1
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Sakaya A, Durantini AM, Gidi Y, Šverko T, Wieczny V, McCain J, Cosa G. Fluorescence-Amplified Detection of Redox Turnovers in Supported Lipid Bilayers Illuminates Redox Processes of α-Tocopherol. ACS APPLIED MATERIALS & INTERFACES 2022; 14:13872-13882. [PMID: 35266688 DOI: 10.1021/acsami.1c23931] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Electron-transfer processes in lipid membranes are key to biological functions, yet challenging to study because of the intrinsic heterogeneity of the systems. Here, we report spectro-electrochemical measurements on indium tin oxide-supported lipid bilayers toward the selective induction and sensing of redox processes in membranes. Working at neutral pH with a fluorogenic α-tocopherol analogue, the dynamics of the two-electron oxidation of the chromanol to a chromanone and the rapid thermal decay of the latter to a chromoquinone are recorded as a rapid surge and drop in intensity, respectively. Continuous voltage cycling reveals rapid chromoquinone two-electron, two-proton reduction to dihydrochromoquinone at negative bias, followed by slow regeneration of the former at positive bias. The kinetic parameters of these different transitions are readily obtained as a function of applied potentials. The sensitivity and selectivity afforded by the reported method enables monitoring signals equivalent to femtoampere currents with a high signal-to-background ratio. The study provides a new method to monitor membrane redox processes with high sensitivity and minimal concentrations and unravels key dynamic aspects of α-tocopherol redox chemistry.
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Affiliation(s)
- Aya Sakaya
- Department of Chemistry and Quebec Center for Advanced Materials (QCAM), McGill University, 801 Sherbrooke Street West, Montreal, Québec H3A 0B8, Canada
| | - Andrés M Durantini
- Department of Chemistry and Quebec Center for Advanced Materials (QCAM), McGill University, 801 Sherbrooke Street West, Montreal, Québec H3A 0B8, Canada
| | - Yasser Gidi
- Department of Chemistry and Quebec Center for Advanced Materials (QCAM), McGill University, 801 Sherbrooke Street West, Montreal, Québec H3A 0B8, Canada
| | - Tara Šverko
- Department of Chemistry and Quebec Center for Advanced Materials (QCAM), McGill University, 801 Sherbrooke Street West, Montreal, Québec H3A 0B8, Canada
| | - Vincent Wieczny
- Department of Chemistry and Quebec Center for Advanced Materials (QCAM), McGill University, 801 Sherbrooke Street West, Montreal, Québec H3A 0B8, Canada
| | - Julia McCain
- Department of Chemistry and Quebec Center for Advanced Materials (QCAM), McGill University, 801 Sherbrooke Street West, Montreal, Québec H3A 0B8, Canada
| | - Gonzalo Cosa
- Department of Chemistry and Quebec Center for Advanced Materials (QCAM), McGill University, 801 Sherbrooke Street West, Montreal, Québec H3A 0B8, Canada
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2
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Liu HY, Chen WL, Ober CK, Daniel S. Biologically Complex Planar Cell Plasma Membranes Supported on Polyelectrolyte Cushions Enhance Transmembrane Protein Mobility and Retain Native Orientation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:1061-1072. [PMID: 29020444 DOI: 10.1021/acs.langmuir.7b02945] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Reconstituted supported lipid bilayers (SLB) are widely used as in vitro cell-surface models because they are compatible with a variety of surface-based analytical techniques. However, one of the challenges of using SLBs as a model of the cell surface is the limited complexity in membrane composition, including the incorporation of transmembrane proteins and lipid diversity that may impact the activity of those proteins. Additionally, it is challenging to preserve the transmembrane protein native orientation, function, and mobility in SLBs. Here, we leverage the interaction between cell plasma membrane vesicles and polyelectrolyte brushes to create planar bilayers from cell plasma membrane vesicles that have budded from the cell surface. This approach promotes the direct incorporation of membrane proteins and other species into the planar bilayer without using detergent or reconstitution and preserves membrane constituents. Furthermore, the structure of the polyelectrolyte brush serves as a cushion between the planar bilayer and rigid supporting surface, limiting the interaction of the cytosolic domains of membrane proteins with this surface. Single particle tracking was used to analyze the motion of GPI-linked yellow fluorescent proteins (GPI-YFP) and neon-green fused transmembrane P2X2 receptors (P2X2-neon) and shows that this platform retains over 75% mobility of multipass transmembrane proteins in its native membrane environment. An enzyme accessibility assay confirmed that the protein orientation is preserved and results in the extracellular domain facing toward the bulk phase and the cytosolic side facing the support. Because the platform presented here retains the complexity of the cell plasma membrane and preserves protein orientation and mobility, it is a better representative mimic of native cell surfaces, which may find many applications in biological assays aimed at understanding cell membrane phenomena.
