1
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Yang B, Liu W, Chen X, Chen G, Zhu X. A novel multi-frame wavelet generative adversarial network for scattering reconstruction of structured illumination microscopy. Phys Med Biol 2023; 68:185016. [PMID: 37619594 DOI: 10.1088/1361-6560/acf3cb] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 08/24/2023] [Indexed: 08/26/2023]
Abstract
Objective. Structured illumination microscopy (SIM) is widely used in various fields of life science research. In clinical practice, it has low phototoxicity, fast imaging speed and no special fluorescent markers. However, SIM is still affected by the scattering medium of biological tissues, resulting in insufficient resolution of the obtained images, which limits the development of life sciences. A novel multi-frame wavelet generation adversarial network (MWGAN) is proposed to improve the scattering reconstruction capability of SIM.Approach. MWGAN is based on two components derived from the original image. A generative adversarial network constructed by wavelet transform is trained to reconstruct some complex details in the cell structure. Multi-frame adversarial network is used to obtain the inter-frame information of the image and use the complementary information of the before and after frames to improve the quality of the model reconstruction.Results. To demonstrate the robustness of MWGAN, multiple low-quality SIM image datasets are tested. Compared with the state-of-the-art methods, the proposed method achieves superior performance in both of the subjective and objective evaluation.Conclusion. MWGAN is effective for improving the clarity of SIM images. Meanwhile, the SIM images reconstructed by multiple frames improve the reconstruction quality of complex regions and allow clearer and dynamic observation of cellular functions.
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Affiliation(s)
- Bin Yang
- Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fujian Provincial Key Laboratory of Photonics Technology, Fujian Normal University, Fuzhou 350007, People's Republic of China
- Fujian Provincial Engineering Technology Research Center of Photoelectric Sensing Application, Fujian Normal University, Fuzhou 350007, People's Republic of China
| | - Weiping Liu
- Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fujian Provincial Key Laboratory of Photonics Technology, Fujian Normal University, Fuzhou 350007, People's Republic of China
- Fujian Provincial Engineering Technology Research Center of Photoelectric Sensing Application, Fujian Normal University, Fuzhou 350007, People's Republic of China
| | - Xinghong Chen
- Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fujian Provincial Key Laboratory of Photonics Technology, Fujian Normal University, Fuzhou 350007, People's Republic of China
- Fujian Provincial Engineering Technology Research Center of Photoelectric Sensing Application, Fujian Normal University, Fuzhou 350007, People's Republic of China
| | - Guannan Chen
- Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fujian Provincial Key Laboratory of Photonics Technology, Fujian Normal University, Fuzhou 350007, People's Republic of China
- Fujian Provincial Engineering Technology Research Center of Photoelectric Sensing Application, Fujian Normal University, Fuzhou 350007, People's Republic of China
| | - Xiaoqin Zhu
- Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fujian Provincial Key Laboratory of Photonics Technology, Fujian Normal University, Fuzhou 350007, People's Republic of China
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2
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Ortkrass H, Schürstedt J, Wiebusch G, Szafranska K, McCourt P, Huser T. High-speed TIRF and 2D super-resolution structured illumination microscopy with a large field of view based on fiber optic components. OPTICS EXPRESS 2023; 31:29156-29165. [PMID: 37710721 DOI: 10.1364/oe.495353] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 07/07/2023] [Indexed: 09/16/2023]
Abstract
Super-resolved structured illumination microscopy (SR-SIM) is among the most flexible, fast, and least perturbing fluorescence microscopy techniques capable of surpassing the optical diffraction limit. Current custom-built instruments are easily able to deliver two-fold resolution enhancement at video-rate frame rates, but the cost of the instruments is still relatively high, and the physical size of the instruments based on the implementation of their optics is still rather large. Here, we present our latest results towards realizing a new generation of compact, cost-efficient, and high-speed SR-SIM instruments. Tight integration of the fiber-based structured illumination microscope capable of multi-color 2D- and TIRF-SIM imaging, allows us to demonstrate SR-SIM with a field of view of up to 150 × 150 µm2 and imaging rates of up to 44 Hz while maintaining highest spatiotemporal resolution of less than 100 nm. We discuss the overall integration of optics, electronics, and software that allowed us to achieve this, and then present the fiberSIM imaging capabilities by visualizing the intracellular structure of rat liver sinusoidal endothelial cells, in particular by resolving the structure of their trans-cellular nanopores called fenestrations.
