A new method to study how the nuclei of atoms “communicate” with one another in the presence of unpaired electron spins has been developed at the MagLab. Known as hyperpolarization resurgence (HypRes), this method benefits and expands the application of a revolutionary technique known as dynamic nuclear polarization (DNP), which provides enormous signal enhancements in nuclear magnetic resonance (NMR) experiments.
This finding demonstrates a path forward to dramatically enhance sensitivity for molecule concentration measurement by magnetic resonance using Overhauser DNP.
Findings that “go against the textbooks” may improve biofuel production
With unprecedented sensitivity and resolution from state-of-the-art magnets, scientists have identified for the first time the cell wall structure of one of the most prevalent and deadly fungi.
In this study, researchers added a low concentration of the endohedral metallofullerene (EMF) Gd2@C79N to DNP samples, finding that 1H and 13C enhancements increased by 40% and 50%, respectively, at 5 teslas and 1.2 Kelvin.
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
It's freaking hard to examine proteins closely in their native habitat. With the help of very clever magnet instrumentation, University of Texas scientist Kendra Frederick is up for the challenge.
This week at the lab our new chief scientist is on the road, connecting the dots that are the National MagLab’s many instruments, techniques and experts.
Physicist Laura Greene, who was named the lab’s chief scientist last year, traveled from the lab’s Florida State University headquarters to the University of Florida in Gainesville, home to two of the lab’s seven user facilities: the High B/T Facility and the Advanced Magnetic Resonance Imaging and Spectroscopy facility (AMRIS).
Greene (pictured above left with Tom Mareci and Joanna Long of AMRIS) will learn about the special capabilities the facilities offer, including dynamic nuclear polarization (DNP), a promising technique under development at AMRIS and at the MagLab’s Tallahassee-based Nuclear Magnetic Resonance Facility. More familiar to biologists and chemists, DNP may also be a powerful tool for condensed matter physicists, said Greene. President-elect of the American Physical Society, Greene says a big part of her MagLab job will be identifying and building these types of fertile, cross-disciplinary relationships.
When scientists learn from colleagues at a different facility or lab about the research they are working on it, "People are astounded and excited by it," said Greene. "But then they go back and they’re busy. So it’s going to be my job to help keep the flywheel going … to keep it as single MagLab, make sure we learn from each other."
Greene hopes the connections she is fostering will result both in more scientific publications authored by MagLab staff from multiple facilities as well as publications spawned by collaborations with other national labs and industry. Through her work with the Center for Emergent Superconductivity, Greene has close ties to both Brookhaven and Argonne national laboratories.
Photo by Elizabeth Webb / Text by Kristen Coyne
Dynamic nuclear polarization (DNP) coupled with solid state NMR can provide orders of magnitude enhancement to normally weak NMR signals, thereby enabling the study of inherently dilute proteins such as membrane proteins. Here we demonstrate a new approach to obtain DNP signal enhancements of membrane proteins by utilizing spin labeled lipids as the polarization agents. This strategy results in more than 2x in signal enhancements of a membrane protein when compared to standard DNP sample preparation techniques.