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Affiliation(s)
- Han-Yuan Liu
- Robert F. Smith School of Chemical and Biomolecular Engineering, ‡Department of Material Science and Engineering, Cornell University , Ithaca, New York 14853, United States
| | - Wei-Liang Chen
- Robert F. Smith School of Chemical and Biomolecular Engineering, ‡Department of Material Science and Engineering, Cornell University , Ithaca, New York 14853, United States
| | - Christopher K Ober
- Robert F. Smith School of Chemical and Biomolecular Engineering, ‡Department of Material Science and Engineering, Cornell University , Ithaca, New York 14853, United States
| | - Susan Daniel
- Robert F. Smith School of Chemical and Biomolecular Engineering, ‡Department of Material Science and Engineering, Cornell University , Ithaca, New York 14853, United States
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3
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Yao X, Chen L, Ju J, Li C, Tian Y, Jiang L, Liu M. Superhydrophobic Diffusion Barriers for Hydrogels via Confined Interfacial Modification. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2016; 28:7383-9. [PMID: 27309131 DOI: 10.1002/adma.201601568] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 05/12/2016] [Indexed: 05/21/2023]
Abstract
A ubiquitous strategy to superhydrophobize the surfaces of synthetic hydrogels is reported, creating heterogeneous wettability across the surface and the inner network. Such wetting disparity shows significant influence on preventing immediate diffusion of substances between the hydrogel and the aqueous environment on different scales.
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Affiliation(s)
- Xi Yao
- Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, School of Chemistry and Environment, Beihang University, Beijing, 100191, P. R. China
| | - Lie Chen
- Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, School of Chemistry and Environment, Beihang University, Beijing, 100191, P. R. China
| | - Jie Ju
- Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Changhua Li
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Nankai University, Tianjin, 300071, P. R. China
| | - Ye Tian
- Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Lei Jiang
- Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, School of Chemistry and Environment, Beihang University, Beijing, 100191, P. R. China
- Laboratory of Bioinspired Smart Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Mingjie Liu
- Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, School of Chemistry and Environment, Beihang University, Beijing, 100191, P. R. China.
- International Research Institute for Multidisciplinary Science, Beihang University, Beijing, 100191, P. R. China.
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4
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Palivan CG, Goers R, Najer A, Zhang X, Car A, Meier W. Bioinspired polymer vesicles and membranes for biological and medical applications. Chem Soc Rev 2016; 45:377-411. [DOI: 10.1039/c5cs00569h] [Citation(s) in RCA: 413] [Impact Index Per Article: 51.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Biological membranes play an essential role in living organisms by providing stable and functional compartments, supporting signalling and selective transport. Combining synthetic polymer membranes with biological molecules promises to be an effective strategy to mimic the functions of cell membranes and apply them in artificial systems.