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3
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Hu K, Hu X, He T, Liu J, Liu S, Zhang J, Tan Y, Yang X, Wang H, Liang Y, Ye J. Structured Illumination Microscopy of Mitochondrial in Mouse Hepatocytes with an Improved Image Reconstruction Algorithm. MICROMACHINES 2023; 14:642. [PMID: 36985049 PMCID: PMC10055965 DOI: 10.3390/mi14030642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 03/04/2023] [Accepted: 03/10/2023] [Indexed: 06/18/2023]
Abstract
In this paper, a structured illumination microscopy (SIM) image reconstruction algorithm combined with notch function (N-SIM) is proposed. This method suppresses the defocus signal in the imaging process by processing the low-frequency signal of the image. The existing super-resolution image reconstruction algorithm produces streak artifacts caused by defocus signal. The experimental results show that the algorithm proposed in our study can well suppress the streak artifacts caused by defocused signals during the imaging process without losing the effective information of the image. The image reconstruction algorithm is used to analyze the mouse hepatocytes, and the image processing tool developed by MATLAB is applied to identify, detect and count the reconstructed images of mitochondria and lipid droplets, respectively. It is found that the mitochondrial activity in oxidative stress induced growth inhibitor 1 (OSGIN1) overexpressed mouse hepatocytes is higher than that in normal cells, and the interaction with lipid droplets is more obvious. This paper provides a reliable subcellular observation platform, which is very meaningful for biomedical work.
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Affiliation(s)
- Kai Hu
- Sino-German College of Intelligent Manufacturing, Shenzhen Technology University, Shenzhen 518118, China
- Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Provincial Higher Education Institute, Shenzhen Technology University, Shenzhen 518118, China
| | - Xuejuan Hu
- Sino-German College of Intelligent Manufacturing, Shenzhen Technology University, Shenzhen 518118, China
- Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Provincial Higher Education Institute, Shenzhen Technology University, Shenzhen 518118, China
- College of Physics and Photoelectric Engineering, Shenzhen University, Shenzhen 518060, China
| | - Ting He
- Sino-German College of Intelligent Manufacturing, Shenzhen Technology University, Shenzhen 518118, China
- Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Provincial Higher Education Institute, Shenzhen Technology University, Shenzhen 518118, China
- College of Physics and Photoelectric Engineering, Shenzhen University, Shenzhen 518060, China
| | - Jingxin Liu
- College of Pharmacy, Shenzhen Technology University, Shenzhen 518118, China
| | - Shiqian Liu
- Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Provincial Higher Education Institute, Shenzhen Technology University, Shenzhen 518118, China
| | - Jiaming Zhang
- Sino-German College of Intelligent Manufacturing, Shenzhen Technology University, Shenzhen 518118, China
- Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Provincial Higher Education Institute, Shenzhen Technology University, Shenzhen 518118, China
| | - Yadan Tan
- Sino-German College of Intelligent Manufacturing, Shenzhen Technology University, Shenzhen 518118, China
- Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Provincial Higher Education Institute, Shenzhen Technology University, Shenzhen 518118, China
- College of Physics Science and Technology, Guangxi Normal University, Guilin 541001, China
| | - Xiaokun Yang
- Sino-German College of Intelligent Manufacturing, Shenzhen Technology University, Shenzhen 518118, China
- Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Provincial Higher Education Institute, Shenzhen Technology University, Shenzhen 518118, China
| | - Hengliang Wang
- Sino-German College of Intelligent Manufacturing, Shenzhen Technology University, Shenzhen 518118, China
- Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Provincial Higher Education Institute, Shenzhen Technology University, Shenzhen 518118, China
| | - Yifei Liang
- Sino-German College of Intelligent Manufacturing, Shenzhen Technology University, Shenzhen 518118, China
- Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Provincial Higher Education Institute, Shenzhen Technology University, Shenzhen 518118, China
- College of Physics Science and Technology, Guangxi Normal University, Guilin 541001, China
| | - Jianze Ye
- Sino-German College of Intelligent Manufacturing, Shenzhen Technology University, Shenzhen 518118, China
- Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Provincial Higher Education Institute, Shenzhen Technology University, Shenzhen 518118, China
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4
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Ward EN, Hecker L, Christensen CN, Lamb JR, Lu M, Mascheroni L, Chung CW, Wang A, Rowlands CJ, Schierle GSK, Kaminski CF. Machine learning assisted interferometric structured illumination microscopy for dynamic biological imaging. Nat Commun 2022; 13:7836. [PMID: 36543776 PMCID: PMC9772218 DOI: 10.1038/s41467-022-35307-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 11/22/2022] [Indexed: 12/24/2022] Open
Abstract
