| |
Collapse
|
34
|
Vitkova V, Mitkova D, Antonova K, Popkirov G, Dimova R. Sucrose solutions alter the electric capacitance and dielectric permittivity of lipid bilayers. Colloids Surf A Physicochem Eng Asp 2018. [DOI: 10.1016/j.colsurfa.2018.05.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
35
|
|
36
|
Arai S, Inoue S, Hamai T, Kumai R, Hasegawa T. Semiconductive Single Molecular Bilayers Realized Using Geometrical Frustration. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1707256. [PMID: 29691910 DOI: 10.1002/adma.201707256] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 03/03/2018] [Indexed: 06/08/2023]
Abstract
A unique solution-based technology to manufacture self-assembled ultrathin organic-semiconductor layers with ultrauniform single-molecular-bilayer thickness over an area as large as wafer scale is developed. A novel concept is adopted in this technique, based upon the idea of geometrical frustration, which can effectively suppress the interlayer stacking (or multilayer crystallization) while maintaining the assembly of the intralayer, which originates from the strong intermolecular interactions between π-conjugated molecules. For this purpose, a mixed solution of extended π-conjugated frameworks substituted asymmetrically by alkyl chains of variable lengths (i.e., (πCore)-Cn 's) is utilized for the solution process. A simple blade-coating with a solution containing two (πCore)-Cn 's with different alkyl chain lengths is effective to provide single molecular bilayers (SMBs) composed of a pair of polar monomolecular layers, which is analogical to the cell membranes of living organisms. It is demonstrated that the chain-length disorder does not perturb the in-plane crystalline order, but acts effectively as a geometrical frustration to inhibit multilayer crystallization. The uniformity, stability, and size scale are unprecedented, as produced by other conventional self-assembly processes. The obtained SMBs also exhibit efficient 2D carrier transport as organic thin-film transistors. This finding should open a new route to SMB-based ultrathin superflexible electronics.
Collapse
Affiliation(s)
- Shunto Arai
- Department of Applied Physics, The University of Tokyo, Tokyo, 113-8656, Japan
| | | | - Takamasa Hamai
- Department of Applied Physics, The University of Tokyo, Tokyo, 113-8656, Japan
| | - Reiji Kumai
- Condensed Matter Research Centre (CMRC) and Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Tsukuba, 305-0801, Japan
| | - Tatsuo Hasegawa
- Department of Applied Physics, The University of Tokyo, Tokyo, 113-8656, Japan
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, 305-8565, Japan
| |
Collapse
|
37
|
Beltramo PJ, Scheidegger L, Vermant J. Toward Realistic Large-Area Cell Membrane Mimics: Excluding Oil, Controlling Composition, and Including Ion Channels. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:5880-5888. [PMID: 29715042 DOI: 10.1021/acs.langmuir.8b00837] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Capacitance measurements provide unique insights into the thickness, compressibility, and composition of large-area membrane bilayers and are used here in addition to demonstrate the successful incorporation of model ion channels. The simultaneous ability to control the bilayer size, manipulate tension, and optically monitor and electrically stimulate freestanding membranes enables precise determination of their specific capacitance and thickness across a wide range of areas. We confirm that membranes formed by this recently developed technique have capacitive properties similar to those formed by existing protocols, including solvent-free approaches, and discuss the effect using either hexadecane or squalene as the oil solvent. The results obtained here are relevant for other methods where lipid membranes are reconstituted from a bulk oil solvent. Because biological membranes have a diverse phospholipid profile, we show that the technique can successfully reconstitute membranes with binary composition mixtures. As an outlook, we show the capability of model membrane proteins, specifically α-hemolysin and alamethicin, to be incorporated into the formed bilayers and measure ion transport.