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Affiliation(s)
| | - Roland Goers
- Department of Chemistry
- University of Basel
- CH-4056 Basel
- Switzerland
- Department of Biosystems Science and Engineering
| | - Adrian Najer
- Department of Chemistry
- University of Basel
- CH-4056 Basel
- Switzerland
| | - Xiaoyan Zhang
- Department of Chemistry
- University of Basel
- CH-4056 Basel
- Switzerland
| | - Anja Car
- Department of Chemistry
- University of Basel
- CH-4056 Basel
- Switzerland
| | - Wolfgang Meier
- Department of Chemistry
- University of Basel
- CH-4056 Basel
- Switzerland
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5
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Wlodek M, Szuwarzynski M, Kolasinska-Sojka M. Effect of Supporting Polyelectrolyte Multilayers and Deposition Conditions on the Formation of 1-Palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine/1-Palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine Lipid Bilayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:10484-10492. [PMID: 26334376 DOI: 10.1021/acs.langmuir.5b02560] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The formation of complete supported lipid bilayers by vesicle adsorption and rupture was studied in relation to deposition conditions of vesicles and underlying cushion formed from various polyelectrolytes. Lipid vesicles were formed from zwitterionic 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and negatively charged 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE) in phosphate buffer of various pH with or without NaCl addition. Polyelectrolyte multilayer films (PEM) were constructed by sequential adsorption of alternately charged polyelectrolytes from their solutions-layer-by-layer deposition (LBL). The mechanism of the formation of supported lipid bilayer on polyelectrolyte films was studied by quartz crystal microbalance with dissipation monitoring (QCM-D) and atomic force microscopy (AFM). QCM-D allowed following the adsorption kinetics while AFM measurements verified the morphology of lipid vesicles and isolated bilayer patches on the PEM cushions providing local topological images in terms of lateral organization. Additionally, polyelectrolyte cushions were characterized with ellipsometry to find thickness and swelling properties, and their roughness was determined using AFM. It has been demonstrated that the pH value and an addition of NaCl in the buffer solution as well as the type of the polyelectrolyte cushion influence the kinetics of bilayer formation and the quality of formed bilayer patches.
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Affiliation(s)
- Magdalena Wlodek
- Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences , 30-239 Cracow, Poland
| | | | - Marta Kolasinska-Sojka
- Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences , 30-239 Cracow, Poland
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6
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Wang L, Roth JS, Han X, Evans SD. Photosynthetic Proteins in Supported Lipid Bilayers: Towards a Biokleptic Approach for Energy Capture. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2015; 11:3306-3318. [PMID: 25727786 DOI: 10.1002/smll.201403469] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 01/11/2015] [Indexed: 06/04/2023]
Abstract
In nature, plants and some bacteria have evolved an ability to convert solar energy into chemical energy usable by the organism. This process involves several proteins and the creation of a chemical gradient across the cell membrane. To transfer this process to a laboratory environment, several conditions have to be met: i) proteins need to be reconstituted into a lipid membrane, ii) the proteins need to be correctly oriented and functional and, finally, iii) the lipid membrane should be capable of maintaining chemical and electrical gradients. Investigating the processes of photosynthesis and energy generation in vivo is a difficult task due to the complexity of the membrane and its associated proteins. Solid, supported lipid bilayers provide a good model system for the systematic investigation of the different components involved in the photosynthetic pathway. In this review, the progress made to date in the development of supported lipid bilayer systems suitable for the investigation of membrane proteins is described; in particular, there is a focus on those used for the reconstitution of proteins involved in light capture.
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Affiliation(s)
- Lei Wang
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
- State Key Laboratory of Urban Water Resource and Environment, School of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin, 150001, China
| | - Johannes S Roth
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - Xiaojun Han
- State Key Laboratory of Urban Water Resource and Environment, School of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin, 150001, China
| | - Stephen D Evans
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
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7
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Cheng N, Bao P, Evans SD, Leggett GJ, Armes SP. Facile Formation of Highly Mobile Supported Lipid Bilayers on Surface-Quaternized pH-Responsive Polymer Brushes. Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b00435] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- N. Cheng
- Department
of Chemistry, University of Sheffield, Sheffield S3 7HF, U.K
| | - P. Bao
- Molecular and Nanoscale Physics Group,
School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, U.K
| | - S. D. Evans
- Molecular and Nanoscale Physics Group,
School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, U.K
| | - G. J. Leggett
- Department
of Chemistry, University of Sheffield, Sheffield S3 7HF, U.K
| | - S. P. Armes
- Department
of Chemistry, University of Sheffield, Sheffield S3 7HF, U.K
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8
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Blakeston AC, Alswieleh AM, Heath GR, Roth JS, Bao P, Cheng N, Armes SP, Leggett GJ, Bushby RJ, Evans SD. New poly(amino acid methacrylate) brush supports the formation of well-defined lipid membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015. [PMID: 25746444 DOI: 10.1021/la504163s.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A novel poly(amino acid methacrylate) brush comprising zwitterionic cysteine groups (PCysMA) was utilized as a support for lipid bilayers. The polymer brush provides a 12-nm-thick cushion between the underlying hard support and the aqueous phase. At neutral pH, the zeta potential of the PCysMA brush was ∼-10 mV. Cationic vesicles containing >25% DOTAP were found to form a homogeneous lipid bilayer, as determined by a combination of surface analytical techniques. The lipid mobility as measured by FRAP (fluorescence recovery after photobleaching) gave diffusion coefficients of ∼1.5 μm(2) s(-1), which are comparable to those observed for lipid bilayers on glass substrates.
