1
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Johansson TB, Davtyan R, Valderas-Gutiérrez J, Gonzalez Rodriguez A, Agnarsson B, Munita R, Fioretos T, Lilljebjörn H, Linke H, Höök F, Prinz CN. Sub-Nanomolar Detection of Oligonucleotides Using Molecular Beacons Immobilized on Lightguiding Nanowires. Nanomaterials (Basel) 2024; 14:453. [PMID: 38470783 DOI: 10.3390/nano14050453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 02/15/2024] [Accepted: 02/17/2024] [Indexed: 03/14/2024]
Abstract
The detection of oligonucleotides is a central step in many biomedical investigations. The most commonly used methods for detecting oligonucleotides often require concentration and amplification before detection. Therefore, developing detection methods with a direct read-out would be beneficial. Although commonly used for the detection of amplified oligonucleotides, fluorescent molecular beacons have been proposed for such direct detection. However, the reported limits of detection using molecular beacons are relatively high, ranging from 100 nM to a few µM, primarily limited by the beacon fluorescence background. In this study, we enhanced the relative signal contrast between hybridized and non-hybridized states of the beacons by immobilizing them on lightguiding nanowires. Upon hybridization to a complementary oligonucleotide, the fluorescence from the surface-bound beacon becomes coupled in the lightguiding nanowire core and is re-emitted at the nanowire tip in a narrower cone of light compared with the standard 4π emission. Prior knowledge of the nanowire positions allows for the continuous monitoring of fluorescence signals from each nanowire, which effectively facilitates the discrimination of signals arising from hybridization events against background signals. This resulted in improved signal-to-background and signal-to-noise ratios, which allowed for the direct detection of oligonucleotides at a concentration as low as 0.1 nM.
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Affiliation(s)
- Therese B Johansson
- Division of Solid State Physics, Lund University, 221 00 Lund, Sweden
- NanoLund, Lund University, 221 00 Lund, Sweden
| | - Rubina Davtyan
- Division of Solid State Physics, Lund University, 221 00 Lund, Sweden
- NanoLund, Lund University, 221 00 Lund, Sweden
| | - Julia Valderas-Gutiérrez
- Division of Solid State Physics, Lund University, 221 00 Lund, Sweden
- NanoLund, Lund University, 221 00 Lund, Sweden
| | | | - Björn Agnarsson
- Division of Nano and Biophysics, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Roberto Munita
- Division of Molecular Hematology, Department of Laboratory Medicine, Lund University, 221 00 Lund, Sweden
| | - Thoas Fioretos
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, 221 00 Lund, Sweden
| | - Henrik Lilljebjörn
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, 221 00 Lund, Sweden
| | - Heiner Linke
- Division of Solid State Physics, Lund University, 221 00 Lund, Sweden
- NanoLund, Lund University, 221 00 Lund, Sweden
| | - Fredrik Höök
- NanoLund, Lund University, 221 00 Lund, Sweden
- Division of Nano and Biophysics, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Christelle N Prinz
- Division of Solid State Physics, Lund University, 221 00 Lund, Sweden
- NanoLund, Lund University, 221 00 Lund, Sweden
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2
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Mapar M, Sjöberg M, Zhdanov VP, Agnarsson B, Höök F. Label-free quantification of protein binding to lipid vesicles using transparent waveguide evanescent-field scattering microscopy with liquid control. Biomed Opt Express 2023; 14:4003-4016. [PMID: 37799672 PMCID: PMC10549727 DOI: 10.1364/boe.490051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 06/16/2023] [Accepted: 06/18/2023] [Indexed: 10/07/2023]
Abstract
Recent innovations in microscopy techniques are paving the way for label-free studies of single nanoscopic biological entities such as viruses, lipid-nanoparticle drug carriers, and even proteins. One such technique is waveguide evanescent-field microscopy, which offers a relatively simple, yet sensitive, way of achieving label-free light scattering-based imaging of nanoparticles on surfaces. Herein, we extend the application of this technique by incorporating microfluidic liquid control and adapting the design for use with inverted microscopes by fabricating a waveguide on a transparent substrate. We furthermore formulate analytical models describing scattering and fluorescence intensities from single spherical and shell-like objects interacting with evanescent fields. The models are then applied to analyze scattering and fluorescence intensities from adsorbed polystyrene beads and to temporally resolve cholera-toxin B (CTB) binding to individual surface-immobilized glycosphingolipid GM1 containing vesicles. We also propose a self-consistent means to quantify the thickness of the CTB layer, revealing that protein-binding to individual vesicles can be characterized with sub-nm precision in a time-resolved manner.