Structured Illumination Microscopy, SIM, is one of the most powerful optical imaging methods available to visualize biological environments at subcellular resolution. Its limitations stem from a difficulty of imaging in multiple color channels at once, which reduces imaging speed. Furthermore, there is substantial experimental complexity in setting up SIM systems, preventing a widespread adoption. Here, we present Machine-learning Assisted, Interferometric Structured Illumination Microscopy, MAI-SIM, as an easy-to-implement method for live cell super-resolution imaging at high speed and in multiple colors. The instrument is based on an interferometer design in which illumination patterns are generated, rotated, and stepped in phase through movement of a single galvanometric mirror element. The design is robust, flexible, and works for all wavelengths. We complement the unique properties of the microscope with an open source machine-learning toolbox that permits real-time reconstructions to be performed, providing instant visualization of super-resolved images from live biological samples.
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Affiliation(s)
- Edward N. Ward
- grid.5335.00000000121885934Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
| | - Lisa Hecker
- grid.5335.00000000121885934Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
| | - Charles N. Christensen
- grid.5335.00000000121885934Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
| | - Jacob R. Lamb
- grid.5335.00000000121885934Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
| | - Meng Lu
- grid.5335.00000000121885934Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
| | - Luca Mascheroni
- grid.5335.00000000121885934Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
| | - Chyi Wei Chung
- grid.5335.00000000121885934Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
| | - Anna Wang
- grid.4991.50000 0004 1936 8948Department of Physics, Oxford University, Oxford, UK
| | - Christopher J. Rowlands
- grid.7445.20000 0001 2113 8111Department of Bioengineering, Imperial College London, London, UK
| | - Gabriele S. Kaminski Schierle
- grid.5335.00000000121885934Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
| | - Clemens F. Kaminski
- grid.5335.00000000121885934Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
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5
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Mahmud MS, Ruh D, Rohrbach A. ROCS microscopy with distinct zero-order blocking. OPTICS EXPRESS 2022; 30:44339-44349. [PMID: 36522860 DOI: 10.1364/oe.467966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 08/11/2022] [Indexed: 06/17/2023]
Abstract
Research in modern light microscopy continuously seeks to improve spatial and temporal resolution in combination with user-friendly, cost-effective imaging systems. Among different label-free imaging approaches, Rotating Coherent Scattering (ROCS) microscopy in darkfield mode achieves superior resolution and contrast without image reconstructions, which is especially helpful in life cell experiments. Here we demonstrate how to achieve 145 nm resolution with an amplitude transmission mask for spatial filtering. This mask blocks the reflected 0-th order focus at 12 distinct positions, thereby increasing the effective aperture for the light back-scattered from the object. We further show how angular correlation analysis between coherent raw images helps to estimate the information content from different illumination directions.
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6
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Tinning P, Donnachie M, Christopher J, Uttamchandani D, Bauer R. Miniaturized structured illumination microscopy using two 3-axis MEMS micromirrors. BIOMEDICAL OPTICS EXPRESS 2022; 13:6443-6456. [PMID: 36589569 PMCID: PMC9774859 DOI: 10.1364/boe.475811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 11/03/2022] [Accepted: 11/07/2022] [Indexed: 06/17/2023]
Abstract
We present the development and performance characterisation of a novel structured illumination microscope (SIM) in which the grating pattern is generated using two optical beams controlled via 2 micro-electro-mechanical system (MEMS) three-axis scanning micromirrors. The implementation of MEMS micromirrors to accurately and repeatably control angular, radial and phase positioning delivers flexible control of the fluorescence excitation illumination, with achromatic beam delivery through the same optical path, reduced spatial footprint and cost-efficient integration being further benefits. Our SIM architecture enables the direct implementation of multi-color imaging in a compact and adaptable package. The two-dimensional SIM system approach is enabled by a pair of 2 mm aperture electrostatically actuated three-axis micromirrors having static angular tilt motion along the x- and y-axes and static piston motion along the z-axis. This allows precise angular, radial and phase positioning of two optical beams, generating a fully controllable spatial interference pattern at the focal plane by adjusting the positions of the beam in the back-aperture of a microscope objective. This MEMS-SIM system was applied to fluorescent bead samples and cell specimens, and was able to obtain a variable lateral resolution improvement between 1.3 and 1.8 times the diffraction limited resolution.
