Unique System Features
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Combines multiple imaging modalities in a single instrument with dynamic mode switching (see below)
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Achieves previously established benchmarks of all imaging modes (e.g. spatial resolution, light sheet thickness) in a single instrument
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Extended light sheet imaging tile size (220 um)
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Contains light sheet, inverted, and upright imaging objectives
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Uses a 25 mm coverslip
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Coverslip "quick scan" for optimal sample finding
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Temperature-controlled sample chamber with CO2 gas control
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Seven illumination wavelengths
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Simultaneous two-color or sequential multi-color light sheet microscopy
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Adaptive-optics correction (wavefront sensing) for both excitation and emission light paths for all imaging modes
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Two sCMOS cameras for multiple color (simultaneous) imaging, FRET, and spectra separation
Currently Available Imaging Modes
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Lattice light sheet with Adaptive Optics
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Expansion microscopy (ExM) imaging with lattice light sheet
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Localized photoactivation, photoconversion, and photoablation
Imaging Modes In-Development (Not Currently Offered)
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3D structured illumination super resolution
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Multifocal image scan/pixel reassignment super resolution
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Two photon (2P) point scan
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2P Bessel fast functional imaging (upright objective)
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2P Bessel light sheet
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2P Bessel point scan
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Phase imaging
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Patterned photostimulation
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3D single-molecule localization
System Specifications
Available Lasers (in nm):
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405 (Oxxius diode laser, rated 100 mW)
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445 (Oxxius diode laser, rated 100 mW)
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488 (MPB fiber laser, rated 500 mW)
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514 (MPB fiber laser, rated 1 W)
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560 (MPB fiber laser, rated 1 W)
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607 (MPB fiber laser, rated 1 W)
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642 (MPB fiber laser, rated 2 W)
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Chameleon LSII 2P laser (680 nm - 1080 nm, 3.5 W peak power)
Objectives:
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Light Sheet Excitation: Special Optics 0.65 NA, 3.74 mm working water dipping lens
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Light Sheet Detection/Inverted/Upright: Zeiss 1.0 NA water-dipping objectives with 2.2 mm working distance
Cameras
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2x Hamamatsu Orca Flash 4.0 v3 sCMOS
Limitations
Although a novel and powerful tool for biomedical imaging, the scope does have limitations.
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It can take several seconds to change imaging modes; this has to be accounted for when planning complex, high temporally resolved experiments.
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Simultaneous multi-color imaging mode is limited to two colors.
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Spatial resolution is slightly lower than traditional LLSM, and therefore more conventional "cell on a coverslip" volumetric imaging is better suited for the LLSM (more info here).
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Large-volume acquisitions with adaptive optics may require tiling for optimal aberration corrections, which reduces temporal resolution.
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Adaptive optics is most effective in weakly-scattering samples, such as Zebrafish. Adaptive optics will not remedy the effects of light scattering.
Instrument Summary
At the leading edge of microscopy is the quest to capture biology as it occurs in its natural environment. It is clear that for decades studies have yielded excellent information from interrogating cells on a coverslip, but truly understanding biological systems requires observation in more natural conditions. The advent of modern fluorescent light sheet microscopy has made it possible to capture live biology with much less perturbation due to laser light intensity. This also improved diffraction-limited image quality by only illuminating within the focal depth of the detection objective, thereby improving signal-to-background [1,2]. However these instruments still have limitations. Light experiences significant distortions when going through thick (>100 um) tissues; this causes unacceptable image degradation.
Recently, the Betzig lab at HHMI Janelia coupled the principles of adaptive optics with lattice light sheet microscopy [3]. By using a 2P laser spot (a "guide star") that is focused in the imaging volume, wavefront sensing allows for quantification of the aberration the light experiences. This aberration can then be corrected by a deformable mirror (emission correction) or adjusting the shape of the incoming light with a spatial light modulator (excitation correction). This creates an instrument that is capable of gentle illumination, high contrast imaging, and improved imaging penetration depth. With the new Multimodal Optical Scope with Adaptive Imaging Correction (MOSAIC), the users can currently take advantage of multi-modal imaging to, for example, interlace localized photoactivation with long-term volumetric, gentle imaging with LLSM, using adaptive optics correction in both modes. Additionally, with simultaneous two-color imaging in all modes and large tile sizes, volumes can be captured several times faster than conventional, sequentially scanned imaging modalities. Users interested in leveraging the multi-modal nature of this instrument must discuss their project with the AIC team prior to submitting a proposal.
Suggested Reading
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Planchon, T. A., et al. Rapid three-dimensional isotropic imaging of living cells using Bessel beam plane illumination. Nat. Methods 8, 417–23 (2011).
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Chen, B.C., et al. Lattice light-sheet microscopy: imaging molecules to embryos at high spatiotemporal resolution. Science 346, (2014).
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Liu, T.-L., et al. Observing the cell in its native state: Imaging subcellular dynamics in multicellular organisms. Science 20, (2018).