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Affiliation(s)
- Mokhtar Mapar
- Division of Biological Physics, Department of Physics,
Chalmers University of Technology, SE-41296 Göteborg, Sweden
| | - Mattias Sjöberg
- Division of Biological Physics, Department of Physics,
Chalmers University of Technology, SE-41296 Göteborg, Sweden
- Nanolyze AB, BioVentureHub, Pepparedsleden 1, SE-43183 Göteborg, Sweden
| | - Vladimir P. Zhdanov
- Division of Biological Physics, Department of Physics,
Chalmers University of Technology, SE-41296 Göteborg, Sweden
- Boreskov Institute of Catalysis, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Björn Agnarsson
- Division of Biological Physics, Department of Physics,
Chalmers University of Technology, SE-41296 Göteborg, Sweden
- Nanolyze AB, BioVentureHub, Pepparedsleden 1, SE-43183 Göteborg, Sweden
| | - Fredrik Höök
- Division of Biological Physics, Department of Physics,
Chalmers University of Technology, SE-41296 Göteborg, Sweden
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3
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Armanious A, Gerelli Y, Micciulla S, Pace HP, Welbourn RJL, Sjöberg M, Agnarsson B, Höök F. Probing the Separation Distance between Biological Nanoparticles and Cell Membrane Mimics Using Neutron Reflectometry with Sub-Nanometer Accuracy. J Am Chem Soc 2022; 144:20726-20738. [DOI: 10.1021/jacs.2c08456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Antonius Armanious
- Department of Physics, Chalmers University of Technology, 41296Gothenburg, Sweden
| | - Yuri Gerelli
- Institut Max von Laue-Paul Langevin (ILL), 38042Grenoble, France
- Department of Life and Environmental Sciences, Università Politecnica delle Marche, 60131Ancona, Italy
| | | | - Hudson P. Pace
- Department of Physics, Chalmers University of Technology, 41296Gothenburg, Sweden
| | - Rebecca J. L. Welbourn
- ISIS Facility, STFC, Rutherford Appleton Laboratory, Chilton, Didcot, OxonOX11 0QX, United Kingdom
| | - Mattias Sjöberg
- Department of Physics, Chalmers University of Technology, 41296Gothenburg, Sweden
| | - Björn Agnarsson
- Department of Physics, Chalmers University of Technology, 41296Gothenburg, Sweden
| | - Fredrik Höök
- Department of Physics, Chalmers University of Technology, 41296Gothenburg, Sweden
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4
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Sjöberg M, Mapar M, Armanious A, Zhdanov VP, Agnarsson B, Höök F. Time-Resolved and Label-Free Evanescent Light-Scattering Microscopy for Mass Quantification of Protein Binding to Single Lipid Vesicles. Nano Lett 2021; 21:4622-4628. [PMID: 34003003 PMCID: PMC8289281 DOI: 10.1021/acs.nanolett.1c00644] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 05/05/2021] [Indexed: 06/12/2023]
Abstract
In-depth understanding of the intricate interactions between biomolecules and nanoparticles is hampered by a lack of analytical methods providing quantitative information about binding kinetics. Herein, we demonstrate how label-free evanescent light-scattering microscopy can be used to temporally resolve specific protein binding to individual surface-bound (∼100 nm) lipid vesicles. A theoretical model is proposed that translates protein-induced changes in light-scattering intensity into bound mass. Since the analysis is centered on individual lipid vesicles, the signal from nonspecific protein binding to the surrounding surface is completely avoided, offering a key advantage over conventional surface-based techniques. Further, by averaging the intensities from less than 2000 lipid vesicles, the sensitivity is shown to increase by orders of magnitude. Taken together, these features provide a new avenue in studies of protein-nanoparticle interaction, in general, and specifically in the context of nanoparticles in medical diagnostics and drug delivery.
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Affiliation(s)
- Mattias Sjöberg
- Division
of Nano and Biophysics, Department of Physics, Chalmers University of Technology, Gothenburg 41296, Sweden
| | - Mokhtar Mapar
- Division
of Nano and Biophysics, Department of Physics, Chalmers University of Technology, Gothenburg 41296, Sweden
| | - Antonius Armanious
- Division
of Nano and Biophysics, Department of Physics, Chalmers University of Technology, Gothenburg 41296, Sweden
| | - Vladimir P. Zhdanov
- Division
of Nano and Biophysics, Department of Physics, Chalmers University of Technology, Gothenburg 41296, Sweden
- Boreskov
Institute of Catalysis, Russian Academy
of Sciences, Novosibirsk 630090, Russia
| | - Björn Agnarsson
- Division
of Nano and Biophysics, Department of Physics, Chalmers University of Technology, Gothenburg 41296, Sweden
| | - Fredrik Höök
- Division
of Nano and Biophysics, Department of Physics, Chalmers University of Technology, Gothenburg 41296, Sweden
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5
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Verardo D, Liljedahl L, Richter C, Agnarsson B, Axelsson U, Prinz CN, Höök F, Borrebaeck CAK, Linke H. Fluorescence Signal Enhancement in Antibody Microarrays Using Lightguiding Nanowires. Nanomaterials (Basel) 2021; 11:nano11010227. [PMID: 33467141 PMCID: PMC7829981 DOI: 10.3390/nano11010227] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/13/2021] [Accepted: 01/14/2021] [Indexed: 01/13/2023]
Abstract
Fluorescence-based detection assays play an essential role in the life sciences and medicine. To offer better detection sensitivity and lower limits of detection (LOD), there is a growing need for novel platforms with an improved readout capacity. In this context, substrates containing semiconductor nanowires may offer significant advantages, due to their proven light-emission enhancing, waveguiding properties, and increased surface area. To demonstrate and evaluate the potential of such nanowires in the context of diagnostic assays, we have in this work adopted a well-established single-chain fragment antibody-based assay, based on a protocol previously designed for biomarker detection using planar microarrays, to freestanding, SiO2-coated gallium phosphide nanowires. The assay was used for the detection of protein biomarkers in highly complex human serum at high dilution. The signal quality was quantified and compared with results obtained on conventional flat silicon and plastic substrates used in the established microarray applications. Our results show that using the nanowire-sensor platform in combination with conventional readout methods, improves the signal intensity, contrast, and signal-to-noise by more than one order of magnitude compared to flat surfaces. The results confirm the potential of lightguiding nanowires for signal enhancement and their capacity to improve the LOD of standard diagnostic assays.