Collapse
Affiliation(s)
- Peter J Beltramo
- Department of Chemical Engineering , University of Massachusetts Amherst , Amherst , Massachusetts 01003 , United States
| | - Laura Scheidegger
- Department of Materials , ETH Zürich , Vladimir-Prelog-Weg 5 , 8093 Zürich , Switzerland
| | - Jan Vermant
- Department of Materials , ETH Zürich , Vladimir-Prelog-Weg 5 , 8093 Zürich , Switzerland
| |
Collapse
|
38
|
Yilixiati S, Rafiq R, Zhang Y, Sharma V. Influence of Salt on Supramolecular Oscillatory Structural Forces and Stratification in Micellar Freestanding Films. ACS NANO 2018; 12:1050-1061. [PMID: 29314826 DOI: 10.1021/acsnano.7b05391] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Freestanding films of soft matter containing micelles, nanoparticles, polyelectrolyte-surfactant complexes, bilayers, and smectic liquid crystals exhibit stratification. Stepwise thinning and coexisting thick-thin regions associated with drainage via stratification are attributed to the confinement-induced structuring and layering of supramolecular structures, which contribute supramolecular oscillatory structural forces. In freestanding micellar films, formed by a solution of an ionic surfactant above its critical micelle concentration, both interfacial adsorption and the micelle size and shape are determined by the concentration of surfactant and of added electrolytes. Although the influence of surfactant concentration on stratification has been investigated before, the influence of added salt, at concentrations typically found in water used on a daily basis, has not been investigated yet. In this contribution, we elucidate how the addition of salt affects stepwise thinning: step size, number of steps, as well as the shape and size of nanoscopic nonflat structures such as mesas in micellar foam films formed with aqueous solutions of anionic surfactant (sodium dodecyl sulfate (SDS)). The nanoscopic thickness variations and transitions are visualized and analyzed using IDIOM (Interferometry Digital Imaging Optical Microscopy) protocols with exquisite spatiotemporal resolution (thickness ∼1 nm, time <1 ms). In contrast to nanoparticle dispersions that show no influence of salt on step size, we find that the addition of salt to micellar freestanding films results in a decrease in step size as well as the number of stepwise transitions, in addition to changes in nucleation and growth of mesas, all driven by the corresponding change in supramolecular oscillatory structural forces.
Collapse
Affiliation(s)
- Subinuer Yilixiati
- Chemical Engineering, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Rabees Rafiq
- Chemical Engineering, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Yiran Zhang
- Chemical Engineering, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Vivek Sharma
- Chemical Engineering, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| |
Collapse
|
39
|
Lee Y, Lee HR, Kim K, Choi SQ. Static and Dynamic Permeability Assay for Hydrophilic Small Molecules Using a Planar Droplet Interface Bilayer. Anal Chem 2018; 90:1660-1667. [PMID: 29308648 DOI: 10.1021/acs.analchem.7b03004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Because numerous drugs are administered through an oral route and primarily absorbed at the intestine, the prediction of drug permeability across an intestinal epithelial cell membrane has been a crucial issue in drug discovery. Thus, various in vitro permeability assays have been developed such as the Caco-2 assay, the parallel artificial membrane permeability assay (PAMPA), the phospholipid vesicle-based permeation assays (PVPA) and Permeapad. However, because of the time-consuming and quite expensive process for culturing cells in the Caco-2 assay and the unknown microscopic membrane structures of the other assays, a simpler yet more accurate and versatile technique is still required. Accordingly, we developed a new platform to measure the permeability of small molecules across a planar freestanding lipid bilayer with a well-defined area and structure. The lipid bilayer was constructed within a conventional UV spectrometer cell, and the transport of drug molecules across the bilayer was recorded by UV absorbance over time. We then computed the permeability from the time-dependent diffusion equation. We tested this assay for five exemplary hydrophilic drugs and compared their values with previously reported ones. We found that our assay has a much higher permeability compared to the other techniques, and this higher permeability is related to the thickness of the lipid bilayer. Also we were able to measure the dynamic permeability upon the addition of a membrane-disrupting surfactant demonstrating that our assay has the capability to detect real-time changes in permeability across the lipid bilayer.
