The Experts below are selected from a list of 8565 Experts worldwide ranked by ideXlab platform
Wei Min - One of the best experts on this subject based on the ideXlab platform.
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Biological imaging of chemical bonds by Stimulated Raman Scattering microscopy
Nature Methods, 2019Co-Authors: Lixue Shi, Wei MinAbstract:This Perspective summarizes advances in Stimulated Raman spectroscopy (SRS) instruments and probes, and highlights biological discoveries made with these technologies. All molecules consist of chemical bonds, and much can be learned from mapping the spatiotemporal dynamics of these bonds. Since its invention a decade ago, Stimulated Raman Scattering (SRS) microscopy has become a powerful modality for imaging chemical bonds with high sensitivity, resolution, speed and specificity. We introduce the fundamentals of SRS microscopy and review innovations in SRS microscopes and imaging probes. We highlight examples of exciting biological applications, and share our vision for potential future breakthroughs for this technology.
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live cell imaging analysis of antimycin type depsipeptides via bioorthogonal Stimulated Raman Scattering microscopy
bioRxiv, 2019Co-Authors: J Seidel, Wei Min, Yupeng Miao, William B Porterfield, Wenqing Cai, Xuejun Zhu, Seong Jong Kim, S Bhattaraikline, Weiguo ZhangAbstract:Abstract Small-molecule natural products have been an essential source of pharmaceuticals to treat human diseases, but very little is known about their behavior inside dynamic, living human cells. Here, we demonstrate the first structure-activity-distribution study of complex natural products, the anti-cancer antimycin-type depsipeptides, using the emerging bioorthogonal Stimulated Raman Scattering (SRS) Microscopy. Our results show that the intracellular enrichment and distribution of these compounds are driven by their potency and specific protein targets, as well as the lipophilic nature of compounds.
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electronic resonant Stimulated Raman Scattering micro spectroscopy
Journal of Physical Chemistry B, 2018Co-Authors: Lixue Shi, Yihui Shen, Lu Wei, Hanqing Xiong, Rong Long, Wei MinAbstract:Recently we have reported electronic pre-resonance Stimulated Raman Scattering (epr-SRS) microscopy as a powerful technique for super-multiplex imaging (Wei, L.; Nature 2017, 544, 465−470). However...
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operando and three dimensional visualization of anion depletion and lithium growth by Stimulated Raman Scattering microscopy
Nature Communications, 2018Co-Authors: Qian Cheng, Wei Min, Lu Wei, Zhe Liu, Zhe Sang, Bin Zhu, Meijie Chen, Yupeng Miao, Long Qing Chen, Yuan YangAbstract:Visualization of ion transport in electrolytes provides fundamental understandings of electrolyte dynamics and electrolyte-electrode interactions. However, this is challenging because existing techniques are hard to capture low ionic concentrations and fast electrolyte dynamics. Here we show that Stimulated Raman Scattering microscopy offers required resolutions to address a long-lasting question: how does the lithium-ion concentration correlate to uneven lithium deposition? In this study, anions are used to represent lithium ions since their concentrations should not deviate for more than 0.1 mM, even near nanoelectrodes. A three-stage lithium deposition process is uncovered, corresponding to no depletion, partial depletion, and full depletion of lithium ions. Further analysis reveals a feedback mechanism between the lithium dendrite growth and heterogeneity of local ionic concentration, which can be suppressed by artificial solid electrolyte interphase. This study shows that Stimulated Raman Scattering microscopy is a powerful tool for the materials and energy field.
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Stimulated Raman Scattering of polymer nanoparticles for multiplexed live cell imaging
Chemical Communications, 2017Co-Authors: Spencer D Brucks, Tristan H Lambert, Luis M Campos, Wei MinAbstract:A novel nanoparticle-based imaging strategy is introduced that couples biocompatible organic nanoparticles and Stimulated Raman Scattering (SRS) microscopy. Polymer nanoparticles with vibrational labels incorporated were readily prepared for multi-color SRS imaging with excellent photo-stability. The Raman-active polymer dots are nontoxic, rapidly enter various cell types, and are applied in multiplexed cell-type sorting.
Dario Polli - One of the best experts on this subject based on the ideXlab platform.
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in line balanced detection Stimulated Raman Scattering microscopy
Scientific Reports, 2017Co-Authors: Francesco Crisafi, M Marangoni, Vikas Kumar, Dario Polli, Giulio Cerullo, T ScopignoAbstract:We introduce a novel configuration for Stimulated Raman Scattering (SRS) microscopy, called In-line Balanced Detection (IBD), which employs a birefringent plate to generate a time-delayed polarization-multiplexed collinear replica of the probe, acting as a reference. Probe and reference cross the sample at the same position, thus maintaining their balance during image acquisition. IBD can be implemented in any conventional SRS setup, by adding a few simple elements, bringing its sensitivity close to the shot-noise limit even with a noisy laser. We tested IBD with a fiber-format laser system and observed signal-to-noise ratio improvement by up to 30 dB.
