Imaging live cells at high spatiotemporal resolution for lab-on-a-chip applications

The synergy of novel super-resolution imaging techniques and microfluidic technology provides new biological and biomedical insights into sub-cellular processes.

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3D super-resolved imaging in live cells using sub-diffractive plasmonic localization of hybrid nanopillar arrays

Nanophotonics ◽

10.1515/nanoph-2020-0105 ◽

2020 ◽

Vol 9 (9) ◽

pp. 2847-2859

Author(s):

Soojung Kim ◽

Hyerin Song ◽

Heesang Ahn ◽

Seung Won Jun ◽

Seungchul Kim ◽

...

Keyword(s):

Signal To Noise Ratio ◽

Imaging Techniques ◽

Optical Loss ◽

Super Resolution ◽

Living Cells ◽

Live Cells ◽

Complex Biological System ◽

Observation Volume ◽

Resolution Imaging ◽

Nanopillar Arrays

AbstractAnalysing dynamics of a single biomolecule using high-resolution imaging techniques has been had significant attentions to understand complex biological system. Among the many approaches, vertical nanopillar arrays in contact with the inside of cells have been reported as a one of useful imaging applications since an observation volume can be confined down to few-tens nanometre theoretically. However, the nanopillars experimentally are not able to obtain super-resolution imaging because their evanescent waves generate a high optical loss and a low signal-to-noise ratio. Also, conventional nanopillars have a limitation to yield 3D information because they do not concern field localization in z-axis. Here, we developed novel hybrid nanopillar arrays (HNPs) that consist of SiO2 nanopillars terminated with gold nanodisks, allowing extreme light localization. The electromagnetic field profiles of HNPs are obtained through simulations and imaging resolution of cell membrane and biomolecules in living cells are tested using one-photon and 3D multiphoton fluorescence microscopy, respectively. Consequently, HNPs present approximately 25 times enhanced intensity compared to controls and obtained an axial and lateral resolution of 110 and 210 nm of the intensities of fluorophores conjugated with biomolecules transported in living cells. These structures can be a great platform to analyse complex intracellular environment.

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Super-Resolution Imaging in Fluid Mechanics Using New Illumination Approaches

Annual Review of Fluid Mechanics ◽

10.1146/annurev-fluid-010719-060059 ◽

2020 ◽

Vol 52 (1) ◽

pp. 369-393

Author(s):

Minami Yoda

Keyword(s):

Fluid Mechanics ◽

Total Internal Reflection ◽

Imaging Techniques ◽

Super Resolution ◽

Internal Reflection ◽

Interfacial Flows ◽

Structured Illumination ◽

Structured Illumination Microscopy ◽

Entire Volume ◽

Resolution Imaging

Quantifying submillimeter flows using optical diagnostic techniques is often limited by a lack of spatial resolution and optical access. This review discusses two super-resolution imaging techniques, structured illumination microscopy and total internal reflection fluorescence or microscopy, which can visualize bulk and interfacial flows, respectively, at spatial resolutions below the classic diffraction limits. First, we discuss the theory and applications of structured illumination for optical sectioning, i.e., imaging a thin slice of a flow illuminated over its entire volume. Structured illumination can be used to visualize the interior of multiphase flows such as sprays by greatly reducing secondary scattering. Second, the theory underlying evanescent waves is introduced, followed by a review of how total internal reflection microscopy has been used to visualize interfacial flows over the last 15 years. Both techniques, which are starting to be used in fluid mechanics, could significantly improve quantitative imaging of microscale and macroscale flows.

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Fluorescence imaging with tailored light

Nanophotonics ◽

10.1515/nanoph-2019-0227 ◽

2019 ◽

Vol 8 (12) ◽

pp. 2111-2128 ◽

Cited By ~ 3

Author(s):

Jialei Tang ◽

Jinhan Ren ◽

Kyu Young Han

Keyword(s):

Fluorescence Imaging ◽

Imaging Techniques ◽

Super Resolution ◽

Optical Parameters ◽

Propagation Angle ◽

Resolution Imaging ◽

Time Observation ◽

Living Organisms ◽

Real Time Observation

AbstractFluorescence microscopy has long been a valuable tool for biological and medical imaging. Control of optical parameters such as the amplitude, phase, polarization, and propagation angle of light gives fluorescence imaging great capabilities ranging from super-resolution imaging to long-term real-time observation of living organisms. In this review, we discuss current fluorescence imaging techniques in terms of the use of tailored or structured light for the sample illumination and fluorescence detection, providing a clear overview of their working principles and capabilities.

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Super-Resolution Imaging by Dual Iterative Structured Illumination Microscopy

10.1101/2021.05.12.443720 ◽

2021 ◽

Author(s):

Anna Loeschberger ◽

Yauheni Novikau ◽

Ralf Netz ◽

Marie-Christin Spindler ◽

Ricardo Benavente ◽

...