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Affiliation(s)
- Anita C Blakeston
- †Molecular and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Abdullah M Alswieleh
- ‡Department of Chemistry, University of Sheffield, Sheffield S3 7HF, United Kingdom
| | - George R Heath
- †Molecular and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Johannes S Roth
- †Molecular and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Peng Bao
- †Molecular and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Nan Cheng
- ‡Department of Chemistry, University of Sheffield, Sheffield S3 7HF, United Kingdom
| | - Steven P Armes
- ‡Department of Chemistry, University of Sheffield, Sheffield S3 7HF, United Kingdom
| | - Graham J Leggett
- ‡Department of Chemistry, University of Sheffield, Sheffield S3 7HF, United Kingdom
| | - Richard J Bushby
- †Molecular and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Stephen D Evans
- †Molecular and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
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9
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Blakeston A, Alswieleh AM, Heath GR, Roth JS, Bao P, Cheng N, Armes SP, Leggett GJ, Bushby RJ, Evans SD. New poly(amino acid methacrylate) brush supports the formation of well-defined lipid membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:3668-77. [PMID: 25746444 PMCID: PMC4444997 DOI: 10.1021/la504163s] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 01/29/2015] [Indexed: 05/19/2023]
Abstract
A novel poly(amino acid methacrylate) brush comprising zwitterionic cysteine groups (PCysMA) was utilized as a support for lipid bilayers. The polymer brush provides a 12-nm-thick cushion between the underlying hard support and the aqueous phase. At neutral pH, the zeta potential of the PCysMA brush was ∼-10 mV. Cationic vesicles containing >25% DOTAP were found to form a homogeneous lipid bilayer, as determined by a combination of surface analytical techniques. The lipid mobility as measured by FRAP (fluorescence recovery after photobleaching) gave diffusion coefficients of ∼1.5 μm(2) s(-1), which are comparable to those observed for lipid bilayers on glass substrates.
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Affiliation(s)
- Anita
C. Blakeston
- Molecular
and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United
Kingdom
| | | | - George R. Heath
- Molecular
and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United
Kingdom
| | - Johannes S. Roth
- Molecular
and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United
Kingdom
| | - Peng Bao
- Molecular
and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United
Kingdom
| | - Nan Cheng
- Department
of Chemistry, University of Sheffield, Sheffield S3 7HF, United Kingdom
| | - Steven P. Armes
- Department
of Chemistry, University of Sheffield, Sheffield S3 7HF, United Kingdom
| | - Graham J. Leggett
- Department
of Chemistry, University of Sheffield, Sheffield S3 7HF, United Kingdom
| | - Richard J. Bushby
- Molecular
and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United
Kingdom
| | - Stephen D. Evans
- Molecular
and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United
Kingdom
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10
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Saleem Q, Zhang Z, Petretic A, Gradinaru CC, Macdonald PM. Single lipid bilayer deposition on polymer surfaces using bicelles. Biomacromolecules 2015; 16:1032-9. [PMID: 25665160 DOI: 10.1021/acs.biomac.5b00042] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A lipid bilayer was deposited on a 3 μm diameter polystyrene (PS) bead via hydrophobic anchoring of bicelles containing oxyamine-bearing cholesteric moieties reacting with the aldehyde functionalized bead surface. Discoidal bicelles were formed by mixing dimyristoylphosphatidylcholine (DMPC), dihexanoylphosphatidylcholine (DHPC), dimyristoyltrimethylammonium propane (DMTAP), and the oxyamine-terminated cholesterol derivative, cholest-5-en-3β-oxy-oct-3,6-oxa-an-8-oxyamine (CHOLOA), in the molar ratio DMPC/DHCP/DMTAP/CHOLOA (1/0.5/0.01/0.05) in water. Upon exposure to aldehyde-bearing PS beads, a stable single lipid bilayer coating rapidly formed at the bead surface. Fluorescence recovery after photobleaching demonstrated that the deposited lipids fused into an encapsulating lipid bilayer. Electrospray ionization mass spectrometry showed that the short chain lipid DHPC was entirely absent from the PS adherent lipid coating. Fluorescence quenching measurements proved that the coating was a single lipid bilayer. The bicelle coating method is thus simple and robust, can be modified to include membrane-associated species, and can be adapted to coat any number of different surfaces.
