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https://www.readbyqxmd.com/read/28437075/fluorescent-photoswitchable-diarylethenes-for-biolabeling-and-single-molecule-localization-microscopies-with-optical-superresolution
#1
Benoit Roubinet, Michael Weber, Heydar Shojaei, Mark Bates, Mariano L Bossi, Vladimir N Belov, Masahiro Irie, Stefan W Hell
A modular assembly of water soluble diarylethenes (DAEs), applicable as bio-markers for optical nanoscopy, is reported. Reversibly photoswitchable 1,2-bis(2-alkyl-6-phenyl-1-benzothiophene-1,1-dioxide-3-yl)perfluorocyclopentenes possessing a fluorescent "closed" form were decorated with one or two methoxy group(s) attached to the para-position(s) of phenyl ring(s) and two, four or eight carboxylic acid groups. Antibody conjugates of these DAEs feature low aggregation, efficient photoswitching in aqueous buffers, specific staining of cellular structures and photophysical properties (high emission efficiencies and low cycloreversion quantum yields) enabling their application in superresolution microscopy...
April 24, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28428254/a-novel-physiological-role-for-arf1-in-the-formation-of-bi-directional-tubules-from-the-golgi
#2
Francesca Bottanelli, Nicole Kilian, Andreas M Ernst, Felix Rivera-Molina, Lena K Schroeder, Emil B Kromann, Mark D Lessard, Roman S Erdmann, Alanna Schepartz, David Baddeley, Joerg Bewersdorf, Derek Toomre, James E Rothman
Capitalizing on CRISPR/Cas9 gene editing techniques and super-resolution nanoscopy, we have explored the role of the small GTPase ARF1 in mediating transport steps at the Golgi. Surprisingly, beside its well-established role in generating COPI vesicles, we find that ARF1 is additionally involved in the formation of long (∼ 3 μm), thin (∼ 110 nm diameter) tubular carriers. The anterograde and retrograde tubular carriers are both largely free of the classical Golgi coat proteins Coatomer (COPI) and Clathrin...
April 20, 2017: Molecular Biology of the Cell
https://www.readbyqxmd.com/read/28417977/multicolour-nanoscopy-of-fixed-and-living-cells-with-a-single-sted-beam-and-hyperspectral-detection
#3
Franziska R Winter, Maria Loidolt, Volker Westphal, Alexey N Butkevich, Carola Gregor, Steffen J Sahl, Stefan W Hell
The extension of fluorescence nanoscopy to larger numbers of molecular species concurrently visualized by distinct markers is of great importance for advanced biological applications. To date, up to four markers had been distinguished in STED experiments featuring comparatively elaborate imaging schemes and optical setups, and exploiting various properties of the fluorophores. Here we present a simple yet versatile STED design for multicolour imaging below the diffraction limit. A hyperspectral detection arrangement (hyperSTED) collects the fluorescence in four spectral channels, allowing the separation of four markers with only one excitation wavelength and a single STED beam...
April 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28379846/sted-microscopy-visualizes-energy-deposition-of-single-ions-in-a-solid-state-detector-beyond-diffraction-limit
#4
M Niklas, M Henrich, O Jäkel, J Engelhardt, A Abdollahi, S Greilich
Fluorescent nuclear track detectors (FNTDs) allow for visualization of single-particle traversal in clinical ion beams. The point spread function of the confocal readout has so far hindered a more detailed characterization of the track spots-the ion's characteristic signature left in the FNTD. Here we report on the readout of the FNTD by optical nanoscopy, namely stimulated emission depletion microscopy. It was firstly possible to visualize the track spots of carbon ions and protons beyond the diffraction limit of conventional light microscopy with a resolving power of approximately 80 nm (confocal: 320 nm)...
April 5, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28355484/podosome-force-generation-machinery-a-local-balance-between-protrusion-at-the-core-and-traction-at-the-ring
#5
Anaïs Bouissou, Amsha Proag, Nicolas Bourg, Karine Pingris, Clément Cabriel, Stéphanie Balor, Thomas Mangeat, Christophe Thibault, Christophe Vieu, Guillaume Dupuis, Emmanuel Fort, Sandrine Lévêque-Fort, Isabelle Maridonneau-Parini, Renaud Poincloux
Determining how cells generate and transduce mechanical forces at the nanoscale is a major technical challenge for the understanding of numerous physiological and pathological processes. Podosomes are submicrometer cell structures with a columnar F-actin core surrounded by a ring of adhesion proteins, which possess the singular ability to protrude into and probe the extracellular matrix. Using protrusion force microscopy, we have previously shown that single podosomes produce local nanoscale protrusions on the extracellular environment...