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Affiliation(s)
- Peter Tinning
- Centre for Microsystems and Photonics, Department of Electronic and Electrical Engineering, University of Strathclyde, 99 George Street, Glasgow, G1 1RD, UK
- Currently with the Department of Physics,
University of Strathclyde, 107 Rotten Row,
Glasgow, G1 1XJ, UK
| | - Mark Donnachie
- Centre for Microsystems and Photonics, Department of Electronic and Electrical Engineering, University of Strathclyde, 99 George Street, Glasgow, G1 1RD, UK
| | - Jay Christopher
- Centre for Microsystems and Photonics, Department of Electronic and Electrical Engineering, University of Strathclyde, 99 George Street, Glasgow, G1 1RD, UK
| | - Deepak Uttamchandani
- Centre for Microsystems and Photonics, Department of Electronic and Electrical Engineering, University of Strathclyde, 99 George Street, Glasgow, G1 1RD, UK
| | - Ralf Bauer
- Centre for Microsystems and Photonics, Department of Electronic and Electrical Engineering, University of Strathclyde, 99 George Street, Glasgow, G1 1RD, UK
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7
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Unksov IN, Korosec CS, Surendiran P, Verardo D, Lyttleton R, Forde NR, Linke H. Through the Eyes of Creators: Observing Artificial Molecular Motors. ACS NANOSCIENCE AU 2022; 2:140-159. [PMID: 35726277 PMCID: PMC9204826 DOI: 10.1021/acsnanoscienceau.1c00041] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 12/20/2021] [Accepted: 12/20/2021] [Indexed: 11/28/2022]
Abstract
![]()
Inspired by molecular
motors in biology, there has been significant
progress in building artificial molecular motors, using a number of
quite distinct approaches. As the constructs become more sophisticated,
there is also an increasing need to directly observe the motion of
artificial motors at the nanoscale and to characterize their performance.
Here, we review the most used methods that tackle those tasks. We
aim to help experimentalists with an overview of the available tools
used for different types of synthetic motors and to choose the method
most suited for the size of a motor and the desired measurements,
such as the generated force or distances in the moving system. Furthermore,
for many envisioned applications of synthetic motors, it will be a
requirement to guide and control directed motions. We therefore also
provide a perspective on how motors can be observed on structures
that allow for directional guidance, such as nanowires and microchannels.
Thus, this Review facilitates the future research on synthetic molecular
motors, where observations at a single-motor level and a detailed
characterization of motion will promote applications.
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Affiliation(s)
- Ivan N. Unksov
- Solid State Physics and NanoLund, Lund University, Box 118, SE-221 00 Lund, Sweden
| | - Chapin S. Korosec
- Department of Physics, Simon Fraser University, V5A 1S6 Burnaby, British Columbia, Canada
| | | | - Damiano Verardo
- Solid State Physics and NanoLund, Lund University, Box 118, SE-221 00 Lund, Sweden
- AlignedBio AB, Medicon Village, Scheeletorget 1, 223 63 Lund, Sweden
| | - Roman Lyttleton
- Solid State Physics and NanoLund, Lund University, Box 118, SE-221 00 Lund, Sweden
| | - Nancy R. Forde
- Department of Physics, Simon Fraser University, V5A 1S6 Burnaby, British Columbia, Canada
| | - Heiner Linke
- Solid State Physics and NanoLund, Lund University, Box 118, SE-221 00 Lund, Sweden
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8
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100 Hz ROCS microscopy correlated with fluorescence reveals cellular dynamics on different spatiotemporal scales. Nat Commun 2022; 13:1758. [PMID: 35365619 PMCID: PMC8975811 DOI: 10.1038/s41467-022-29091-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 02/28/2022] [Indexed: 02/08/2023] Open
Abstract
Fluorescence techniques dominate the field of live-cell microscopy, but bleaching and motion blur from too long integration times limit dynamic investigations of small objects. High contrast, label-free life-cell imaging of thousands of acquisitions at 160 nm resolution and 100 Hz is possible by Rotating Coherent Scattering (ROCS) microscopy, where intensity speckle patterns from all azimuthal illumination directions are added up within 10 ms. In combination with fluorescence, we demonstrate the performance of improved Total Internal Reflection (TIR)-ROCS with variable illumination including timescale decomposition and activity mapping at five different examples: millisecond reorganization of macrophage actin cortex structures, fast degranulation and pore opening in mast cells, nanotube dynamics between cardiomyocytes and fibroblasts, thermal noise driven binding behavior of virus-sized particles at cells, and, bacterial lectin dynamics at the cortex of lung cells. Using analysis methods we present here, we decipher how motion blur hides cellular structures and how slow structure motions cover decisive fast motions.
