A new pH sensitive contrast agent for MR imaging has been developed that produces image contrast based on the local pH and that has great potential for use in living animals and medical diagnostics.
Have you ever wondered how your diet affects your heart? Or your liver? And not just for your general health, but at a molecular level? What is that cheeseburger doing to your heart, anyway?
Matt Merritt, an associate professor of biochemistry and molecular biology at the University of Florida (UF), wants to help answer those questions. He studies the role of metabolic pathways in heart failure and fatty liver disease. Specifically, he looks at ATP — the molecule used by all living things to store and transport energy. The results of his work have the potential to improve our understanding and treatment of illnesses as wide-ranging as heart disease, diabetes and cancer.
Using nuclear magnetic resonance (NMR) magnets and instrumentation available at the National MagLab's AMRIS Facility at UF, Merritt studies how carbon is involved in ATP generation. However, phosphorus, another important element in the final step of ATP generation, has been beyond his reach because the special tool required to study it wasn’t available. Studying phosphorous requires a certain kind of probe — a stick-like piece of equipment that holds the sample and allows the scientist to insert it into the magnet.
Now, thanks to the addition of a new cryoprobe at the AMRIS Facility, Merritt and other MagLab users will be able to monitor phosphorus dynamics. With its electronics operating at very low, cryogenic temperatures, this probe enables monitoring of phosphorous-containing compounds at physiologic concentrations and will allow Merritt's group to gain a fuller understanding of metabolism (instead of studying carbon movement in isolation).
The new probe is larger (with a 10-mm diameter sample space) than existing cryoprobes in the facility and, in addition to phosphorus, can detect carbon and sodium isotopes, enabling researchers to obtain higher sensitivity data on larger samples. This probe is connected to a commercially built dynamic nuclear polarization (DNP) system, another recent addition to the AMRIS Facility. The new DNP system, called HyperSense, is more automated than the facility's current DNP set-up, and can be operated by a single person, making it more user-friendly. The HyperSense, which is attached to the 600 MHz 51 mm NMR & MRI/S System and the new cryoprobe, will be available to users by the fall of 2018.
Photo: Researchers Ram Khattri (left) and Mukundan Ragavan work with the new cryoprobe. Photo by Elizabeth Webb.
Story by Elizabeth Webb.
Federal grant to fund new tools for biology research in high magnetic fields
This week at the lab, MagLab engineer Jason Kitchen is soldering into place capacitors smaller than a grain of rice to build a one-of-a-kind probe destined for a very large one-of-a-kind magnet.The magnet in question is the series connected hybrid magnet due to be commissioned this summer at the MagLab. The 36 tesla instrument will generate world-record magnetic fields that will be used primarily for nuclear magnetic resonance (NMR) experiments.
Kitchen is helping to build three probes that scientists will use to insert their specimens — including biological samples such as proteins and material samples such as lithium electrolytes to research better batteries — into the magnet.
Kitchen is currently at work on a cross polarization magic angle spinning probe that will spin biological samples inside the magnet at almost 40,000 times a second. He is building a set of tuning cards that can be quickly inserted and removed from the probe, allowing scientists to easily change from studying one combination of isotopes to another during experiments. This work involves painstakingly soldering teeny radio frequency components onto small PC boards and testing them to make sure they are in the exact spot that will produce the clearest signal for the scientist.
"When a chemist wants to change the probe to work at different frequencies, it's just a simple matter for us to slide in two tuning cards," said Kitchen.
Photo and text by Kristen Coyne.
Spinning faster than almost anything on Earth, this probe allows scientists to do NMR studies of solid state samples.
This probe allows biologists to study health problems such as migraines and head injuries using live animals as large as rats, making our 900 MHz magnet the largest MRI machine in the world.
This tool makes possible more research on heat-sensitive samples such as proteins.
Magnet probes are at once very simple and very complex. On the simple end, they are essentially sticks – about as tall as the scientists who use them – that allow researchers to place their experiment inside the magnet's field.
Without this instrument, the lab's high powered magnets would be useless.
A new 1.5-mm high-temperature superconducting probe designed to detect carbon 13 will significantly enhance studies in natural products and metabolomics.