The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Peter T C So - One of the best experts on this subject based on the ideXlab platform.
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two dimensional standing wave Total Internal Reflection fluorescence microscopy superresolution imaging of single molecular and biological specimens
Biophysical Journal, 2007Co-Authors: Euiheon Chung, Peter T C SoAbstract:The development of high resolution, high speed imaging techniques allows the study of dynamical processes in biological systems. Lateral resolution improvement of up to a factor of 2 has been achieved using structured illumination. In a Total Internal Reflection fluorescence microscope, an evanescence excitation field is formed as light is Total Internally reflected at an interface between a high and a low index medium. The <100 nm penetration depth of evanescence field ensures a thin excitation region resulting in low background fluorescence. We present even higher resolution wide-field biological imaging by use of standing wave Total Internal Reflection fluorescence (SW-TIRF). Evanescent standing wave (SW) illumination is used to generate a sinusoidal high spatial frequency fringe pattern on specimen for lateral resolution enhancement. To prevent thermal drift of the SW, novel detection and estimation of the SW phase with real-time feedback control is devised for the stabilization and control of the fringe phase. SW-TIRF is a wide-field superresolution technique with resolution better than a fifth of emission wavelength or ∼100 nm lateral resolution. We demonstrate the performance of the SW-TIRF microscopy using one- and two-directional SW illumination with a biological sample of cellular actin cytoskeleton of mouse fibroblast cells as well as single semiconductor nanocrystal molecules. The results confirm the superior resolution of SW-TIRF in addition to the merit of a high signal/background ratio from TIRF microscopy.
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extended resolution wide field optical imaging objective launched standing wave Total Internal Reflection fluorescence microscopy
Optics Letters, 2006Co-Authors: Euiheon Chung, Peter T C SoAbstract:Standing-wave Total-Internal-Reflection fluorescence (SW-TIRF) microscopy uses a super-diffraction-limited standing evanescent wave to extract the high-spatial-frequency content of an object through a diffraction-limited optical imaging system. The effective point-spread function is better than a quarter of the emission wavelength. With a 1.45 numerical aperture objective and 532 nm excitation wavelength, a Rayleigh resolution of approximately 100 nm can be achieved, which is better than twice the resolution of conventional TIRF microscopy. This first experimental realization of SW-TIRF in an objective-launched geometry demonstrates the potential for extended resolution imaging at high speed by using wide-field microscopy.
Dylan M Owen - One of the best experts on this subject based on the ideXlab platform.
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three dimensional Total Internal Reflection fluorescence nanoscopy with nanometric axial resolution by photometric localization of single molecules
Nature Communications, 2021Co-Authors: Alan M Szalai, Bruno Siarry, Jeronimo Lukin, David J Williamson, Nicolas Unsain, Alfredo Caceres, Mauricio Pilopais, Guillermo P Acuna, Damian Refojo, Dylan M OwenAbstract:Single-molecule localization microscopy enables far-field imaging with lateral resolution in the range of 10 to 20 nanometres, exploiting the fact that the centre position of a single-molecule’s image can be determined with much higher accuracy than the size of that image itself. However, attaining the same level of resolution in the axial (third) dimension remains challenging. Here, we present Supercritical Illumination Microscopy Photometric z-Localization with Enhanced Resolution (SIMPLER), a photometric method to decode the axial position of single molecules in a Total Internal Reflection fluorescence microscope. SIMPLER requires no hardware modification whatsoever to a conventional Total Internal Reflection fluorescence microscope and complements any 2D single-molecule localization microscopy method to deliver 3D images with nearly isotropic nanometric resolution. Performance examples include SIMPLER-direct stochastic optical reconstruction microscopy images of the nuclear pore complex with sub-20 nm axial localization precision and visualization of microtubule cross-sections through SIMPLER-DNA points accumulation for imaging in nanoscale topography with sub-10 nm axial localization precision. Achieving high axial resolution is challenging in single-molecule localization microscopy. Here, the authors present a photometric method to decode the axial position of single molecules in a Total Internal Reflection fluorescence microscope without hardware modification, and show nearly isotropic nanometric resolution.