Keyword(s):

Three Dimensional ◽

Brain Slices ◽

Super Resolution ◽

Reconstruction Algorithm ◽

Living Cells ◽

Structured Illumination ◽

Structured Illumination Microscopy ◽

Spatiotemporal Resolution ◽

Coated Pits ◽

Resolution Imaging

Three-dimensional (3D) multicolor super-resolution imaging in the 50-100 nm range in fixed and living cells remains challenging. We extend the resolution of structured illumination microscopy (SIM) by an improved nonlinear iterative reconstruction algorithm that enables 3D multicolor imaging with improved spatiotemporal resolution at low illumination intensities. We demonstrate the performance of dual iterative SIM (diSIM) imaging cellular structures in fixed cells including synaptonemal complexes, clathrin coated pits and the actin cytoskeleton with lateral resolutions of 60-100 nm with standard fluorophores. Furthermore, we visualize dendritic spines in 70 micrometer thick brain slices with an axial resolution < 200 nm. Finally, we image dynamics of the endoplasmatic reticulum and microtubules in living cells with up to 255 frames/s.

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Super-resolution imaging of bacterial pathogens and visualization of their secreted effectors

FEMS Microbiology Reviews ◽

10.1093/femsre/fuaa050 ◽

2020 ◽

Author(s):

Moirangthem Kiran Singh ◽

Linda J Kenney

Keyword(s):

Virulence Factors ◽

Protein Secretion ◽

Fluorescent Probes ◽

Imaging Techniques ◽

Super Resolution ◽

Bacterial Pathogenesis ◽

Secretion Systems ◽

Complex Protein ◽

Resolution Imaging ◽

Protein Secretion Systems

ABSTRACT Recent advances in super-resolution imaging techniques, together with new fluorescent probes have enhanced our understanding of bacterial pathogenesis and their interplay within the host. In this review, we provide an overview of what these techniques have taught us about the bacterial lifestyle, the nucleoid organization, its complex protein secretion systems, as well as the secreted virulence factors.

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High-dimensional super-resolution imaging reveals heterogeneity and dynamics of subcellular lipid membranes

Nature Communications ◽

10.1038/s41467-020-19747-0 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Karl Zhanghao ◽

Wenhui Liu ◽

Meiqi Li ◽

Zihan Wu ◽

Xiao Wang ◽

...

Keyword(s):

Lipid Membranes ◽

Developmental Stages ◽

Membrane Separation ◽

Optical Tomography ◽

Super Resolution ◽

Live Cells ◽

Lipid Dynamics ◽

Membrane Morphology ◽

Intracellular Organelles ◽

Resolution Imaging

AbstractLipid membranes are found in most intracellular organelles, and their heterogeneities play an essential role in regulating the organelles’ biochemical functionalities. Here we report a Spectrum and Polarization Optical Tomography (SPOT) technique to study the subcellular lipidomics in live cells. Simply using one dye that universally stains the lipid membranes, SPOT can simultaneously resolve the membrane morphology, polarity, and phase from the three optical-dimensions of intensity, spectrum, and polarization, respectively. These high-throughput optical properties reveal lipid heterogeneities of ten subcellular compartments, at different developmental stages, and even within the same organelle. Furthermore, we obtain real-time monitoring of the multi-organelle interactive activities of cell division and successfully reveal their sophisticated lipid dynamics during the plasma membrane separation, tunneling nanotubules formation, and mitochondrial cristae dissociation. This work suggests research frontiers in correlating single-cell super-resolution lipidomics with multiplexed imaging of organelle interactome.

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Cyclo‐Ketal Xanthene Dyes: A New Class of Near‐Infrared Fluorophores for Super‐Resolution Imaging of Live Cells

Chemistry - A European Journal ◽

10.1002/chem.202005296 ◽

2020 ◽

Author(s):

Xinfu Zhang ◽

Lingcheng Chen ◽

Zhenlong Huang ◽

Ni Ling ◽

Yi Xiao

Keyword(s):

Near Infrared ◽

Super Resolution ◽

Live Cells ◽

Xanthene Dyes ◽

New Class ◽

Resolution Imaging

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Super-Resolution Microscopy of Chromatin

Genes ◽

10.3390/genes10070493 ◽

2019 ◽

Vol 10 (7) ◽

pp. 493 ◽

Cited By ~ 1

Author(s):

Birk

Keyword(s):

Gene Regulation ◽

Data Analysis ◽

Super Resolution ◽

Fluorescence Labeling ◽

Cellular Processes ◽

Direct Assessment ◽

Chromatin Interactions ◽

Resolution Imaging ◽

Super Resolution Microscopy ◽

Insight Into

Since the advent of super-resolution microscopy, countless approaches and studies have been published contributing significantly to our understanding of cellular processes. With the aid of chromatin-specific fluorescence labeling techniques, we are gaining increasing insight into gene regulation and chromatin organization. Combined with super-resolution imaging and data analysis, these labeling techniques enable direct assessment not only of chromatin interactions but also of the function of specific chromatin conformational states.

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