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9
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Recent Progress in the Correlative Structured Illumination Microscopy. CHEMOSENSORS 2021. [DOI: 10.3390/chemosensors9120364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The super-resolution imaging technique of structured illumination microscopy (SIM) enables the mixing of high-frequency information into the optical transmission domain via light-source modulation, thus breaking the optical diffraction limit. Correlative SIM, which combines other techniques with SIM, offers more versatility or higher imaging resolution than traditional SIM. In this review, we first briefly introduce the imaging mechanism and development trends of conventional SIM. Then, the principles and recent developments of correlative SIM techniques are reviewed. Finally, the future development directions of SIM and its correlative microscopies are presented.
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10
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Valli J, Sanderson J. Super-Resolution Fluorescence Microscopy Methods for Assessing Mouse Biology. Curr Protoc 2021; 1:e224. [PMID: 34436832 DOI: 10.1002/cpz1.224] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Super-resolution (diffraction unlimited) microscopy was developed 15 years ago; the developers were awarded the Nobel Prize in Chemistry in recognition of their work in 2014. Super-resolution microscopy is increasingly being applied to diverse scientific fields, from single molecules to cell organelles, viruses, bacteria, plants, and animals, especially the mammalian model organism Mus musculus. In this review, we explain how super-resolution microscopy, along with fluorescence microscopy from which it grew, has aided the renaissance of the light microscope. We cover experiment planning and specimen preparation and explain structured illumination microscopy, super-resolution radial fluctuations, stimulated emission depletion microscopy, single-molecule localization microscopy, and super-resolution imaging by pixel reassignment. The final section of this review discusses the strengths and weaknesses of each super-resolution technique and how to choose the best approach for your research. © 2021 The Authors. Current Protocols published by Wiley Periodicals LLC.
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Affiliation(s)
- Jessica Valli
- Edinburgh Super Resolution Imaging Consortium (ESRIC), Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh, United Kingdom
| | - Jeremy Sanderson
- MRC Harwell Institute, Mammalian Genetics Unit, Harwell Campus, Oxfordshire, United Kingdom
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11
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Motionless Polarizing Structured Illumination Microscopy. SENSORS 2021; 21:s21082837. [PMID: 33920615 PMCID: PMC8073734 DOI: 10.3390/s21082837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/14/2021] [Accepted: 04/16/2021] [Indexed: 11/17/2022]
Abstract
In this investigation, we propose a motionless polarizing structured illumination microscopy as an axially sectioning and reflective-type device to measure the 3D surface profiles of specimens. Based on the spatial phase-shifting technique to obtain the visibility of the illumination pattern. Instead of using a grid, a Wollaston prism is used to generate the light pattern by the stable interference of two beams. As the polarization states of two beams are orthogonal with each other, a polarization pixelated CMOS camera can simultaneously obtain four phase-shifted patterns with the beams after passing through a quarter wave plate based on the spatial phase-shifting technique with polarization. In addition, a focus tunable lens is used to eliminate a mechanical moving part for the axial scanning of the specimen. In the experimental result, a step height sample and a concave mirror were measured with 0.05 µm and 0.2 mm repeatabilities of step height and the radius of curvature, respectively.
