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Iga H, Shimizu T, Minoda H. Application of Hilbert-differential phase contrast to scanning transmission electron microscopy. Microscopy (Oxf) 2024; 73:414-421. [PMID: 38549508 DOI: 10.1093/jmicro/dfae015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 02/12/2024] [Accepted: 03/15/2024] [Indexed: 10/06/2024] Open
Abstract
We report a novel class of scanning transmission electron microscopy with Hilbert-differential phase contrast (HDP-STEM) that displays nanostructures of thin samples in a topographical manner. A semicircular π-phase plate (PP) was used as an optical device for manipulating electron waves in HDP-STEM. This is the different design from the Zernike PP used in our previous phase plate STEM (P-STEM), but both must be placed in the front focal plane of the condenser lens. HDP-STEM images of multiwalled carbon nanotubes showed higher contrast than those obtained by conventional bright-field STEM. As the PP of the HDP-STEM is nonsymmetrical, several different images were obtained by changing the detection conditions. A two-dimensional electron detector was also used to remove the scattering contrast component in the same way as with the Zernike PP and obtain an image containing only (differential) phase contrast.
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Affiliation(s)
- Haruka Iga
- Department of Applied Physics, Tokyo University of Agriculture and Technology, 2-24-16, Naka-cho, Koganei, Tokyo 184-8588, Japan
| | - Toshiki Shimizu
- Department of Applied Physics, Tokyo University of Agriculture and Technology, 2-24-16, Naka-cho, Koganei, Tokyo 184-8588, Japan
| | - Hiroki Minoda
- Department of Applied Physics, Tokyo University of Agriculture and Technology, 2-24-16, Naka-cho, Koganei, Tokyo 184-8588, Japan
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2
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Togashi M, Minoda H. First step toward complex observations by 4D-STEM with phase plate. Ultramicroscopy 2023; 249:113729. [PMID: 37028100 DOI: 10.1016/j.ultramic.2023.113729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 01/04/2023] [Accepted: 03/27/2023] [Indexed: 04/09/2023]
Abstract
Quantitative measurements by electron microscopy are becoming increasingly important because we are often concerned with establishing quantitative relationships between the properties and structures of materials. This paper presents a method to derive the scattering and phase contrast components from scanning transmission electron microscope (STEM) images using a phase plate and two-dimensional electron detector and to quantitatively evaluate the amount of phase modulation. The phase-contrast transfer function (PCTF) modifies the phase contrast because it is not unity over all spatial frequency regions; therefore, the amount of phase modulation observed in the image becomes smaller than the actual value. We applied a filter function to the Fourier transform of image to perform PCTF correction and evaluated the phase modulation of the electron waves, which was quantitatively agreement with the values expected from the thickness estimated from the scattering contrast within 20% error. So far, few quantitative discussions on phase modulation have been conducted. Although the accuracy needs to be improved, this method is the first step toward quantitative complex observations.
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Affiliation(s)
- Mayu Togashi
- Department of Applied Physics, Tokyo University of Agriculture and Technology, 2-24-16, Naka-cho, Koganei, Tokyo 184-8588, Japan
| | - Hiroki Minoda
- Department of Applied Physics, Tokyo University of Agriculture and Technology, 2-24-16, Naka-cho, Koganei, Tokyo 184-8588, Japan.
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3
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Malac M, Hettler S, Hayashida M, Kano E, Egerton RF, Beleggia M. Phase plates in the transmission electron microscope: operating principles and applications. Microscopy (Oxf) 2020; 70:75-115. [DOI: 10.1093/jmicro/dfaa070] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 10/30/2020] [Accepted: 12/11/2020] [Indexed: 01/19/2023] Open
Abstract
Abstract
In this paper, we review the current state of phase plate imaging in a transmission electron microscope. We focus especially on the hole-free phase plate design, also referred to as the Volta phase plate. We discuss the implementation, operating principles and applications of phase plate imaging. We provide an imaging theory that accounts for inelastic scattering in both the sample and in the hole-free phase plate.
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Affiliation(s)
- Marek Malac
- NRC-NANO, National Research Council, 11421 Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada
- Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Simon Hettler
- Laboratorio de Microscopías Avanzadas (LMA), Instituto de Nanociencia y Materiales de Aragon (INMA), Universidad de Zaragoza, Campus Río Ebro, 50018 Zaragoza, España
| | - Misa Hayashida
- NRC-NANO, National Research Council, 11421 Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada
| | - Emi Kano
- Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Ray F Egerton
- Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Marco Beleggia
- DTU Nanolab, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
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4
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Wang HW, Fan X. Challenges and opportunities in cryo-EM with phase plate. Curr Opin Struct Biol 2019; 58:175-182. [PMID: 31374473 DOI: 10.1016/j.sbi.2019.06.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 06/24/2019] [Accepted: 06/26/2019] [Indexed: 12/15/2022]
Abstract
Not long after the invention of transmission electron microscope (TEM), phase plate was proposed as a novel electron-optical apparatus at the back-focal plane of the objective lens to modulate the magnified specimen images with enhanced contrast, especially in cryo-electron microscopy (cryo-EM) application of biological specimens. In the past two decades, novel phase plates of different kinds were designed and fabricated for cryo-EM application. Some of them such as the Volta phase plate have already been proved very useful in single particle cryo-EM and cryo-electron tomography (cryo-ET) analysis. In this review, we discuss the current progress, challenges and opportunities of cryo-EM with phase plate.