Collapse
Affiliation(s)
- Yohan Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141, Korea
| | - Hyun-Ro Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141, Korea
| | - KyuHan Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141, Korea
| | - Siyoung Q Choi
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141, Korea
| |
Collapse
|
40
|
Kim H, Kim K, Lee HR, Jo H, Jeong DW, Ryu J, Gweon DG, Choi SQ. Formation of stable adhesive water-in-oil emulsions using a phospholipid and cosurfactants. J IND ENG CHEM 2017. [DOI: 10.1016/j.jiec.2017.06.046] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
41
|
Abstract
A strategy to halt dissolution of particle-coated air bubbles in water based on interfacial rheology design is presented. Whereas previously a dense monolayer was believed to be required for such an "armored bubble" to resist dissolution, in fact engineering a 2D yield stress interface suffices to achieve such performance at submonolayer particle coverages. We use a suite of interfacial rheology techniques to characterize spherical and ellipsoidal particles at an air-water interface as a function of surface coverage. Bubbles with varying particle coverages are made and their resistance to dissolution evaluated using a microfluidic technique. Whereas a bare bubble only has a single pressure at which a given radius is stable, we find a range of pressures over which bubble dissolution is arrested for armored bubbles. The link between interfacial rheology and macroscopic dissolution of [Formula: see text] 100 [Formula: see text]m bubbles coated with [Formula: see text] 1 [Formula: see text]m particles is presented and discussed. The generic design rationale is confirmed by using nonspherical particles, which develop significant yield stress at even lower surface coverages. Hence, it can be applied to successfully inhibit Ostwald ripening in a multitude of foam and emulsion applications.
Collapse
|
42
|
Johnson A, Bao P, Hurley CR, Cartron M, Evans SD, Hunter CN, Leggett GJ. Simple, Direct Routes to Polymer Brush Traps and Nanostructures for Studies of Diffusional Transport in Supported Lipid Bilayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:3672-3679. [PMID: 28350169 PMCID: PMC5459270 DOI: 10.1021/acs.langmuir.7b00497] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 03/23/2017] [Indexed: 06/06/2023]
Abstract
Patterned poly(oligo ethylene glycol) methyl ether methacrylate (POEGMEMA) brush structures may be formed by using a combination of atom-transfer radical polymerization (ATRP) and UV photopatterning. UV photolysis is used to selectively dechlorinate films of 4-(chloromethyl)phenyltrichlorosilane (CMPTS) adsorbed on silica surfaces, by exposure either through a mask or using a two-beam interferometer. Exposure through a mask yields patterns of carboxylic acid-terminated adsorbates. POEGMEMA may be grown from intact Cl initiators that were masked during exposure. Corrals, traps, and other structures formed in this way enable the patterning of proteins, vesicles, and, following vesicle rupture, supported lipid bilayers (SLBs). Bilayers adsorbed on the carboxylic acid-terminated surfaces formed by C-Cl bond photolysis in CMPTS exhibit high mobility. SLBs do not form on POEGMEMA. Using traps consisting of carboxylic acid-functionalized regions enclosed by POEGMEMA structures, electrophoresis may be observed in lipid bilayers containing a small amount of a fluorescent dye. Segregation of dye at one end of the traps was measured by fluorescence microscopy. The increase in the fluorescence intensity was found to be proportional to the trap length, while the time taken to reach the maximum value was inversely proportional to the trap length, indicating uniform, rapid diffusion in all of the traps. Nanostructured materials were formed using interferometric lithography. Channels were defined by exposure of CMPTS films to maxima in the interferogram, and POEGMEMA walls were formed by ATRP. As for the micrometer-scale patterns, bilayers did not form on the POEGMEMA structures, and high lipid mobilities were measured in the polymer-free regions of the channels.
