Multiphoton Confocal Microscope System A1R MP+

Resonant Scanner Enables Imaging Up To 420fps

Nikon’s exclusive resonant scanner is capable of imaging a wide area at a much higher speed than a non-resonant scanner, making it possible for 420-fps imaging using point scanning technology. The NDD for multiphoton microscopy makes it possible to image fast and deep through the thickest specimens. Nikon’s optical pixel clock system allows more stable and more evenly illuminated imaging— even at high speeds.

Visualization of intravital microcirculation
Blood cells in blood vessels within a living organism were excited by a femtosecond pulsed IR laser with the A1R MP⁺‘ ultrahigh-speed resonant scanner, and their movements were simultaneously captured in three successive fluorescence images at 30 fps (30 msec), with three separate color channels.
Three fluorescent probes are simultaneously excited and imaged–nucleus (blue), endothelium (green), and plasma (red). The long-wavelength ultrafast laser in combination with the ultrahigh-speed resonant scanner effectively reduces photodamage and makes time resolved multiphoton imaging of biomolecules possible.

Image resolution: 512 x 512 pixels, Image acquisition speed: 30 fps, Objective: water immersion objective 60x

Imaged with the cooperation of: Dr. Satoshi Nishimura, Department of Cardiovascular Medicine, the University of Tokyo, TSBMI, the University of Tokyo, PRESTO, Japan Science and Technology Agency

Revolutionary Hybrid Confocal Scan Head

The A1R+ has a hybrid scanner head that incorporates both an ultrahigh-speed resonant scanner and a high-resolution galvano scanner. Simultaneous photoactivation and ultrafast imaging using these two scanners allow acquisition of rapid changes after photoactivation and enables observation of intermolecular interaction.

HeLa cells expressing Yellow Cameleon 3.60 were excited with 457 nm laser light. After stimulation with histamine, calcium ion concentration dynamics were observed. The (blue) emission of CFP and the (yellow) emission of YFP are shown as green and red channels respectively. The graph displays fluorescence intensity (vertical) versus time (horizontal). The green and red lines in the graph indicate the intensity change of CFP emission (green) and YFP emission (red) from the region of interest (ROI). Along with the increase of calcium ion concentration in the cell, the intermolecular FRET efficiency between CFP and YFP within Yellow Cameleon 3.60 increases, the CFP fluorescence intensity decreases, and the YFP fluorescence intensity increases. Imaging laser wavelength: 457 nm, Image size: 512 x 512 pixels, 30 fps (with resonant scanner) Photos courtesy of: Dr. Kenta Saito and Prof. Takeharu Nagai, Research Institute for Electronic Science, Hokkaido University

in vivo High-Speed imaging

The Nikon resonant scanner is capable of high-speed 420-fps imaging. Unique to this design is a resonant scan mirror capable of imaging full fields of view at much higher speeds than traditional galvano scanners. Nikon’s optical pixel clock system, which monitors the position of the resonant mirror in real time, adjusts the pixel clock to ensure more stable, geometrically correct and more evenly illuminated imaging even at high speeds. This enables the successful visualization of in vivo rapid changes, such as reactions in living organisms, dynamics and cell interactions.

Deep Specimen Imaging with High-sensitivity Non-Descanned Detectors (NDD)

The fluorescence emissions from deep within a specimen are highly scattered in multiphoton excitation, and therefore the conventional detector using a pinhole cannot provide bright fluorescent images. The episcopic NDD in the A1R MP+ is located close to the back aperture of the objective to detect the maximum amount of scattered emission signals from deep within living specimens.

In vivo image of deep areas of cerebral cortex of a mouse

The cerebral cortex of an H-line 5-week-old mouse was studied with the open skull method. The entire shape of dendrites of pyramidal cells in layer V expressing EYFP were visualized from the bottom layer into a superficial layer. In addition, the fluorescence signal of white matter in deeper areas was also studied.

Mouse cerebral cortex multi-color imaging

Simultaneous acquisition of three channels in anesthetized YFP-H mouse using IR excitation of 950 nm and imaging Second Harmonic Generation (SHG) and two fluorescence emissions.
Cyan: SHG signal of dura mater
Yellow: EYFP pyramidal neurons in layer V of the cortex
Red: SRB-labeled blood vessels

Photographed with the cooperation of:
Drs. Ryosuke Kawakami, Terumasa Hibi and Tomomi Nemoto, Research Institute for Electronic Science, Hokkaido University

3D volume rendering images
Three-dimensional volume renderings of a kidney labeled with Hoxb7/myrVenus marker (Chi et al, 2009 Genesis), using depth-code pseudocolor volume rendering to reference Z depths (pseudocolored by depth – 1 μm step for 550 μm).