April 4, 2017: ACS Nano
https://www.readbyqxmd.com/read/28317930/achromatic-light-patterning-and-improved-image-reconstruction-for-parallelized-resolft-nanoscopy
#6
Andriy Chmyrov, Marcel Leutenegger, Tim Grotjohann, Andreas Schönle, Jan Keller-Findeisen, Lars Kastrup, Stefan Jakobs, Gerald Donnert, Steffen J Sahl, Stefan W Hell
Fluorescence microscopy is rapidly turning into nanoscopy. Among the various nanoscopy methods, the STED/RESOLFT super-resolution family has recently been expanded to image even large fields of view within a few seconds. This advance relies on using light patterns featuring substantial arrays of intensity minima for discerning features by switching their fluorophores between 'on' and 'off' states of fluorescence. Here we show that splitting the light with a grating and recombining it in the focal plane of the objective lens renders arrays of minima with wavelength-independent periodicity...
March 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28287222/mapping-of-bernal-and-non-bernal-stacking-domains-in-bilayer-graphene-using-infrared-nanoscopy
#7
Gyouil Jeong, Boogeon Choi, Deok-Soo Kim, Seongjin Ahn, Baekwon Park, Jin Hyoun Kang, Hongki Min, Byung Hee Hong, Zee Hwan Kim
Bilayer graphene (BLG) shows great potential as a new material for opto-electronic devices because its bandgap can be controlled by varying the stacking orders, as well as by applying an external electric field. An imaging technique that can visualize and characterize various stacking domains in BLG may greatly help in fully utilizing such properties of BLG. Here we demonstrate that infrared (IR) scattering-type scanning near-field optical microscopy (sSNOM) can visualize Bernal and non-Bernal stacking domains of BLG, based on the stacking-specific inter- and intra-band optical conductivities...
March 13, 2017: Nanoscale
https://www.readbyqxmd.com/read/28262023/ground-state-depletion-nanoscopy-resolves-semiconductor-nanowire-barcode-segments-at-room-temperature
#8
Joanna Oracz, Karl Adolfsson, Volker Westphal, Czesław Radzewicz, Magnus T Borgström, Steffen J Sahl, Christelle N Prinz, Stefan W Hell
Nanowires hold great promise as tools for probing and interacting with various molecular and biological systems. Their unique geometrical properties (typically <100 nm in diameter and a few micrometers in length) enable minimally invasive interactions with living cells, so that electrical signals or forces can be monitored. All such experiments require in situ high-resolution imaging to provide context. While there is a clear need to extend visualization capabilities to the nanoscale, no suitable super-resolution far-field photoluminescence microscopy of extended semiconductor emitters has been described...
April 12, 2017: Nano Letters
https://www.readbyqxmd.com/read/28262022/stimulated-emission-depletion-microscopy
#9
Hans Blom, Jerker Widengren
Despite its short history, diffraction-unlimited fluorescence microscopy techniques have already made a substantial imprint in the biological sciences. In this review, we describe how stimulated emission depletion (STED) imaging originally evolved, how it compares to other optical super-resolution imaging techniques, and what advantages it provides compared to previous golden-standards for biological microscopy, such as diffraction-limited optical microscopy and electron microscopy. We outline the prerequisites for successful STED imaging experiments, emphasizing the equally critical roles of instrumentation, sample preparation, and photophysics, and describe major evolving strategies for how to push the borders of STED imaging even further in life science...