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broadband Stimulated Raman Scattering spectroscopy by a photonic time stretcher
Optics Express, 2016Co-Authors: Francesco Saltarelli, Vikas Kumar, Francesco Crisafi, Giulio Cerullo, Daniele Viola, Fabrizio Preda, Dario PolliAbstract:Stimulated Raman Scattering spectroscopy is a powerful technique for label-free molecular identification, but its broadband implementation is technically challenging. We introduce and experimentally demonstrate a novel approach based on photonic time stretch. The broadband femtosecond Stokes pulse, after interacting with the sample, is stretched by a telecom fiber to ≈15ns, mapping its spectrum in time. The signal is sampled through a fast analog-to-digital converter, providing single-shot spectra at 80-kHz rate. We demonstrate ≈10−5 sensitivity over ≈500cm−1 in the C-H region. Our results pave the way to high-speed broadband vibrational imaging for materials science and biophotonics.
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broadband Stimulated Raman Scattering with fourier transform detection
Optics Express, 2015Co-Authors: Julien Rehault, M Marangoni, Vikas Kumar, Francesco Crisafi, Gustavo Ciardi, Giulio Cerullo, Dario PolliAbstract:We propose a new approach to broadband Stimulated Raman Scattering (SRS) spectroscopy and microscopy based on time-domain Fourier transform (FT) detection of the Stimulated Raman gain (SRG) spectrum. We generate two phase-locked replicas of the Stokes pulse after the sample using a passive birefringent interferometer and measure by the FT technique both the Stokes and the SRG spectra. Our approach blends the very high sensitivity of single-channel lock-in balanced detection with the spectral coverage and resolution afforded by FT spectroscopy. We demonstrate our method by measuring the SRG spectra of different compounds and performing broadband SRS imaging on inorganic blends.
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fiber format Stimulated Raman Scattering microscopy from a single laser oscillator
Optics Letters, 2010Co-Authors: Alessio Gambetta, Vikas Kumar, Giulia Grancini, Dario Polli, Roberta Ramponi, G Cerullo, M MarangoniAbstract:A highly simplified architecture for Stimulated-Raman-Scattering microscopy is demonstrated, where multiple tunable narrowband picosecond pulses are generated by spectral compression of femtosecond pulses emitted by a single compact Er-fiber oscillator. The system provides high sensitivity (2×10−7) and spectral resolution (sub-15 cm−1), and it offers an unprecedented flexibility for multicolor imaging.
Chee Wei Wong - One of the best experts on this subject based on the ideXlab platform.
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Enhanced Stimulated Raman Scattering in slow-light photonic crystal waveguides
2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference, 2006Co-Authors: James F. Mcmillan, Nicolae C. Panoiu, Richard M. Osgood, Chee Wei WongAbstract:We investigate slow-light enhancement of Stimulated Raman Scattering in monolithic silicon photonic crystal defect waveguides. The applied Bloch-Floquet formalism demonstrates remarkable gain enhancements up to 104 at the band-edges, while considering disorder, absorption and coupling.
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Enhanced Stimulated Raman Scattering in slow-light photonic crystal waveguides
Optics letters, 2006Co-Authors: James F. Mcmillan, Nicolae C. Panoiu, Richard M. Osgood, Xiaodong Yang, Chee Wei WongAbstract:We investigate for the first time the enhancement of the Stimulated Raman Scattering in slow-light Silicon-on-Insulator (SOI) photonic crystal line defect waveguides. By applying the Bloch-Floquet formalism to the guided modes in a planar photonic crystal, we develop a formalism that relates the intensity of the down-shifted Stokes signal to the pump intensity and the modal group velocities. The formalism is then applied to two prospective schemes for enhanced Stimulated Raman generation in slow-light photonic crystal waveguides. The results demonstrate a maximum factor of 10^4 (66,000) enhancement with respect to SOI channel waveguides. Effects of two photon absorption, intrinsic Scattering, and disorder with respect to slow-light Raman generation towards optically-pumped silicon amplifiers and lasers are also discussed.
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enhanced Stimulated Raman Scattering in slow light photonic crystal waveguides
Optics Letters, 2006Co-Authors: James F. Mcmillan, Nicolae C. Panoiu, Richard M. Osgood, Xiaodong Yang, Chee Wei WongAbstract:We investigate for the first time, to our knowledge, the enhancement of the Stimulated Raman Scattering in slow-light silicon-on-insulator (SOI) photonic crystal line defect waveguides. By applying the Bloch-Floquet formalism to the guided modes in a planar photonic crystal, we develop a formalism that relates the intensity of the downshifted Stokes signal to the pump intensity and the modal group velocities. The formalism is then applied to two prospective schemes for enhanced Stimulated Raman generation in slow-light photonic crystal waveguides. The results demonstrate a maximum factor of 104(66,000) enhancement with respect to SOI channel waveguides.