Objective: CFI Apochromat 25xW MP, Scan zoom: 1x, Z step size: 1 μm, IR excitation wavelength: 930 nm 
Image resolution: 1024×1024 pixels, Image volume: 460 μm (length) x 460 μm (width) x 600 μm (height)
Photographed with the cooperation of Dr. Frank Costantini and Dr. Liza Pon, Columbia University Medical Center, New York

1300nm Imaging

In addition to the GaAsP NDD compatible with a wavelength of 1080nm, there is a new model for upright microscopes that is compatible with a wavelength of 1300 nm. This new NDD enables deep imaging up to 1.4 mm in combination with a newly developed scanning head A1R MP+ that is compatible with a wavelength of 1300 nm.

Deep brain imaging in in vivo mouse with the GaAsP NDD compatible with the 1300 nm wavelength

Photographed with the cooperation of: Drs. Ryosuke Kawakami, Terumasa Hibi and Tomomi Nemoto, Research Institute for Electronic Science, Hokkaido University

In vivo imaging of an anesthetized YFP-H mouse (4-week-old) via open skull method. Visualization of the entire layer V pyramidal neurons and the deeper hippocampal neurons. Deep imaging achieved for 3-dimensional imaging of hippocampal dendrites up to 1.4 mm into the brain.

Captured with episcopic GaAsP NDD for 1300 nm and CFI75 Apochromat 25xW MP1300 objective lens (NA 1.10, WD 2.0 mm)
Excitation wavelength: 1040 nm

Mouse brain in vivo dual color imaging with the GaAsP NDD compatible with the 1300 nm wavelength

The cerebral cortex of an anesthetized YFP-H mouse (4-week-old) was studied with the open skull method.
Alexa594 was injected into the tail vein to visualize the blood vessel.

Photographed with the cooperation of: Drs. Ryosuke Kawakami, Terumasa Hibi and Tomomi Nemoto, Research Institute for Electronic Science, Hokkaido University

NEW Dual IR Beam Option Enables Simultaneous Two-Color Multiphoton Imaging

With the dual IR beam option, users can now simultaneously excite two different fluorophores such as GFP and mCherry.  This capability enables ultra-fast two-color multiphoton imaging, ideal for dynamic specimens.  The dual beams can also be used for stimulation at a specific wavelength and imaging with a different wavelength, reducing time delays normally present when using a single beam which requires mode locking to change wavelengths.

Live brain slice expressing YFP and Rhod-2, simultaneously excited with 900nm and 1040nm wavelengths (CFI75 LWD Apo 25x 1.1 NA W 1300nm objective).  A live slice culture from a YFP-VGAT rat stained with rhod-2 AM was imaged to measure mitochondrial calcium transients in hippocampal interneurons.

Image courtesy of Richard Kovacs, Ph.D., Institute for Neurophysiology, Charité-Medical University, Berlin, Germany

 Nikon High-NA Objectives are Ideal for Multiphoton Imaging

High-NA objectives have been developed that highly correct chromatic aberrations over a wide wavelength range, from ultraviolet to infrared. Transmission is increased through the use of Nikon’s exclusive Nano Crystal Coat technology.

In particular, the CFI75 Apochromat 25xW MP/MP1300 objective lenses provide an industry leading highest numerical aperture of 1.10 while still maintaining a 2.0 mm working distance. They also have a collar that corrects spherical aberrations depending on the depth of the specimen and a 33° manipulator pipette access angle, making it ideal for deep multiphoton imaging and physiology research applications.
Nano Crystal Coat is a Nikon exclusive lens coating technology using an ultralow refractive index nanoparticle thin film originally developed for the semiconductor fabrications industry. The Nano Crystal Coat particle structure dramatically reduces stray reflections and boosts transmission over a wide wavelength range, producing images with higher signal-to-noise (S/N) ratios.

CFI75 Apochromat 25xW MP CFI Apochromat LWD 40xWI λS

CFI Apochromat 40xWI λS CFI Plan Apochromat IR 60xWI

CFI Apochromat LWD 20xWI λS

Objectives for multiphoton microscopy

Auto Laser Alignment when Changing Multiphoton Excitation Wavelength

When the multiphoton laser wavelength or group velocity dispersion pre-compensation is changed, the multiphoton laser beam positional pointing at the objective back aperture may also change, resulting in uneven intensity across the image, or a slight misalignment between the IR and visible laser light paths.

Verifying the IR laser beam pointing and setting the alignment has traditionally been difficult. The A1R MP+ auto laser alignment function, housed in the Incident Optical Unit for the multiphoton excitation light path, automatically maximizes IR laser alignments with a single click in NIS-Elements C.

Two Types of Scanning Heads Enable High-speed, High-quality Imaging

A1R MP+ has a hybrid scanning head that incorporates both a high-resolution galvano scanner and an ultrahigh-speed resonant scanner. The galvano scanner enables imaging up to 4096 x 4096 pixels and high-speed acquisition of 10 fps (512 x 512 pixels). A new A1R MP+ system is now available which is compatible with a wavelength of 1300 nm.