Collapse
Affiliation(s)
- Alexander Johnson
- Department
of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, United
Kingdom
- Krebs
Institute, University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Peng Bao
- Molecular
and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United
Kingdom
| | - Claire R. Hurley
- Department
of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, United
Kingdom
| | - Michaël Cartron
- Department
of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom
| | - Stephen D. Evans
- Molecular
and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United
Kingdom
| | - C. Neil Hunter
- Department
of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom
| | - Graham J. Leggett
- Department
of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, United
Kingdom
- Krebs
Institute, University of Sheffield, Sheffield S10 2TN, United Kingdom
| |
Collapse
|
43
|
Affiliation(s)
- Toshihisa Osaki
- Artificial Cell
Membrane
Systems Group, Kanagawa Academy of Science and Technology, 3-2-1
Sakado, Takatsu, 213-0012 Kawasaki, Japan
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro, 153-8505 Tokyo, Japan
| | - Shoji Takeuchi
- Artificial Cell
Membrane
Systems Group, Kanagawa Academy of Science and Technology, 3-2-1
Sakado, Takatsu, 213-0012 Kawasaki, Japan
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro, 153-8505 Tokyo, Japan
| |
Collapse
|
44
|
Frostad JM, Tammaro D, Santollani L, Bochner de Araujo S, Fuller GG. Dynamic fluid-film interferometry as a predictor of bulk foam properties. SOFT MATTER 2016; 12:9266-9279. [PMID: 27752701 DOI: 10.1039/c6sm01361a] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Understanding and enabling the control of the properties of foams is important for a variety of commercial processes and consumer products. In these systems, the role of surface active compounds has been the subject of many investigations using a wide range of techniques. The study of their influence on simplified geometries such as two bubbles in a liquid or a thin film of solution (such as in the well-known Scheludko cell), has yielded important fundamental understanding. Similarly, in this work an interferometric technique is used to study the dynamic evolution of the film formed by a single bubble being pressed against a planar air-liquid interface. Here interferometry is used to dynamically measure the total volume of liquid contained within the thin-film region between the bubble and the planar interface. Three different small-molecule, surfactant solutions were investigated and the data obtained via interferometry were compared to measurements of the density of bulk foams of the same solutions. The density measurements were collected with a simple, but novel technique using a conical-shaped bubbling apparatus. The results reveal a strong correlation between the measurements on single bubbles and complete foams. This suggests that further investigations using interferometric techniques can be instrumental to building a more detailed mechanistic understanding of how different surface-active compounds influence foam properties. The results also reveal that the commonly used assumption that surfactant-laden interfaces may be modeled as immobile, is too simplistic to accurately model interfaces with small-molecule surfactants.
Collapse
Affiliation(s)
- John M Frostad
- Stanford University, Department of Chemical Engineering, Stanford, USA
| | - Daniele Tammaro
- University of Naples Federico II, Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale, P.le Tecchio 80, I-80125 Napoli, Italy
| | | | | | - Gerald G Fuller
- Stanford University, Department of Chemical Engineering, Stanford, USA
| |
Collapse
|
45
|
Beltramo PJ, Vermant J. Simple Optical Imaging of Nanoscale Features in Free-Standing Films. ACS OMEGA 2016; 1:363-370. [PMID: 30023480 PMCID: PMC6044614 DOI: 10.1021/acsomega.6b00125] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 08/31/2016] [Indexed: 05/19/2023]
Abstract
Measuring thicknesses in thin films with high spatial and temporal resolution is of prime importance for understanding the structure and dynamics in thin films and membranes. In the present work, we introduce fluorescence-interferometry, a method that combines standard reflected light thin film interferometry with simultaneous fluorescence measurements. We apply this method to the thinning dynamics and phase separation in free-standing inverse phospholipid bilayer films. The measurements were carried out using a standard fluorescence microscope using multichannel imaging and yielded subnanometer resolution, which is applied to optically measure the discrete thickness variations across phase-separated membranes.
Collapse
|