March 6, 2017: Chemical Reviews
https://www.readbyqxmd.com/read/28257567/hybrid-nanoscopy-of-hybrid-nanomaterials
#10
Patricia Bondia, Rocío Jurado, Santiago Casado, José M Domínguez-Vera, Natividad Gálvez, Cristina Flors
The combination of complementary techniques to characterize materials at the nanoscale is crucial to gain a more complete picture of their structure, a key step to design and fabricate new materials with improved properties and diverse functions. Here it is shown that correlative atomic force microscopy (AFM) and localization-based super-resolution microscopy is a useful tool that provides insight into the structure and emissive properties of fluorescent β-lactoglobulin (βLG) amyloid-like fibrils. These hybrid materials are made by functionalization of βLG with organic fluorophores and quantum dots, the latter being relevant for the production of 1D inorganic nanostructures templated by self-assembling peptides...
March 3, 2017: Small
https://www.readbyqxmd.com/read/28256876/fluorescent-nanowire-ring-illumination-for-wide-field-far-field-subdiffraction-imaging
#11
Xiaowei Liu, Cuifang Kuang, Xiang Hao, Chenlei Pang, Pengfei Xu, Haifeng Li, Ying Liu, Chao Yu, Yingke Xu, Di Nan, Weidong Shen, Yue Fang, Lenian He, Xu Liu, Qing Yang
Here we demonstrate an active method which pioneers in utilizing a combination of a spatial frequency shift and a Stokes frequency shift to enable wide-field far-field subdiffraction imaging. A fluorescent nanowire ring acts as a localized source and is combined with a film waveguide to produce omnidirectional illuminating evanescent waves. Benefitting from the high wave vector of illumination, the high spatial frequencies of an object can be shifted to the passband of a conventional imaging system, contributing subwavelength spatial information to the far-field image...
February 17, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28225761/amplified-stimulated-emission-in-upconversion-nanoparticles-for-super-resolution-nanoscopy
#12
Yujia Liu, Yiqing Lu, Xusan Yang, Xianlin Zheng, Shihui Wen, Fan Wang, Xavier Vidal, Jiangbo Zhao, Deming Liu, Zhiguang Zhou, Chenshuo Ma, Jiajia Zhou, James A Piper, Peng Xi, Dayong Jin
Lanthanide-doped glasses and crystals are attractive for laser applications because the metastable energy levels of the trivalent lanthanide ions facilitate the establishment of population inversion and amplified stimulated emission at relatively low pump power. At the nanometre scale, lanthanide-doped upconversion nanoparticles (UCNPs) can now be made with precisely controlled phase, dimension and doping level. When excited in the near-infrared, these UCNPs emit stable, bright visible luminescence at a variety of selectable wavelengths, with single-nanoparticle sensitivity, which makes them suitable for advanced luminescence microscopy applications...
February 22, 2017: Nature
https://www.readbyqxmd.com/read/28198876/precise-background-subtraction-in-stimulated-emission-double-depletion-nanoscopy
#13
Peng Gao, G Nienhaus
Low-resolution background in stimulated emission depletion (STED) nanoscopy can arise from incomplete depletion or re-excitation by the STED beam. We have recently introduced stimulated emission double depletion (STEDD), a technique to efficiently suppress this background. In STEDD, the conventional, doughnut-shaped STED pulse, which depletes excited fluorophores outside the center of the focal region, is followed by a second Gaussian STED pulse, which specifically depletes the central region. The background is removed by calculating a weighted difference of photon events collected before and after the second STED pulse...
February 15, 2017: Optics Letters
https://www.readbyqxmd.com/read/28193881/strong-signal-increase-in-sted-fluorescence-microscopy-by-imaging-regions-of-subdiffraction-extent
#14
Fabian Göttfert, Tino Pleiner, Jörn Heine, Volker Westphal, Dirk Görlich, Steffen J Sahl, Stefan W Hell
Photobleaching remains a limiting factor in superresolution fluorescence microscopy. This is particularly true for stimulated emission depletion (STED) and reversible saturable/switchable optical fluorescence transitions (RESOLFT) microscopy, where adjacent fluorescent molecules are distinguished by sequentially turning them off (or on) using a pattern of light formed as a doughnut or a standing wave. In sample regions where the pattern intensity reaches or exceeds a certain threshold, the molecules are essentially off (or on), whereas in areas where the intensity is lower, that is, around the intensity minima, the molecules remain in the initial state...
February 28, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28183938/flipping-nanoscopy-on-its-head
#15
Jie Xiao, Taekjip Ha
No abstract text is available yet for this article.