Christian W Freudiger - One of the best experts on this subject based on the ideXlab platform.
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Stimulated Raman Scattering microscopy with a robust fibre laser source
Nature Photonics, 2014Co-Authors: Christian W Freudiger, Wenlong Yang, Gary R Holtom, Nasser N Peyghambarian, Khanh KieuAbstract:A dual-wavelength fibre laser source has been developed for Stimulated Raman Scattering microscopy. It is precisely tunable over the entire high-wavenumber region of Raman spectra, where most Stimulated Raman Scattering imaging is performed. Imaging speeds of up to 1 frame s−1 with shot-noise-limited sensitivity were achieved.
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Stimulated Raman Scattering microscopy with a robust fibre laser source
Nature Photonics, 2014Co-Authors: Christian W Freudiger, Wenlong Yang, Gary R Holtom, Sunney X Xie, N Peyghambarian, Khanh KieuAbstract:Stimulated Raman Scattering microscopy allows label-free chemical imaging and has enabled exciting applications in biology, material science, and medicine. It provides a major advantage in imaging speed over spontaneous Raman Scattering and has improved image contrast and spectral fidelity compared to coherent anti-Stokes Raman. Wider adoption of the technique has, however, been hindered by the need for a costly and environmentally sensitive tunable ultra-fast dual-wavelength source. We present the development of an optimized all-fibre laser system based on the optical synchronization of two picosecond power amplifiers. To circumvent the high-frequency laser noise intrinsic to amplified fibre lasers, we have further developed a high-speed noise cancellation system based on voltage-subtraction autobalanced detection. We demonstrate uncompromised imaging performance of our fibre-laser based Stimulated Raman Scattering microscope with shot-noise limited sensitivity and an imaging speed up to 1 frame/s.
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hyperspectral imaging with Stimulated Raman Scattering by chirped femtosecond lasers
Journal of Physical Chemistry B, 2013Co-Authors: Dan Fu, Christian W Freudiger, Gary R Holtom, Xu ZhangAbstract:Raman microscopy is a quantitative, label-free, and noninvasive optical imaging technique for studying inhomogeneous systems. However, the feebleness of Raman Scattering significantly limits the use of Raman microscopy to low time resolutions and primarily static samples. Recent developments in narrowband Stimulated Raman Scattering (SRS) microscopy have significantly increased the acquisition speed of Raman based label-free imaging by a few orders of magnitude, at the expense of reduced spectroscopic information. On the basis of a spectral focusing approach, we present a fast SRS hyperspectral imaging system using chirped femtosecond lasers to achieve rapid Raman spectra acquisition while retaining the full speed and image quality of narrowband SRS imaging. We demonstrate that quantitative concentration determination of cholesterol in the presence of interfering chemical species can be achieved with sensitivity down to 4 mM. For imaging purposes, hyperspectral imaging data in the C–H stretching region is...
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multicolor Stimulated Raman Scattering microscopy with a rapidly tunable optical parametric oscillator
Optics Letters, 2013Co-Authors: Lingjie Kong, Minbiao Ji, Dan Fu, Gary R Holtom, Christian W FreudigerAbstract:Stimulated Raman Scattering (SRS) microscopy allows label-free chemical imaging based on vibrational spectroscopy. Narrowband excitation with picosecond lasers creates the highest signal levels and enables imaging speeds up to video-rate, but it sacrifices chemical specificity in samples with overlapping bands compared to broadband (multiplex) excitation. We develop a rapidly tunable picosecond optical parametric oscillator with an electro-optical tunable Lyot filter, and demonstrate multicolor SRS microscopy with synchronized line-by-line wavelength tuning to avoid spectral artifacts due to sample movement. We show sensitive imaging of three different kinds of polymer beads and live HeLa cells with moving intracellular lipid droplets.
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multicolor Stimulated Raman Scattering microscopy
Molecular Physics, 2012Co-Authors: Fake Lu, Minbiao Ji, Christian W Freudiger, Dan Fu, Xiaohui Ni, Gary R HoltomAbstract:Stimulated Raman Scattering (SRS) microscopy has opened up a wide range of biochemical imaging applications by probing a particular Raman-active molecule vibrational mode in the specimen. However, the original implementation with picosecond pulse excitation can only realize rapid chemical mapping with a single Raman band. Here we present a novel SRS microscopic technique using a grating-based pulse shaper for excitation and a grating-based spectrograph for detection to achieve simultaneous multicolor SRS imaging with high sensitivity and high acquisition speeds. In particular, we use a linear combination of the measured CH2 and CH3 stretching signals to map the distributions of protein and lipid contents simultaneously.