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Pospíšil J, Wiebusch G, Fliegel K, Klíma M, Huser T. Highly compact and cost-effective 2-beam super-resolution structured illumination microscope based on all-fiber optic components. OPTICS EXPRESS 2021; 29:11833-11844. [PMID: 33984956 DOI: 10.1364/oe.420592] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Current super-resolution structured illumination microscopes (SR-SIM) utilize relatively expensive electro-optic components and free-space optics, resulting in large setups. Moreover, high power laser sources are required to compensate for the losses associated with generating the illumination pattern by diffractive optics. Here, we present a highly compact and flexible 2D SR-SIM microscope based on all-fiber optic components (fiberSIM). Fiber-splitters deliver the laser light to the sample resulting in the interference illumination pattern. A microelectromechanical systems (MEMS) based fiber switch performs rapid pattern rotation. The pattern phase shift is achieved by the spatial displacement of one arm of the fiber interferometer using a piezoelectric crystal. Compared with existing methods, fiberSIM is highly compact and significantly reduces the SR-SIM component cost while achieving comparable results, thus providing a route to making SR-SIM technology accessible to even more laboratories in the life sciences.
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13
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Dersch S, Mehl J, Stuckenschneider L, Mayer B, Roth J, Rohrbach A, Graumann PL. Super-Resolution Microscopy and Single-Molecule Tracking Reveal Distinct Adaptive Dynamics of MreB and of Cell Wall-Synthesis Enzymes. Front Microbiol 2020; 11:1946. [PMID: 32973704 PMCID: PMC7468405 DOI: 10.3389/fmicb.2020.01946] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Accepted: 07/23/2020] [Indexed: 11/23/2022] Open
Abstract
The movement of filamentous, actin-like MreB and of enzymes synthesizing the bacterial cell wall has been proposed to be highly coordinated. We have investigated the motion of MreB and of RodA and PbpH cell wall synthesis enzymes at 500 ms and at 20 ms time scales, allowing us to compare the motion of entire MreB filaments as well as of single molecules with that of the two synthesis proteins. While all three proteins formed assemblies that move with very similar trajectory orientation and with similar velocities, their trajectory lengths differed considerably, with PbpH showing shortest and MreB longest trajectories. These experiments suggest different on/off rates for RodA and PbpH at the putative peptidoglycan-extending machinery (PGEM), and during interaction with MreB filaments. Single molecule tracking revealed distinct slow-moving and freely diffusing populations of PbpH and RodA, indicating that they change between free diffusion and slow motion, indicating a dynamic interaction with the PGEM complex. Dynamics of MreB molecules and the orientation and speed of filaments changed markedly after induction of salt stress, while there was little change for RodA and PbpH single molecule dynamics. During the stress adaptation phase, cells continued to grow and extended the cell wall, while MreB formed fewer and more static filaments. Our results show that cell wall synthesis during stress adaptation occurs in a mode involving adaptation of MreB dynamics, and indicate that Bacillus subtilis cell wall extension involves an interplay of enzymes with distinct binding kinetics to sites of active synthesis.
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Affiliation(s)
- Simon Dersch
- SYNMIKRO, LOEWE-Zentrum für Synthetische Mikrobiologie, Philipps-Univetsität Marburg, Marburg, Germany
- Fachbereich Chemie, Philipps-Univetsität Marburg, Marburg, Germany
| | - Johanna Mehl
- Laboratory for Bio- and Nano-Photonics, Department of Microsystems Engineering-IMTEK, BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Lisa Stuckenschneider
- SYNMIKRO, LOEWE-Zentrum für Synthetische Mikrobiologie, Philipps-Univetsität Marburg, Marburg, Germany
- Fachbereich Chemie, Philipps-Univetsität Marburg, Marburg, Germany
| | - Benjamin Mayer
- SYNMIKRO, LOEWE-Zentrum für Synthetische Mikrobiologie, Philipps-Univetsität Marburg, Marburg, Germany
- Fachbereich Chemie, Philipps-Univetsität Marburg, Marburg, Germany
| | - Julian Roth
- Laboratory for Bio- and Nano-Photonics, Department of Microsystems Engineering-IMTEK, BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Alexander Rohrbach
- Laboratory for Bio- and Nano-Photonics, Department of Microsystems Engineering-IMTEK, BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Peter L. Graumann
- SYNMIKRO, LOEWE-Zentrum für Synthetische Mikrobiologie, Philipps-Univetsität Marburg, Marburg, Germany
- Fachbereich Chemie, Philipps-Univetsität Marburg, Marburg, Germany
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