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Affiliation(s)
- Hong-Wei Wang
- Ministry of Education Key Laboratory of Protein Sciences, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center of Biological Structures, School of Life Sciences, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China.
| | - Xiao Fan
- Ministry of Education Key Laboratory of Protein Sciences, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center of Biological Structures, School of Life Sciences, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China
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5
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Koeck PJB. Design of an electrostatic phase shifting device for biological transmission electron microscopy. Ultramicroscopy 2018; 187:107-112. [PMID: 29428429 DOI: 10.1016/j.ultramic.2018.01.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 01/07/2018] [Accepted: 01/17/2018] [Indexed: 10/18/2022]
Abstract
I suggest an electrostatic phase plate designed to broaden the contrast transfer function of a transmission electron microscope operated close to Scherzer defocus primarily in the low resolution direction. At higher defocus the low frequency behavior is equal to that close to Scherzer defocus, but CTF-correction becomes necessary to extend image interpretation to higher resolution. One simple realization of the phase plate consists of two ring shaped electrodes symmetrically surrounding the central beam. Since no physical components come into contact with the central beam and charge on the electrodes is controlled by an external voltage supply, problems with uncontrolled charging are expected to be reduced.
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Affiliation(s)
- Philip J B Koeck
- Royal Institute of Technology, School of Technology and Health, Sweden; Karolinska Institutet, Department of Biosciences and Nutrition, Novum, Huddinge 14183, Sweden.
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6
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Koeck PJ. Improved Hilbert phase contrast for transmission electron microscopy. Ultramicroscopy 2015; 154:37-41. [DOI: 10.1016/j.ultramic.2015.03.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 02/27/2015] [Accepted: 03/05/2015] [Indexed: 11/24/2022]
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7
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KOECK P, KARSHIKOFF A. Limitations of the linear and the projection approximations in three-dimensional transmission electron microscopy of fully hydrated proteins. J Microsc 2015; 259:197-209. [DOI: 10.1111/jmi.12253] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 03/09/2015] [Indexed: 11/29/2022]
Affiliation(s)
- P.J.B. KOECK
- Royal Institute of Technology; School of Technology and Health; Handen Sweden
- Department of Biosciences and Nutrition; Karolinska Institutet; Huddinge Sweden
| | - A. KARSHIKOFF
- Department of Biosciences and Nutrition; Karolinska Institutet; Huddinge Sweden
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8
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KOECK P. Improved Zernike-type phase contrast for transmission electron microscopy. J Microsc 2015; 259:74-8. [DOI: 10.1111/jmi.12250] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 02/24/2015] [Indexed: 11/29/2022]
Affiliation(s)
- P.J.B. KOECK
- Royal Institute of Technology, School of Technology and Health and Karolinska Institutet; Department of Biosciences and Nutrition at Novum; 14183 Huddinge Sweden
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9
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A nanocrystalline Hilbert phase-plate for phase-contrast transmission electron microscopy. Ultramicroscopy 2014; 139:29-37. [DOI: 10.1016/j.ultramic.2014.01.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 12/30/2013] [Accepted: 01/17/2014] [Indexed: 11/22/2022]
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10
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Glaeser RM. Invited review article: Methods for imaging weak-phase objects in electron microscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:111101. [PMID: 24289381 PMCID: PMC3855062 DOI: 10.1063/1.4830355] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 10/26/2013] [Indexed: 05/21/2023]
Abstract
Contrast has traditionally been produced in electron-microscopy of weak phase objects by simply defocusing the objective lens. There now is renewed interest, however, in using devices that apply a uniform quarter-wave phase shift to the scattered electrons relative to the unscattered beam, or that generate in-focus image contrast in some other way. Renewed activity in making an electron-optical equivalent of the familiar "phase-contrast" light microscope is based in part on the improved possibilities that are now available for device microfabrication. There is also a better understanding that it is important to take full advantage of contrast that can be had at low spatial frequency when imaging large, macromolecular objects. In addition, a number of conceptually new phase-plate designs have been proposed, thus increasing the number of options that are available for development. The advantages, disadvantages, and current status of each of these options is now compared and contrasted. Experimental results that are, indeed, superior to what can be accomplished with defocus-based phase contrast have been obtained recently with two different designs of phase-contrast aperture. Nevertheless, extensive work also has shown that fabrication of such devices is inconsistent, and that their working lifetime is short. The main limitation, in fact, appears to be electrostatic charging of any device that is placed into the electron diffraction pattern. The challenge in fabricating phase plates that are practical to use for routine work in electron microscopy thus may be more in the area of materials science than in the area of electron optics.
