Magnetic Resonance Imaging (MRI)

Scanners     Probes     Specific Capabilities

Scanners

The MagLab has state-of-the art facilities to conduct MRI, diffusion and in vivo studies at record-high magnetic fields.

In Tallahassee, we have vertical widebore magnets that are capable of performing MR microimaging for both in vivo, in vitro and materials applications. They are equipped with Bruker Avance spectrometers and widebore imaging gradients providing diameters up to 63 mm on the 21.1 T magnet.

In Gainesville, we have a 750 MHz (17.6 tesla) widebore (89-mm) system for microimaging and in vivo imaging and spectroscopy with a 600 MHz (14 tesla) standard bore (52-mm) system for microimaging. Both systems are Bruker Avance consoles. There are two horizontal scanners (4.7 T/33 cm and 11.1 T/40 cm) dedicated for animal imaging, and a 3 tesla human scanner for translational studies.

External users can utilize animal facilities and technicians at both locations.

In Tallahassee 900 MHz 600 MHz

In Gainesville 750 MHz 600 MHz 470 MHz (11.1 T) 200 MHz (4.7 T) 3 T human scanner

Probes

MR Imaging at 21.T

The ultra-widebore 900-MHz magnet presents a unique opportunity for high-field in vivo magnetic resonance microscopy. The recently developed in vivo MRI RF probe (ID 33 mm) makes possible MRI of animals using proton, sodium, carbon and chlorine nuclei. The probe can accommodate neural studies on rats up to 350 g, whole body studies of mice and ex vivo/in vitro studies of materials and tissues.

In collaboration with the MRI program at the MagLab’s AMRIS facility at the University of Florida, we are translating a variety of RF coils and animal support systems to other widebore vertical systems to accommodate in vivo animal and large specimen microimaging on numerous imaging platforms.

21 T in vivo rodent probe with the following coils:

• 33 mm ¹H linear birdcage
• 33 mm ²³Na linear birdcage
• 33 mm ¹H/²³Na linear birdcage
• 33 mm ¹H/¹³C linear birdcage
• 33 mm ³⁵Cl quadrature birdcage
• 20 mm ¹H quadrature half-saddle coil

Ex vivo and in vivo coils:

• Bruker micro2.5 linear birdcages (30, 10 and 5 mm)
• Homebuilt single- and double-tuned RF microcoils (<500 μm diameters)
• 4 mm ¹H linear dielectric resonator

900 MHz probe development for imaging of rodents

Phased Array Hardware

In Tallahassee, the 900 MHz ultra-widebore magent is equipped with four receive channels for parallel imaging. At AMRIS, the 4.7 and 11.1 tesla magnets also are equipped with four channels for transmit and receive phased array operation. A large number of in-house, custom-built array coils are available. The Phillips 3 T/90 cm magnet is fully operational and is available for human MRI on research subjects and for larger animal studies using current receive-only array technology.

Imaging RF Technology

RF groups in Tallahassee and Gainesville have worked both in collaboration and independently to develop a number of novel RF designs to optimize imaging applications on vertical and horizontal systems. The ReCav design was pioneered at AMRIS to develop homogeneous RF detection and reception for large samples in horizontal magnets. Microcoil designs have been implemented for small specimen analysis at both sites on vertical magnets. Unique double-tuned RF coils that investigate multiple nuclei simultaneously or sequentially have been designed at the MagLab and are being implemented at both sites.

Specific Capabilities

Microimaging Experiments

Several vertical magnets in the MR program are equipped with either commercial or prototype microimaging gradients and amplifiers that can accommodate sample sizes between 100 microns and hundreds of millimeters. Various commercial and in-house coils are available for these investigations.

Hyperpolarized ¹²⁹Xe and ³He

New spin exchange optical pumping system for the generation of hyperpolarized ¹²⁹Xe and ³He is now available. The polarized noble gas generator incorporates the highest power fiber coupled diode array laser system ever used for spin exchange optical pumping. The system has been designed to be self-contained for maximum functionality and portability to support a wide variety of hyperpolarized ¹²⁹Xe and ³He NMR and MRI experiments at AMRIS. NMR applications already underway include studies of surfaces, binding sites in proteins, phase transitions, and gas clathrate hydrates.

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For questions regarding your experimental needs please contact Victor Schepkin for Tallahassee-based facilities or Joanna Long for the Gainesville-based AMRIS facility.