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Affiliation(s)
- Damiano Verardo
- NanoLund, Lund University, Box 118, 22100 Lund, Sweden; (D.V.); (C.N.P.); (F.H.)
- Solid State Physics, Lund University, Box 118, 22100 Lund, Sweden
- AlignedBio AB, Medicon Village, Scheeletorget 1, 223 63 Lund, Sweden
| | - Leena Liljedahl
- CREATE Health Translational Cancer Center, Department of Immunotechnology, Lund University, Medicon Village Bldg 406, 223 63 Lund, Sweden; (L.L.); (C.R.); (U.A.); (C.A.K.B.)
| | - Corinna Richter
- CREATE Health Translational Cancer Center, Department of Immunotechnology, Lund University, Medicon Village Bldg 406, 223 63 Lund, Sweden; (L.L.); (C.R.); (U.A.); (C.A.K.B.)
| | - Björn Agnarsson
- Department of Physics, Chalmers University of Technology, 41296 Gothenburg, Sweden;
| | - Ulrika Axelsson
- CREATE Health Translational Cancer Center, Department of Immunotechnology, Lund University, Medicon Village Bldg 406, 223 63 Lund, Sweden; (L.L.); (C.R.); (U.A.); (C.A.K.B.)
| | - Christelle N. Prinz
- NanoLund, Lund University, Box 118, 22100 Lund, Sweden; (D.V.); (C.N.P.); (F.H.)
- Solid State Physics, Lund University, Box 118, 22100 Lund, Sweden
| | - Fredrik Höök
- NanoLund, Lund University, Box 118, 22100 Lund, Sweden; (D.V.); (C.N.P.); (F.H.)
- Department of Physics, Chalmers University of Technology, 41296 Gothenburg, Sweden;
| | - Carl A. K. Borrebaeck
- CREATE Health Translational Cancer Center, Department of Immunotechnology, Lund University, Medicon Village Bldg 406, 223 63 Lund, Sweden; (L.L.); (C.R.); (U.A.); (C.A.K.B.)
| | - Heiner Linke
- NanoLund, Lund University, Box 118, 22100 Lund, Sweden; (D.V.); (C.N.P.); (F.H.)
- Solid State Physics, Lund University, Box 118, 22100 Lund, Sweden
- Correspondence:
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6
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Jõemetsa S, Joyce P, Lubart Q, Mapar M, Celauro E, Agnarsson B, Block S, Bally M, Esbjörner EK, Jeffries GDM, Höök F. Independent Size and Fluorescence Emission Determination of Individual Biological Nanoparticles Reveals that Lipophilic Dye Incorporation Does Not Scale with Particle Size. Langmuir 2020; 36:9693-9700. [PMID: 32787069 DOI: 10.1021/acs.langmuir.0c00941] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Advancements in nanoparticle characterization techniques are critical for improving the understanding of how biological nanoparticles (BNPs) contribute to different cellular processes, such as cellular communication, viral infection, as well as various drug-delivery applications. Since BNPs are intrinsically heterogeneous, there is a need for characterization methods that are capable of providing information about multiple parameters simultaneously, preferably at the single-nanoparticle level. In this work, fluorescence microscopy was combined with surface-based two-dimensional flow nanometry, allowing for simultaneous and independent determination of size and fluorescence emission of individual BNPs. In this way, the dependence of the fluorescence emission of the commonly used self-inserting lipophilic dye 3,3'-dioctadecyl-5,5'-di(4-sulfophenyl)oxacarbocyanine (SP-DiO) could successfully be correlated with nanoparticle size for different types of BNPs, including synthetic lipid vesicles, lipid vesicles derived from cellular membrane extracts, and extracellular vesicles derived from human SH-SY5Y cell cultures; all vesicles had a radius, r, of ∼50 nm and similar size distributions. The results demonstrate that the dependence of fluorescence emission of SP-DiO on nanoparticle size varies significantly between the different types of BNPs, with the expected dependence on membrane area, r2, being observed for synthetic lipid vesicles, while a significant weaker dependence on size was observed for BNPs with more complex composition. The latter observation is attributed to a size-dependent difference in membrane composition, which may influence either the optical properties of the dye and/or the insertion efficiency, indicating that the fluorescence emission of this type of self-inserting dye may not be reliable for determining size or size distribution of BNPs with complex lipid compositions.