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Affiliation(s)
- Robert M Glaeser
- Life Sciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720, USA
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11
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Kuo PC, Chen IH, Chen CT, Lee KP, Chen CW, Lin CC, Chiu SWY, Hsieh YF, Wang YL, Shiue J. On-chip thin film Zernike phase plate for in-focus transmission electron microscopy imaging of organic materials. ACS NANO 2013; 7:465-470. [PMID: 23268656 DOI: 10.1021/nn304511p] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Transmission electron microscopy (TEM) is a powerful tool for imaging nanostructures, yet its capability is limited with respect to the imaging of organic materials because of the intrinsic low contrast problem. TEM phase plates have been in development for decades, yet a reliable phase plate technique has not been available because the performance of TEM phase plates deteriorates too quickly. Such an obstacle prohibits in-focus TEM phase imaging to be routinely achievable, thus limiting the technique being used in practical applications. Here we present an on-chip thin film Zernike phase plate which can effectively release charging and allow reliable in-focus TEM images of organic materials with enhanced contrast to be routinely obtained. With this stable system, we were able to characterize many polymer solar cell specimens and consequently identified and verified the existence of an unexpected nanoparticle phase. Furthermore, we were also able to observe the fine structures of an Escherichia coli specimen, without staining, using this on-chip thin film phase plate. Our system, which can be installed on a commercial TEM, opens up exciting possibilities for TEM to characterize organic materials.
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Affiliation(s)
- Pai-Chia Kuo
- Department of Materials Science and Engineering, National Taiwan University, Taipei 106, Taiwan
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12
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Barton B, Rhinow D, Walter A, Schröder R, Benner G, Majorovits E, Matijevic M, Niebel H, Müller H, Haider M, Lacher M, Schmitz S, Holik P, Kühlbrandt W. In-focus electron microscopy of frozen-hydrated biological samples with a Boersch phase plate. Ultramicroscopy 2011; 111:1696-705. [DOI: 10.1016/j.ultramic.2011.09.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 09/05/2011] [Accepted: 09/12/2011] [Indexed: 11/30/2022]
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13
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Li W, Han L. N-body Monte Carlo Simulation on High Contrast Biology Transmission Electron Microscope. J BIOL SYST 2011. [DOI: 10.1142/s021833901000369x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Inner and outer diameters of the phase plate limit the number of electrons passing and can affect the high-resolution information in the phase contrast image. A more practical column model including the First Condenser Lens CL1, Second Condenser Lens CL2, Mini-condenser Lens CM and Objective Lens(OL) was first built to obtain the beam performance at the upper surface of the phase plate. N -body Monte Carlo simulation was used to avoid error caused by big defocus from the Guassian image plane where a lens field exists. In building the motion equation in a practical field, second order finite element method and Hermite function interpolation were applied to get the axial field and its arbitrary order derivative. N motion equations were then solved by fifth-order Runge-Kutta algorithm and the performance of un-scattered and scattered electrons was given for a 200kV TEM. Results show that the beam spots are 2.7µm and 39µm for un-scattered and scattered electrons respectively. N -body Monte Carlo simulation can obtain both positions and velocities of un-scattered and scattered electrons at the arbitrary plane with aberrations being considered, which effectively avoids error from the defocus distance in classic aberration integrated methods.
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Affiliation(s)
- Wenping Li
- Key Laboratory of Micro-nano Measurement-Manipulation and Physics (Ministry of Education), School of Physics and Nuclear Energy Engineering, Beihang University, Beijing, 100191, People's Republic of China
| | - Li Han
- Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China
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14
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New and unconventional approaches for advancing resolution in biological transmission electron microscopy by improving macromolecular specimen preparation and preservation. Micron 2011; 42:141-51. [DOI: 10.1016/j.micron.2010.05.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2010] [Revised: 05/16/2010] [Accepted: 05/17/2010] [Indexed: 11/21/2022]
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15
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Marko M, Leith A, Hsieh C, Danev R. Retrofit implementation of Zernike phase plate imaging for cryo-TEM. J Struct Biol 2011; 174:400-12. [PMID: 21272647 DOI: 10.1016/j.jsb.2011.01.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Revised: 01/17/2011] [Accepted: 01/19/2011] [Indexed: 10/18/2022]
Abstract
In-focus phase-plate imaging is particularly beneficial for cryo-TEM because it offers a substantial overall increase in image contrast, without an electron dose penalty, and it simplifies image interpretation. We show how phase-plate cryo-TEM can be implemented with an appropriate existing TEM, and provide a basic practical introduction to use of thin-film (carbon) phase plates. We point out potential pitfalls of phase-plate operation, and discuss solutions. We provide information on evaluating a particular TEM for its suitability.
