NMRFAM Installs New 1.1 GHz Magnet

This winter, the team at the University of Wisconsin’s National Magnetic Resonance Facility at Madison (NMRFAM) welcomed a new member: a high-powered, superconducting, 1.1 gigahertz (GHz) magnet.

The magnet will be used by researchers to investigate molecular structure, motion, and interactions at higher resolution and sensitivity. Funding for the magnet comes from a National Science Foundation Mid-scale RI-2 Consortium award, and supports using the magnet for research in the biochemical, chemical, and physical sciences that requires ultra-high field nuclear magnetic resonance (NMR).

From left to right: Alex Paterson, PERSON, Chad Rienstra, Katherine Henzler-Wildman, Songlin Wang, and Paulo Ricardo in front of NMRFAM's new 1.1 GHz magnet.
From left to right: Alex Paterson, Boden VanDerLoop, Chad Rienstra, Katherine Henzler-Wildman, Songlin Wang, and Paulo Pinheiro stand in front of NMRFAM’s new 1.1 GHz magnet.

“What’s so unique about the 1.1 gigahertz magnet,” says Katherine Henzler-Wildman, co-director of NMRFAM and professor in the UW–Madison Department of Biochemistry, “is that experiments that were impossible before are now possible.”

NMR uses strong magnets to map the orientation of nuclei in molecules and can be used to identify molecular conformations, interactions, movement, and structure. One of the strengths of NMR is that it can be used to analyze samples at physiological pH and temperature, rather than using sample preparations that may alter molecular conformations and interactions. However, the technique has some limitations. Effective data collection often requires large quantities of a sample, and the process can take days or weeks, making NMR unsuitable for compounds that degrade quickly.

The new magnet eliminates these limitations for many compounds.

Alex Paterson, a materials scientist at NMRFAM, explains, “There are experiments that would have taken weeks to run, maybe longer. And now, we can do those [experiments] sometimes up to 30 times faster. What would have taken two weeks now takes one day. That means that we can analyze unstable samples that might degrade after, say, 10 days. We can distinguish very small differences between similar chemical environments, which means that we can analyze larger and more complex compounds.”

The new addition is one of only three GHz-class magnets in the United States. It is also the only one with a wide range of solid-state NMR probes — which allows the research facility to accommodate a variety of research questions. The 1.1 GHz magnet joins NMRFAM’s other magnets, ranging from 500 to 900 megahertz (MHz), increasing the facility’s capacity as a resource for researchers across the country.

The spectra (right) for the enzyme TOHO-1 beta-lactamase (left) demonstrate improved resolution and sensitivity of data at 1.1 GHz compared to 600 megahertz (MHz). At 1.1 GHz, the signals are narrower, allowing for clear differentiation among peaks which give researchers more information about the sample. At 600 MHz, some signals in close proximity to each other blend together. Data were collected at NMRFAM; the associated research project is in collaboration with University of California-Riverside scientists Leonard Mueller, a professor in the Department of Chemistry, and graduate student Christopher Williams.

NMRFAM is part of a consortium of facilities known as Network for Advanced NMR, or NAN. Through NAN, UW–Madison, along with University of Connecticut and University of Georgia, gives researchers nationwide access to NMR analysis.

“NAN serves as matchmaker to align the most meritorious projects, the ones that are both scientifically significant and doable, with facilities that can support the work,” explains Chad Rienstra, co-director of NMRFAM and professor in the UW–Madison Department of Biochemistry.

In fact, the new magnet is one of two to be installed at NAN facilities: the University of Georgia will also house a 1.1 GHz magnet. The two magnets will serve different purposes, however — NMRFAM’s magnet will be dedicated to solid state NMR, while the University of Georgia’s will be dedicated to analyzing samples in solution. Solid state NMR allows researchers to analyze solid compounds without needing to dissolve samples in solution, which can be especially useful to scientists studying materials like crystals and glass, as well as complex compounds whose properties change when dissolved.

“Having the dedication to solid state NMR means that we as a facility can offer more uptime running experiments for the research community,” says Paterson. “We’re not taking it down to recalibrate, and we’ll spend less time on maintenance. The facilities all work closely together to make sure that researchers are sending their samples to the best facility for the data they need.”

The new 1.1 GHz magnet is now up and running. The team at NMRFAM has run several preliminary experiments as they calibrate the powerful tool, and they are excited to collaborate with researchers to explore the molecular world with new, sharper clarity.

Written by Renata Solan.