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Affiliation(s)
- Silver Jõemetsa
- Department of Physics, Chalmers University of Technology, Fysikgränd 3, SE-41296 Göteborg, Sweden
| | - Paul Joyce
- Department of Physics, Chalmers University of Technology, Fysikgränd 3, SE-41296 Göteborg, Sweden
| | - Quentin Lubart
- Department of Physics, Chalmers University of Technology, Fysikgränd 3, SE-41296 Göteborg, Sweden
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE-41296 Göteborg, Sweden
| | - Mokhtar Mapar
- Department of Physics, Chalmers University of Technology, Fysikgränd 3, SE-41296 Göteborg, Sweden
| | - Emanuele Celauro
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE-41296 Göteborg, Sweden
| | - Björn Agnarsson
- Department of Physics, Chalmers University of Technology, Fysikgränd 3, SE-41296 Göteborg, Sweden
| | - Stephan Block
- Department of Chemistry and Biochemistry, Freie Universität Berlin, Takustrasse 3, 14195 Berlin, Germany
| | - Marta Bally
- Department of Physics, Chalmers University of Technology, Fysikgränd 3, SE-41296 Göteborg, Sweden
- Department of Clinical Microbiology & Wallenberg Centre for Molecular Medicine, Umeå University, NUS Målpunkt R, 901 85 Umeå, Sweden
| | - Elin K Esbjörner
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE-41296 Göteborg, Sweden
| | - Gavin D M Jeffries
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Kemivägen 10, SE-41296 Göteborg, Sweden
| | - Fredrik Höök
- Department of Physics, Chalmers University of Technology, Fysikgränd 3, SE-41296 Göteborg, Sweden
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7
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Verardo D, Agnarsson B, Zhdanov VP, Höök F, Linke H. Single-Molecule Detection with Lightguiding Nanowires: Determination of Protein Concentration and Diffusivity in Supported Lipid Bilayers. Nano Lett 2019; 19:6182-6191. [PMID: 31369284 DOI: 10.1021/acs.nanolett.9b02226] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Determining the surface concentration and diffusivity of cell-membrane-bound molecules is central to the understanding of numerous important biochemical processes taking place at cell membranes. Here we use the high aspect ratio and lightguiding properties of semiconductor nanowires (NWs) to detect the presence of single freely diffusing proteins bound to a lipid bilayer covering the NW surface. Simultaneous observation of light-emission dynamics of hundreds of individual NWs occurring on the time scale of only a few seconds is interpreted using analytical models and employed to determine both surface concentration and diffusivity of cholera toxin subunit B (CTxB) bound to GM1 gangliosides in supported lipid bilayer (SLB) at surface concentrations down to below one CTxB per μm2. In particular, a decrease in diffusivity was observed with increasing GM1 content in the SLB, suggesting increasing multivalent binding of CTxB to GM1. The lightguiding capability of the NWs makes the method compatible with conventional epifluorescence microscopy, and it is shown to work well for both photostable and photosensitive dyes. These features make the concept an interesting complement to existing techniques for studying the diffusivity of low-abundance cell-membrane-bound molecules, expanding the rapidly growing use of semiconductor NWs in various bioanalytical sensor applications and live cell studies.
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Affiliation(s)
- Damiano Verardo
- NanoLund and Solid State Physics , Lund University , 22100 Lund , Sweden
| | - Björn Agnarsson
- Department of Physics , Chalmers University of Technology , 41296 Göteborg , Sweden
| | - Vladimir P Zhdanov
- Department of Physics , Chalmers University of Technology , 41296 Göteborg , Sweden
- Boreskov Institute of Catalysis , Russian Academy of Sciences , Novosibirsk 630090 , Russia
| | - Fredrik Höök
- Department of Physics , Chalmers University of Technology , 41296 Göteborg , Sweden
| | - Heiner Linke
- NanoLund and Solid State Physics , Lund University , 22100 Lund , Sweden
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8
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Mapar M, Jõemetsa S, Pace H, Zhdanov VP, Agnarsson B, Höök F. Spatiotemporal Kinetics of Supported Lipid Bilayer Formation on Glass via Vesicle Adsorption and Rupture. J Phys Chem Lett 2018; 9:5143-5149. [PMID: 30137991 DOI: 10.1021/acs.jpclett.8b02092] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Supported lipid bilayers (SLBs) represent one of the most popular mimics of the cell membrane. Herein, we have used total internal reflection fluorescence microscopy for in-depth characterization of the vesicle-mediated SLB formation mechanism on a common silica-rich substrate, borosilicate glass. Fluorescently labeling a subset of vesicles allowed us to monitor the adsorption of individual labeled vesicles, resolve the onset of SLB formation from small seeds of SLB patches, and track their growth via SLB-edge-induced autocatalytic rupture of adsorbed vesicles. This made it possible to perform the first quantitative measurement of the SLB front velocity, which is shown to increase up to 1 order of magnitude with time. This effect can be classified as dramatic because in many other physical, chemical, or biological kinetic processes the front velocity is either constant or decreasing with time. The observation was successfully described with a theoretical model and Monte Carlo simulations implying rapid local diffusion of lipids upon vesicle rupture.