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Affiliation(s)
- Michael Marko
- Resource for Visualization of Biological Complexity, Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY 12201-0509, USA.
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16
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Alloyeau D, Ding B, Ramasse Q, Kisielowski C, Lee Z, Jeon KJ. Direct imaging and chemical analysis of unstained DNA origami performed with a transmission electron microscope. Chem Commun (Camb) 2011; 47:9375-7. [DOI: 10.1039/c1cc13654b] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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Sander B, Golas MM. Visualization of bionanostructures using transmission electron microscopical techniques. Microsc Res Tech 2010; 74:642-63. [DOI: 10.1002/jemt.20963] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2010] [Accepted: 10/01/2010] [Indexed: 11/10/2022]
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18
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Shiue J, Hung SK. A TEM phase plate loading system with loading monitoring and nano-positioning functions. Ultramicroscopy 2010; 110:1238-42. [DOI: 10.1016/j.ultramic.2010.05.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Revised: 04/28/2010] [Accepted: 05/11/2010] [Indexed: 11/29/2022]
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19
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Imaging of soft and hard materials using a Boersch phase plate in a transmission electron microscope. Ultramicroscopy 2010. [DOI: 10.1016/j.ultramic.2009.11.016] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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20
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Danev R, Kanamaru S, Marko M, Nagayama K. Zernike phase contrast cryo-electron tomography. J Struct Biol 2010; 171:174-81. [PMID: 20350600 DOI: 10.1016/j.jsb.2010.03.013] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2010] [Revised: 03/18/2010] [Accepted: 03/23/2010] [Indexed: 10/19/2022]
Abstract
Cryo-tomography in the electron microscope is unique in its ability to provide high-resolution, three-dimensional structural information about cells, organelles and macromolecules in a nearly native, frozen-hydrated state. However, the phase-contrast imaging method used in conventional cryo-electron tomography fails to faithfully represent the full range of structural features in such specimens. Only certain features are recorded with adequate contrast, and overall contrast is low. The recently developed Zernike phase contrast method has the potential to solve this problem, and here we apply it for the first time to cryo-electron tomography. The new method has uniform transfer characteristics for a wide range of spatial frequencies, leading to improved overall signal-to-noise ratio and raising the prospects of higher resolution and quantitative representation of specimen densities in the reconstructed tomograms.
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Affiliation(s)
- Radostin Danev
- Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787, Japan.
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21
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Kudryashev M, Lepper S, Baumeister W, Cyrklaff M, Frischknecht F. Geometric constrains for detecting short actin filaments by cryogenic electron tomography. PMC BIOPHYSICS 2010; 3:6. [PMID: 20214767 PMCID: PMC2844354 DOI: 10.1186/1757-5036-3-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2009] [Accepted: 03/05/2010] [Indexed: 01/30/2023]
Abstract
Polymerization of actin into filaments can push membranes forming extensions like filopodia or lamellipodia, which are important during processes such as cell motility and phagocytosis. Similarly, small organelles or pathogens can be moved by actin polymerization. Such actin filaments can be arranged in different patterns and are usually hundreds of nanometers in length as revealed by various electron microscopy approaches. Much shorter actin filaments are involved in the motility of apicomplexan parasites. However, these short filaments have to date not been visualized in intact cells. Here, we investigated Plasmodium sporozoites, the motile forms of the malaria parasite that are transmitted by the mosquito, using cryogenic electron tomography. We detected filopodia-like extensions of the plasma membrane and observed filamentous structures in the supra-alveolar space underneath the plasma membrane. However, these filaments could not be unambiguously assigned as actin filaments. In silico simulations of EM data collection and tomographic reconstruction identify the limits in revealing the filaments due to their length, concentration and orientation. PACS Codes: 87.64.Ee
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Affiliation(s)
- Mikhail Kudryashev
- Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany.
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Abstract
Phase plates are a new technique in the field of cryo-electron microscopy. They provide improved contrast and signal-to-noise ratio in images of radiation sensitive specimens. Thin film phase plates are being tested in biological applications and have demonstrated benefits for single particle analysis and cryo-tomography. There are still unsolved problems, such as reliability of manufacturing and deterioration of performance with time. Several other types of phase plates are currently under development and may become available for cryo-microscopy in near future. Presented is a short overview of the current state of the field as well as ideas for the future directions. Also included is a detailed description of the instrumentation requirements and the experimental procedures for phase plate application.
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Affiliation(s)
- Radostin Danev
- Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Okazaki, Japan
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