February 10, 2017: Science
https://www.readbyqxmd.com/read/28166407/optical-nanoscopy-of-high-tc-cuprate-nanoconstriction-devices-patterned-by-helium-ion-beams
#16
A Gozar, N E Litombe, Jennifer E Hoffman, I Božović
Helium ion beams (HIB) focused to subnanometer scales have emerged as powerful tools for high-resolution imaging as well as nanoscale lithography, ion milling, or deposition. Quantifying irradiation effects is an essential step toward reliable device fabrication, but most of the depth profiling information is provided by computer simulations rather than the experiment. Here, we demonstrate the use of atomic force microscopy (AFM) combined with scanning near-field optical microscopy (SNOM) to provide three-dimensional (3D) dielectric characterization of high-temperature superconductor devices fabricated by HIB...
March 8, 2017: Nano Letters
https://www.readbyqxmd.com/read/28155142/single-cell-cytochemistry-illustrated-by-the-demonstration-of-glucose-6-phosphate-dehydrogenase-deficiency-in-erythrocytes
#17
Anna L Peters, Cornelis J F van Noorden
Cytochemistry is the discipline that is applied to visualize specific molecules in individual cells and has become an essential tool in life sciences. Immunocytochemistry was developed in the sixties of last century and is the most frequently used cytochemical application. However, metabolic mapping is the oldest cytochemical approach to localize activity of specific enzymes, but in the last decades of the previous century and the first decade of the present century it almost became obsolete. The popularity of this approach revived in the past few years...
2017: Methods in Molecular Biology
https://www.readbyqxmd.com/read/28094292/chromatin-organization-revealed-by-nanostructure-of-irradiation-induced-%C3%AE-h2ax-53bp1-and-rad51-foci
#18
Judith Reindl, Stefanie Girst, Dietrich W M Walsh, Christoph Greubel, Benjamin Schwarz, Christian Siebenwirth, Guido A Drexler, Anna A Friedl, Günther Dollinger
The spatial distribution of DSB repair factors γH2AX, 53BP1 and Rad51 in ionizing radiation induced foci (IRIF) in HeLa cells using super resolution STED nanoscopy after low and high linear energy transfer (LET) irradiation was investigated. 53BP1 and γH2AX form IRIF with same mean size of (540 ± 40) nm after high LET irradiation while the size after low LET irradiation is significantly smaller. The IRIF of both repair factors show nanostructures with partial anti-correlation. These structures are related to domains formed within the chromatin territories marked by γH2AX while 53BP1 is mainly situated in the perichromatin region...
January 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28089515/navigation-through-the-plasma-membrane-molecular-landscape-shapes-random-organelle-movement
#19
Alison R Dun, Gabriel J Lord, Rhodri S Wilson, Deirdre M Kavanagh, Katarzyna I Cialowicz, Shuzo Sugita, Seungmee Park, Lei Yang, Annya M Smyth, Andreas Papadopulos, Colin Rickman, Rory R Duncan
Eukaryotic plasma membrane organization theory has long been controversial, in part due to a dearth of suitably high-resolution techniques to probe molecular architecture in situ and integrate information from diverse data streams [1]. Notably, clustered patterning of membrane proteins is a commonly conserved feature across diverse protein families (reviewed in [2]), including the SNAREs [3], SM proteins [4, 5], ion channels [6, 7], and receptors (e.g., [8]). Much effort has gone into analyzing the behavior of secretory organelles [9-13], and understanding the relationship between the membrane and proximal organelles [4, 5, 12, 14] is an essential goal for cell biology as broad concepts or rules may be established...
February 6, 2017: Current Biology: CB
https://www.readbyqxmd.com/read/28080023/microbial-nanoscopy-breakthroughs-challenges-and-opportunities
#20
Yves F Dufrêne
Studying the structure, properties, and interactions of microbial cells is key to understanding the functions of the microbiome. Recent advances in nanotechnology have offered new tools to probe microbes at the single-molecule and single-cell levels. In this issue of ACS Nano, Kumar et al. present an atomic force microscopy method that is capable of imaging the nanoscale organization of bacterial proteins in native, curved membranes. This study represents an important step forward in the development of nanoscopy techniques for analyzing biological systems with large curvature and vertical dimensions, such as membrane vesicles and bacterial cells...
January 12, 2017: ACS Nano
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