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Affiliation(s)
- Mokhtar Mapar
- Division of Biological Physics, Department of Physics , Chalmers University of Technology , 41296 Göteborg , Sweden
| | - Silver Jõemetsa
- Division of Biological Physics, Department of Physics , Chalmers University of Technology , 41296 Göteborg , Sweden
| | - Hudson Pace
- Division of Biological Physics, Department of Physics , Chalmers University of Technology , 41296 Göteborg , Sweden
| | - Vladimir P Zhdanov
- Division of Biological Physics, Department of Physics , Chalmers University of Technology , 41296 Göteborg , Sweden
- Boreskov Institute of Catalysis , Russian Academy of Sciences , Novosibirsk 630090 , Russia
| | - Björn Agnarsson
- Division of Biological Physics, Department of Physics , Chalmers University of Technology , 41296 Göteborg , Sweden
| | - Fredrik Höök
- Division of Biological Physics, Department of Physics , Chalmers University of Technology , 41296 Göteborg , Sweden
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9
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Rupert DLM, Mapar M, Shelke GV, Norling K, Elmeskog M, Lötvall JO, Block S, Bally M, Agnarsson B, Höök F. Effective Refractive Index and Lipid Content of Extracellular Vesicles Revealed Using Optical Waveguide Scattering and Fluorescence Microscopy. Langmuir 2018; 34:8522-8531. [PMID: 29923735 DOI: 10.1021/acs.langmuir.7b04214] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Extracellular vesicles (EVs) are generating a growing interest because of the key roles they play in various biological processes and because of their potential use as biomarkers in clinical diagnostics and as efficient carriers in drug-delivery and gene-therapy applications. Their full exploitation, however, depends critically on the possibility to classify them into different subpopulations, a task that in turn relies on efficient means to identify their unique biomolecular and physical signatures. Because of the large heterogeneity of EV samples, such information remains rather elusive, and there is accordingly a need for new and complementary characterization schemes that can help expand the library of distinct EV features. In this work, we used surface-sensitive waveguide scattering microscopy with single EV resolution to characterize two subsets of similarly sized EVs that were preseparated based on their difference in buoyant density. Unexpectedly, the scattering intensity distribution revealed that the scattering intensity of the high-density (HD) population was on an average a factor of three lower than that of the low-density (LD) population. By further labeling the EV samples with a self-inserting lipid-membrane dye, the scattering and fluorescence intensities from EVs could be simultaneously measured and correlated at the single-particle level. The labeled HD sample exhibited not only lower fluorescence and scattering intensities but also lower effective refractive index ( n ≈ 1.35) compared with the LD EVs ( n ≈ 1.38), indicating that both the lipid and protein contents were indeed lower in the HD EVs. Although separation in density gradients of similarly sized EVs is usually linked to differences in biomolecular content, we suggest based on these observations that the separation rather reflects the ability of the solute of the gradient to penetrate the lipid membrane enclosing the EVs, that is, the two gradient bands are more likely because of the differences in membrane permeability than to differences in biomolecular content of the EVs.
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Affiliation(s)
- Déborah L M Rupert
- Department of Physics , Chalmers University of Technology , 41296 Gothenburg , Sweden
| | - Mokhtar Mapar
- Department of Physics , Chalmers University of Technology , 41296 Gothenburg , Sweden
| | - Ganesh Vilas Shelke
- Krefting Research Centre, Department of Internal Medicine and Clinical Nutrition , University of Gothenburg , 40530 Gothenburg , Sweden
| | - Karin Norling
- Department of Physics , Chalmers University of Technology , 41296 Gothenburg , Sweden
| | - Mathias Elmeskog
- Department of Physics , Chalmers University of Technology , 41296 Gothenburg , Sweden
| | - Jan O Lötvall
- Krefting Research Centre, Department of Internal Medicine and Clinical Nutrition , University of Gothenburg , 40530 Gothenburg , Sweden
| | - Stephan Block
- Department of Physics , Chalmers University of Technology , 41296 Gothenburg , Sweden
| | - Marta Bally
- Department of Physics , Chalmers University of Technology , 41296 Gothenburg , Sweden
- Institut Curie, Centre de Recherche, CNRS, UMR168, Physico-Chimie Curie , Paris 75016 , France
| | - Björn Agnarsson
- Department of Physics , Chalmers University of Technology , 41296 Gothenburg , Sweden
| | - Fredrik Höök
- Department of Physics , Chalmers University of Technology , 41296 Gothenburg , Sweden
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10
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Armanious A, Gerelli Y, Agnarsson B, Pace H, Micciulla S, Schneck E, Höök F. A Holistic Approach to Study Interactions between Nanoparticles/Vesicles/Viruses and Supported Lipid Bilayers using QCM-D, Dual-Wavelength SPR, and Neutron Reflectometry. Biophys J 2018. [DOI: 10.1016/j.bpj.2017.11.1606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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11
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Lundgren A, Fast BJ, Block S, Agnarsson B, Reimhult E, Gunnarsson A, Höök F. Affinity Purification and Single-Molecule Analysis of Integral Membrane Proteins from Crude Cell-Membrane Preparations. Nano Lett 2018; 18:381-385. [PMID: 29231738 DOI: 10.1021/acs.nanolett.7b04227] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The function of integral membrane proteins is critically dependent on their naturally surrounding lipid membrane. Detergent-solubilized and purified membrane proteins are therefore often reconstituted into cell-membrane mimics and analyzed for their function with single-molecule microscopy. Expansion of this approach toward a broad range of pharmaceutically interesting drug targets and biomarkers however remains hampered by the fact that these proteins have low expression levels, and that detergent solubilization and reconstitution often cause protein conformational changes and loss of membrane-specific cofactors, which may impair protein function. To overcome this limitation, we here demonstrate how antibody-modified nanoparticles can be used to achieve affinity purification and enrichment of selected integral membrane proteins directly from cell membrane preparations. Nanoparticles were first bound to the ectodomain of β-secretase 1 (BACE1) contained in cell-derived membrane vesicles. In a subsequent step, these were merged into a continuous supported membrane in a microfluidic channel. Through the extended nanoparticle tag, a weak (∼fN) hydrodynamic force could be applied, inducing directed in-membrane movement of targeted BACE1 exclusively. This enabled selective thousand-fold enrichment of the targeted membrane protein while preserving a natural lipid environment. In addition, nanoparticle-targeting also enabled simultaneous tracking analysis of each individual manipulated protein, revealing how their mobility changed when moved from one lipid environment to another. We therefore believe this approach will be particularly useful for separation in-line with single-molecule analysis, eventually opening up for membrane-protein sorting devices analogous to fluorescence-activated cell sorting.