Gary R Holtom - One of the best experts on this subject based on the ideXlab platform.
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Stimulated Raman Scattering microscopy with a robust fibre laser source
Nature Photonics, 2014Co-Authors: Christian W Freudiger, Wenlong Yang, Gary R Holtom, Sunney X Xie, N Peyghambarian, Khanh KieuAbstract:Stimulated Raman Scattering microscopy allows label-free chemical imaging and has enabled exciting applications in biology, material science, and medicine. It provides a major advantage in imaging speed over spontaneous Raman Scattering and has improved image contrast and spectral fidelity compared to coherent anti-Stokes Raman. Wider adoption of the technique has, however, been hindered by the need for a costly and environmentally sensitive tunable ultra-fast dual-wavelength source. We present the development of an optimized all-fibre laser system based on the optical synchronization of two picosecond power amplifiers. To circumvent the high-frequency laser noise intrinsic to amplified fibre lasers, we have further developed a high-speed noise cancellation system based on voltage-subtraction autobalanced detection. We demonstrate uncompromised imaging performance of our fibre-laser based Stimulated Raman Scattering microscope with shot-noise limited sensitivity and an imaging speed up to 1 frame/s.
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Stimulated Raman Scattering microscopy with a robust fibre laser source
Nature Photonics, 2014Co-Authors: Christian W Freudiger, Wenlong Yang, Gary R Holtom, Nasser N Peyghambarian, Khanh KieuAbstract:A dual-wavelength fibre laser source has been developed for Stimulated Raman Scattering microscopy. It is precisely tunable over the entire high-wavenumber region of Raman spectra, where most Stimulated Raman Scattering imaging is performed. Imaging speeds of up to 1 frame s−1 with shot-noise-limited sensitivity were achieved.
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hyperspectral imaging with Stimulated Raman Scattering by chirped femtosecond lasers
Journal of Physical Chemistry B, 2013Co-Authors: Dan Fu, Christian W Freudiger, Gary R Holtom, Xu ZhangAbstract:Raman microscopy is a quantitative, label-free, and noninvasive optical imaging technique for studying inhomogeneous systems. However, the feebleness of Raman Scattering significantly limits the use of Raman microscopy to low time resolutions and primarily static samples. Recent developments in narrowband Stimulated Raman Scattering (SRS) microscopy have significantly increased the acquisition speed of Raman based label-free imaging by a few orders of magnitude, at the expense of reduced spectroscopic information. On the basis of a spectral focusing approach, we present a fast SRS hyperspectral imaging system using chirped femtosecond lasers to achieve rapid Raman spectra acquisition while retaining the full speed and image quality of narrowband SRS imaging. We demonstrate that quantitative concentration determination of cholesterol in the presence of interfering chemical species can be achieved with sensitivity down to 4 mM. For imaging purposes, hyperspectral imaging data in the C–H stretching region is...
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multicolor Stimulated Raman Scattering microscopy with a rapidly tunable optical parametric oscillator
Optics Letters, 2013Co-Authors: Lingjie Kong, Minbiao Ji, Dan Fu, Gary R Holtom, Christian W FreudigerAbstract:Stimulated Raman Scattering (SRS) microscopy allows label-free chemical imaging based on vibrational spectroscopy. Narrowband excitation with picosecond lasers creates the highest signal levels and enables imaging speeds up to video-rate, but it sacrifices chemical specificity in samples with overlapping bands compared to broadband (multiplex) excitation. We develop a rapidly tunable picosecond optical parametric oscillator with an electro-optical tunable Lyot filter, and demonstrate multicolor SRS microscopy with synchronized line-by-line wavelength tuning to avoid spectral artifacts due to sample movement. We show sensitive imaging of three different kinds of polymer beads and live HeLa cells with moving intracellular lipid droplets.
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multicolor Stimulated Raman Scattering microscopy
Molecular Physics, 2012Co-Authors: Fake Lu, Minbiao Ji, Christian W Freudiger, Dan Fu, Xiaohui Ni, Gary R HoltomAbstract:Stimulated Raman Scattering (SRS) microscopy has opened up a wide range of biochemical imaging applications by probing a particular Raman-active molecule vibrational mode in the specimen. However, the original implementation with picosecond pulse excitation can only realize rapid chemical mapping with a single Raman band. Here we present a novel SRS microscopic technique using a grating-based pulse shaper for excitation and a grating-based spectrograph for detection to achieve simultaneous multicolor SRS imaging with high sensitivity and high acquisition speeds. In particular, we use a linear combination of the measured CH2 and CH3 stretching signals to map the distributions of protein and lipid contents simultaneously.