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three dimensional Total Internal Reflection fluorescence nanoscopy with nanometric axial resolution by photometric localization of single molecules
Nature Communications, 2021Co-Authors: Alan M Szalai, Bruno Siarry, Jeronimo Lukin, David J Williamson, Nicolas Unsain, Alfredo Caceres, Mauricio Pilopais, Guillermo P Acuna, Damian Refojo, Dylan M OwenAbstract:Single-molecule localization microscopy enables far-field imaging with lateral resolution in the range of 10 to 20 nanometres, exploiting the fact that the centre position of a single-molecule's image can be determined with much higher accuracy than the size of that image itself. However, attaining the same level of resolution in the axial (third) dimension remains challenging. Here, we present Supercritical Illumination Microscopy Photometric z-Localization with Enhanced Resolution (SIMPLER), a photometric method to decode the axial position of single molecules in a Total Internal Reflection fluorescence microscope. SIMPLER requires no hardware modification whatsoever to a conventional Total Internal Reflection fluorescence microscope and complements any 2D single-molecule localization microscopy method to deliver 3D images with nearly isotropic nanometric resolution. Performance examples include SIMPLER-direct stochastic optical reconstruction microscopy images of the nuclear pore complex with sub-20 nm axial localization precision and visualization of microtubule cross-sections through SIMPLER-DNA points accumulation for imaging in nanoscale topography with sub-10 nm axial localization precision.
Herbert Schneckenburger - One of the best experts on this subject based on the ideXlab platform.
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Total Internal Reflection fluorescence microscopy technical innovations and novel applications
Current Opinion in Biotechnology, 2005Co-Authors: Herbert SchneckenburgerAbstract:Recent years have seen the introduction of novel techniques and applications of Total Internal Reflection fluorescence microscopy (TIRFM). Key technical achievements include miniaturization, enhanced depth resolution, reduction of detection volumes and the combination of TIRFM with other microscopic techniques. Novel applications have concentrated on single-molecule detection (e.g. of cellular receptors), imaging of exocytosis or endocytosis, measurements of adhesion foci of microtubules, and studies of the localization, activity and structural arrangement of specific ion channels. In addition to conventional fluorescent dyes, genetically engineered fluorescent proteins are increasingly being used to measure molecular conformations or intermolecular distances by fluorescence resonance energy transfer.
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variable angle Total Internal Reflection fluorescence microscopy va tirfm realization and application of a compact illumination device
Journal of Microscopy, 2003Co-Authors: Karl Stock, Reinhard Sailer, Wolfgang S L Strauss, M Lyttek, Rudolf Steiner, Herbert SchneckenburgerAbstract:A novel compact illumination device in variable-angle Total Internal Reflection fluorescence microscopy (VA-TIRFM) is described. This device replaces the standard condensor of an upright microscope. Light from different laser sources is delivered via a monomode fibre and focused onto identical parts of a sample under variable angles of Total Internal Reflection. Thus, fluorophores in close proximity to a cell-substrate interface are excited by an evanescent wave with variable penetration depth, and localized with high (nanometre) axial resolution. In addition to quantitative measurements in solution, fluorescence markers of the cytoplasm and the plasma membrane, i.e. calcein and laurdan, were examined using cultivated endothelial cells. Distances between the glass substrate and the plasma membrane were determined using the mathematical algorithm of a four-layer model, as well as a Gaussian-shaped intensity profile of the illumination spot on the samples. Distances between 0 and 30 nm in focal contacts and between 100 and 300 nm in other parts of the cell were thus determined. In addition to measurements of cell-substrate topology, the illumination device appears appropriate for numerous applications in which high axial resolution is required, e.g. experiments on endocytosis or exocytosis, as well as measurements of ion concentrations proximal to the plasma membrane. The compact illumination device is also suitable for combining TIRFM with further innovative techniques, e.g. time-resolved fluorescence spectroscopy, fluorescence lifetime imaging (FLIM) or fluorescence resonance energy transfer (FRET).