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Affiliation(s)
- Anders Lundgren
- Department of Physics, Chalmers University of Technology , 41296 Göteborg, Sweden
- Department of Nanobiotechnology, University of Natural Resources and Life Sciences , 1190 Vienna, Austria
| | - Björn Johansson Fast
- Department of Physics, Chalmers University of Technology , 41296 Göteborg, Sweden
| | - Stephan Block
- Department of Physics, Chalmers University of Technology , 41296 Göteborg, Sweden
| | - Björn Agnarsson
- Department of Physics, Chalmers University of Technology , 41296 Göteborg, Sweden
| | - Erik Reimhult
- Department of Nanobiotechnology, University of Natural Resources and Life Sciences , 1190 Vienna, Austria
| | - Anders Gunnarsson
- Discovery Sciences, Innovative Medicines and Early Development Biotech Unit, AstraZeneca , 43183 Mölndal, Sweden
| | - Fredrik Höök
- Department of Physics, Chalmers University of Technology , 41296 Göteborg, Sweden
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12
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Agnarsson B, Wayment-Steele HK, Höök F, Kunze A. Monitoring of single and double lipid membrane formation with high spatiotemporal resolution using evanescent light scattering microscopy. Nanoscale 2016; 8:19219-19223. [PMID: 27845799 DOI: 10.1039/c6nr06726c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Formation and quality of single solid supported lipid membranes and double lipid membranes were investigated with single vesicle resolution using label-free evanescence light scattering microscopy (EvSM). For the formation of double lipid membranes we made use of electrostatic interaction between charged lipids and oppositely charged cations.
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Affiliation(s)
- B Agnarsson
- Dept of Appl. Physics, Chalmers University of Technology, Göteborg, Sweden.
| | | | - F Höök
- Dept of Appl. Physics, Chalmers University of Technology, Göteborg, Sweden.
| | - A Kunze
- Dept of Appl. Physics, Chalmers University of Technology, Göteborg, Sweden. and Inst of Physical Chemistry, University of Göttingen, Göttingen, Germany
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13
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Lundgren A, Agnarsson B, Zirbs R, Zhdanov VP, Reimhult E, Höök F. Nonspecific Colloidal-Type Interaction Explains Size-Dependent Specific Binding of Membrane-Targeted Nanoparticles. ACS Nano 2016; 10:9974-9982. [PMID: 27783496 DOI: 10.1021/acsnano.6b04160] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Emerging biomedical applications such as molecular imaging and drug delivery often require directed binding of nanoparticles to cell-membrane receptors. The specific apparent affinity of such ligand-functionalized particles is size-dependent, an observation so far solely attributed to multivalent receptor-ligand interaction. We question the universality of this explanation by demonstrating that the binding kinetics also depends on weak, attractive colloidal-type interaction between nanoparticles and a lipid membrane. Applying label-free single-particle imaging, we correlate binding of nanoparticles targeted to a cell-mimetic lipid membrane with the distribution of nontargeted particles freely diffusing close to the membrane interface. This analysis shows that already a weak, kBT-scale attraction present between 50 nm gold nanoparticles and the membrane renders these particles an order of magnitude higher avidity compared to 20 nm particles. A stronger emphasis on nonspecific particle-membrane interaction might thus be required to accurately predict nanoparticle targeting and other similar processes such as cellular uptake of exosomes and viruses.
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Affiliation(s)
- Anders Lundgren
- Department of Physics, Chalmers University of Technology , Gothenburg 412 96, Sweden
- Department of Nanobiotechnology, University of Natural Resources and Life Sciences , Vienna 1190, Austria
| | - Björn Agnarsson
- Department of Physics, Chalmers University of Technology , Gothenburg 412 96, Sweden
| | - Ronald Zirbs
- Department of Nanobiotechnology, University of Natural Resources and Life Sciences , Vienna 1190, Austria
| | - Vladimir P Zhdanov
- Department of Physics, Chalmers University of Technology , Gothenburg 412 96, Sweden
- Boreskov Institute of Catalysis, Russian Academy of Sciences , Novosibirsk 630090, Russia
| | - Erik Reimhult
- Department of Nanobiotechnology, University of Natural Resources and Life Sciences , Vienna 1190, Austria
| | - Fredrik Höök
- Department of Physics, Chalmers University of Technology , Gothenburg 412 96, Sweden
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14
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Zhdanov VP, Agnarsson B, Höök F. Kinetics of enzyme-mediated hydrolysis of lipid vesicles. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2016.09.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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15
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Wayment-Steele HK, Jing Y, Swann MJ, Johnson LE, Agnarsson B, Svedhem S, Johal MS, Kunze A. Effects of Al(3+) on Phosphocholine and Phosphoglycerol Containing Solid Supported Lipid Bilayers. Langmuir 2016; 32:1771-1781. [PMID: 26783873 DOI: 10.1021/acs.langmuir.5b03999] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Aluminum has attracted great attention recently as it has been suggested by several studies to be associated with increased risks for Alzheimer's and Parkinson's disease. The toxicity of the trivalent ion is assumed to derive from structural changes induced in lipid bilayers upon binding, though the mechanism of this process is still not well understood. In the present study we elucidate the effect of Al(3+) on supported lipid bilayers (SLBs) using fluorescence microscopy, the quartz crystal microbalance with dissipation (QCM-D) technique, dual-polarization interferometry (DPI), and molecular dynamics (MD) simulations. Results from these techniques show that binding of Al(3+) to SLBs containing negatively charged and neutral phospholipids induces irreversible changes such as domain formation. The measured variations in SLB thickness, birefringence, and density indicate a phase transition from a disordered to a densely packed ordered phase.