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Affiliation(s)
- Qasim Saleem
- Departments of †Chemistry, ∥Physics, and ‡Chemical and Physical Sciences, University of Toronto Mississauga , 3359 Mississauga Road North, Mississauga, Ontario, Canada L5L 1C6
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11
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Sterling SM, Allgeyer ES, Fick J, Prudovsky I, Mason MD, Neivandt DJ. Phospholipid diffusion coefficients of cushioned model membranes determined via z-scan fluorescence correlation spectroscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:7966-74. [PMID: 23705855 PMCID: PMC3758428 DOI: 10.1021/la400768s] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Model cellular membranes enable the study of biological processes in a controlled environment and reduce the traditional challenges associated with live or fixed cell studies. However, model membrane systems based on the air/water or oil/solution interface do not allow for incorporation of transmembrane proteins or for the study of protein transport mechanisms. Conversely, a phospholipid bilayer deposited via the Langmuir-Blodgett/Langmuir-Schaefer method on a hydrogel layer is potentially an effective mimic of the cross section of a biological membrane and facilitates both protein incorporation and transport studies. Prior to application, however, such membranes must be fully characterized, particularly with respect to the phospholipid bilayer phase transition temperature. Here we present a detailed characterization of the phase transition temperature of the inner and outer leaflets of a chitosan supported model membrane system. Specifically, the lateral diffusion coefficient of each individual leaflet has been determined as a function of temperature. Measurements were performed utilizing z-scan fluorescence correlation spectroscopy (FCS), a technique that yields calibration-free diffusion information. Analysis via the method of Wawrezinieck and co-workers revealed that phospholipid diffusion changes from raftlike to free diffusion as the temperature is increased-an insight into the dynamic behavior of hydrogel supported membranes not previously reported.
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Affiliation(s)
- Sarah M. Sterling
- Department of Chemical and Biological Engineering, University of Maine, Orono, Maine 04469
- Graduate School of Biomedical Sciences, University of Maine, Orono, Maine 04469
| | - Edward S. Allgeyer
- Department of Physics and Astronomy, University of Maine, Orono, Maine 04469
| | - Jörg Fick
- Department of Chemical and Biological Engineering, University of Maine, Orono, Maine 04469
| | - Igor Prudovsky
- Graduate School of Biomedical Sciences, University of Maine, Orono, Maine 04469
- Maine Medical Center Research Institute, Scarborough, ME 04074
- Institute for Molecular Biophysics, Orono, Maine 04469
| | - Michael D. Mason
- Department of Chemical and Biological Engineering, University of Maine, Orono, Maine 04469
- Institute for Molecular Biophysics, Orono, Maine 04469
| | - David J. Neivandt
- Department of Chemical and Biological Engineering, University of Maine, Orono, Maine 04469
- Graduate School of Biomedical Sciences, University of Maine, Orono, Maine 04469
- Institute for Molecular Biophysics, Orono, Maine 04469
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12
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Influence of lipid membrane rigidity on properties of supporting polymer. Biophys J 2011; 101:128-33. [PMID: 21723822 DOI: 10.1016/j.bpj.2011.05.054] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Revised: 05/13/2011] [Accepted: 05/25/2011] [Indexed: 11/20/2022] Open
Abstract
Temperature-sensitive hydrogel polymers are utilized as responsive layers in various applications. Although the polymer's native characteristics have been studied extensively, details concerning its properties during interaction with biorelated structures are lacking. This work investigates the interaction between a thermoresponsive polymer cushion and different lipid membrane capping layers probed by neutron reflectometry. N-isopropylacrylamide copolymerized with methacroylbenzophenone first supported a lipid bilayer composed of 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE) and subsequently 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). The polymer-membrane systems were investigated above and below the polymer transition temperature (37 and 25°C). Although the same cushion supported each lipid membrane, the polymer hydration profile and thickness were markedly different for DPPE and DPPC systems. Because DPPE and DPPC have different bending rigidities, these results establish that the polymer-membrane interaction is critically mediated by the mechanics of the membrane, providing better insight into cell-hydrogel interactions.
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