Euiheon Chung - One of the best experts on this subject based on the ideXlab platform.
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two dimensional standing wave Total Internal Reflection fluorescence microscopy superresolution imaging of single molecular and biological specimens
Biophysical Journal, 2007Co-Authors: Euiheon Chung, Peter T C SoAbstract:The development of high resolution, high speed imaging techniques allows the study of dynamical processes in biological systems. Lateral resolution improvement of up to a factor of 2 has been achieved using structured illumination. In a Total Internal Reflection fluorescence microscope, an evanescence excitation field is formed as light is Total Internally reflected at an interface between a high and a low index medium. The <100 nm penetration depth of evanescence field ensures a thin excitation region resulting in low background fluorescence. We present even higher resolution wide-field biological imaging by use of standing wave Total Internal Reflection fluorescence (SW-TIRF). Evanescent standing wave (SW) illumination is used to generate a sinusoidal high spatial frequency fringe pattern on specimen for lateral resolution enhancement. To prevent thermal drift of the SW, novel detection and estimation of the SW phase with real-time feedback control is devised for the stabilization and control of the fringe phase. SW-TIRF is a wide-field superresolution technique with resolution better than a fifth of emission wavelength or ∼100 nm lateral resolution. We demonstrate the performance of the SW-TIRF microscopy using one- and two-directional SW illumination with a biological sample of cellular actin cytoskeleton of mouse fibroblast cells as well as single semiconductor nanocrystal molecules. The results confirm the superior resolution of SW-TIRF in addition to the merit of a high signal/background ratio from TIRF microscopy.
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extended resolution wide field optical imaging objective launched standing wave Total Internal Reflection fluorescence microscopy
Optics Letters, 2006Co-Authors: Euiheon Chung, Peter T C SoAbstract:Standing-wave Total-Internal-Reflection fluorescence (SW-TIRF) microscopy uses a super-diffraction-limited standing evanescent wave to extract the high-spatial-frequency content of an object through a diffraction-limited optical imaging system. The effective point-spread function is better than a quarter of the emission wavelength. With a 1.45 numerical aperture objective and 532 nm excitation wavelength, a Rayleigh resolution of approximately 100 nm can be achieved, which is better than twice the resolution of conventional TIRF microscopy. This first experimental realization of SW-TIRF in an objective-launched geometry demonstrates the potential for extended resolution imaging at high speed by using wide-field microscopy.
Jefferson Y Han - One of the best experts on this subject based on the ideXlab platform.
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low cost multi touch sensing through frustrated Total Internal Reflection
User Interface Software and Technology, 2005Co-Authors: Jefferson Y HanAbstract:This paper describes a simple, inexpensive, and scalable technique for enabling high-resolution multi-touch sensing on rear-projected interactive surfaces based on frustrated Total Internal Reflection. We review previous applications of this phenomenon to sensing, provide implementation details, discuss results from our initial prototype, and outline future directions.
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multi touch sensing through frustrated Total Internal Reflection
International Conference on Computer Graphics and Interactive Techniques, 2005Co-Authors: Jefferson Y HanAbstract:High-resolution, scalable multi-touch sensing display systems and processes based on frustrated Total Internal Reflection employ an optical waveguide that receives light, such as infrared light, that undergoes Total Internal Reflection and an imaging sensor that detects light that escapes the optical waveguide caused by frustration of the Total Internal Reflection due to contact by a user. The optical waveguide when fitted with a compliant surface overlay provides superior sensing performance, as well as other benefits and features. The systems and processes described provide true multi-touch (multi-input) and high-spatial and temporal resolution capability due to the continuous imaging of the frustrated Total Internal Reflection that escapes the entire optical waveguide. Among other features and benefits, the systems and processes are scalable to large installations.