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Affiliation(s)
- Hannah K Wayment-Steele
- Department of Chemistry, Pomona College , 645 North College Ave., Claremont, California 91711, United States
| | - Yujia Jing
- Department of Applied Physics, Chalmers University of Technology , 412 96 Göteborg, Sweden
| | - Marcus J Swann
- Swann Scientific Consulting Ltd., 110 Sandy Lane, Lymm, Cheshire, U.K
| | - Lewis E Johnson
- Department of Chemistry, Pomona College , 645 North College Ave., Claremont, California 91711, United States
- Department of Chemistry, University of Washington , 109 Bagley Hall, Seattle, Washington 98195, United States
| | - Björn Agnarsson
- Department of Applied Physics, Chalmers University of Technology , 412 96 Göteborg, Sweden
| | - Sofia Svedhem
- Department of Applied Physics, Chalmers University of Technology , 412 96 Göteborg, Sweden
| | - Malkiat S Johal
- Department of Chemistry, Pomona College , 645 North College Ave., Claremont, California 91711, United States
| | - Angelika Kunze
- Department of Applied Physics, Chalmers University of Technology , 412 96 Göteborg, Sweden
- Institute of Physical Chemistry, University of Göttingen , 37077 Göttingen, Germany
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16
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Agnarsson B, Lundgren A, Gunnarsson A, Rabe M, Kunze A, Mapar M, Simonsson L, Bally M, Zhdanov VP, Höök F. Evanescent Light-Scattering Microscopy for Label-Free Interfacial Imaging: From Single Sub-100 nm Vesicles to Live Cells. ACS Nano 2015; 9:11849-11862. [PMID: 26517791 DOI: 10.1021/acsnano.5b04168] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Advancement in the understanding of biomolecular interactions has benefited greatly from the development of surface-sensitive bioanalytical sensors. To further increase their broad impact, significant efforts are presently being made to enable label-free and specific biomolecule detection with high sensitivity, allowing for quantitative interpretation and general applicability at low cost. In this work, we have addressed this challenge by developing a waveguide chip consisting of a flat silica core embedded in a symmetric organic cladding with a refractive index matching that of water. This is shown to reduce stray light (background) scattering and thereby allow for label-free detection of faint objects, such as individual sub-20 nm gold nanoparticles as well as sub-100 nm lipid vesicles. Measurements and theoretical analysis revealed that light-scattering signals originating from single surface-bound lipid vesicles enable characterization of their sizes without employing fluorescent lipids as labels. The concept is also demonstrated for label-free measurements of protein binding to and enzymatic (phospholipase A2) digestion of individual lipid vesicles, enabling an analysis of the influence on the measured kinetics of the dye-labeling of lipids required in previous assays. Further, diffraction-limited imaging of cells (platelets) binding to a silica surface showed that distinct subcellular features could be visualized and temporally resolved during attachment, activation, and spreading. Taken together, these results underscore the versatility and general applicability of the method, which due to its simplicity and compatibility with conventional microscopy setups may reach a widespread in life science and beyond.
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Affiliation(s)
- Björn Agnarsson
- Division of Biological Physics, Department of Applied Physics, Chalmers University of Technology , SE-41296 Göteborg, Sweden
| | - Anders Lundgren
- Division of Biological Physics, Department of Applied Physics, Chalmers University of Technology , SE-41296 Göteborg, Sweden
| | - Anders Gunnarsson
- Division of Biological Physics, Department of Applied Physics, Chalmers University of Technology , SE-41296 Göteborg, Sweden
| | - Michael Rabe
- Division of Biological Physics, Department of Applied Physics, Chalmers University of Technology , SE-41296 Göteborg, Sweden
| | - Angelika Kunze
- Division of Biological Physics, Department of Applied Physics, Chalmers University of Technology , SE-41296 Göteborg, Sweden
- Institute of Physical Chemistry, University of Göttingen , D-37077 Göttingen, Germany
| | - Mokhtar Mapar
- Division of Biological Physics, Department of Applied Physics, Chalmers University of Technology , SE-41296 Göteborg, Sweden
| | - Lisa Simonsson
- Division of Biological Physics, Department of Applied Physics, Chalmers University of Technology , SE-41296 Göteborg, Sweden
| | - Marta Bally
- Division of Biological Physics, Department of Applied Physics, Chalmers University of Technology , SE-41296 Göteborg, Sweden
| | - Vladimir P Zhdanov
- Division of Biological Physics, Department of Applied Physics, Chalmers University of Technology , SE-41296 Göteborg, Sweden
- Boreskov Institute of Catalysis, Russian Academy of Sciences , Novosibirsk 630090, Russia
| | - Fredrik Höök
- Division of Biological Physics, Department of Applied Physics, Chalmers University of Technology , SE-41296 Göteborg, Sweden
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17
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Ahmadi S, Agnarsson B, Bidermane I, Wojek BM, Noël Q, Sun C, Göthelid M. Site-dependent charge transfer at the Pt(111)-ZnPc interface and the effect of iodine. J Chem Phys 2014; 140:174702. [DOI: 10.1063/1.4870762] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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18
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Sjövall P, Agnarsson B, Carlred L, Gunnarsson A, Höök F. Liposome binding for multiplexed biomolecule detection and imaging using ToF-SIMS. SURF INTERFACE ANAL 2014. [DOI: 10.1002/sia.5494] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- P. Sjövall
- Chemistry, Materials and Surfaces; SP Technical Research Institute of Sweden; P.O. Box 857 SE-50115 Borås Sweden
- Department of Applied Physics; Chalmers University of Technology; SE-41296 Gothenburg Sweden
| | - B. Agnarsson
- Department of Applied Physics; Chalmers University of Technology; SE-41296 Gothenburg Sweden
| | - L. Carlred
- Chemistry, Materials and Surfaces; SP Technical Research Institute of Sweden; P.O. Box 857 SE-50115 Borås Sweden
- Department of Applied Physics; Chalmers University of Technology; SE-41296 Gothenburg Sweden
| | - A. Gunnarsson
- Department of Applied Physics; Chalmers University of Technology; SE-41296 Gothenburg Sweden
| | - F. Höök
- Department of Applied Physics; Chalmers University of Technology; SE-41296 Gothenburg Sweden
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Leosson K, Shayestehaminzadeh S, Tryggvason TK, Kossoy A, Agnarsson B, Magnus F, Olafsson S, Gudmundsson JT, Magnusson EB, Shelykh IA. Comparing resonant photon tunneling via cavity modes and Tamm plasmon polariton modes in metal-coated Bragg mirrors. Opt Lett 2012; 37:4026-4028. [PMID: 23027267 DOI: 10.1364/ol.37.004026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Resonant photon tunneling was investigated experimentally in multilayer structures containing a high-contrast (TiO(2)/SiO(2)) Bragg mirror capped with a semitransparent gold film. Transmission via a fundamental cavity resonance was compared with transmission via the Tamm plasmon polariton resonance that appears at the interface between a metal film and a one-dimensional photonic bandgap structure. The Tamm-plasmon-mediated transmission exhibits a smaller dependence on the angle and polarization of the incident light for similar values of peak transmission, resonance wavelength, and finesse. Implications for transparent electrical contacts based on resonant tunneling structures are discussed.
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Affiliation(s)
- K Leosson
- Science Institute, University of Iceland, Dunhagi 3, IS-107 Reykjavik, Iceland.
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Agnarsson B, Jonsdottir AB, Arnfinnsdottir NB, Leosson K. On-chip modulation of evanescent illumination and live-cell imaging with polymer waveguides. Opt Express 2011; 19:22929-22935. [PMID: 22109170 DOI: 10.1364/oe.19.022929] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Imaging of live cells was carried out using evanescent-wave excitation on a polymer waveguide chip. Integrated waveguide-based interferometric light modulators were fabricated in order to demonstrate on-chip control of excitation light, e.g., for time-lapse fluorescence microscopy. When combined with a sensitive high-resolution imaging system, the integrated waveguide-excitation platform provides an ideal method of near-surface studies of live cells, where photobleaching and/or phototoxicity effects are of critical concern.
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Affiliation(s)
- Björn Agnarsson
- Department of Physics, Science Institute, University of Iceland, Dunhagi 3,IS-107 Reykjavik, Iceland
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Halldorsson J, Arnfinnsdottir NB, Jonsdottir AB, Agnarsson B, Leosson K. High index contrast polymer waveguide platform for integrated biophotonics. Opt Express 2010; 18:16217-16226. [PMID: 20721007 DOI: 10.1364/oe.18.016217] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We present detailed characterization of a unique high-index-contrast integrated optical polymer waveguide platform where the index of the cladding material is closely matched to that of water. Single-mode waveguides designed to operate across a large part of the visible spectrum have been fabricated and waveguide properties, including mode size, bend loss and evanescent coupling have been modeled using effective-index approximation, finite-element and finite-difference time domain methods. Integrated components such as directional couplers for wavelength splitting and ring resonators for refractive-index or temperature sensing have been modeled, fabricated and characterized. The waveguide platform described here is applicable to a wide range of biophotonic applications relying on evanescent-wave sensing or excitation, offering a high level of integration and functionality. The technology is biocompatible and suitable for wafer-level mass production.
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Affiliation(s)
- Jennifer Halldorsson
- Department of Physics, Science Institute, University of Iceland, Dunhagi 3,IS-107 Reykjavik, Iceland
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Agnarsson B, Ingthorsson S, Gudjonsson T, Leosson K. Evanescent-wave fluorescence microscopy using symmetric planar waveguides. Opt Express 2009; 17:5075-5082. [PMID: 19333269 DOI: 10.1364/oe.17.005075] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We describe a new evanescent-wave fluorescence excitation method, ideally suited for imaging of biological samples. The excitation light propagates in a planar optical waveguide, consisting of a thin waveguide core sandwiched between a sample in an aqueous solution and a polymer with a matching refractive index, forming a symmetric cladding environment. This configuration offers clear advantages over other waveguide-excitation methods, such as superior image quality, wide tunability of the evanescent field penetration depth and compatibility with optical fibers. The method is well suited for cell membrane imaging on cells in culture, including cell-cell and cell-matrix interaction, monitoring of surface binding events and similar applications involving aqueous solutions.
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Affiliation(s)
- Björn Agnarsson
- Department of Physics, Science Institute, University of Iceland, Reykjavik, Iceland
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