Single-sided NMR

One of our magnets being used to measure paint layers in an object at the Harvard Art Museums in 2015.

One of our magnets being used to measure paint layers in an object at the Harvard Art Museums in 2015.

What is NMR?

Nuclear magnetic resonance (or NMR) helps chemists determine the structure of small molecules, biologists determine the three-dimensional shape of proteins, and physicians locate and characterize anatomical aberrations. (This last one comes courtesy of NMR’s better-known sibling: MRI. At heart, though, they’re really the same thing.)

Despite NMR’s ability to solve many chemical and medical problems, it comes with several costs. Large devices used in traditional NMR are expensive, both to acquire and to maintain. They are restricted by the size and shape of samples they can accommodate. Lying in an MRI magnet is uncomfortable and, frankly, unpleasant. And because they are fixed in a dedicated lab space, magnets used in NMR aren’t ideal for measurements done out of a traditional lab setting (e.g., on historical buildings).

Mobile NMR

At William & Mary, the Meldrum group works with small, portable, cheap(er) magnets that circumvent many of these drawbacks. Importantly, these magnets detect signal outside of their housing, rather than within it. Consequently, researchers can take arbitrarily sized samples and put them on top of, rather than inside of, the magnet. This opens up a world of NMR analysis of objects that either can’t or shouldn’t be destructively sampled for traditional NMR measurements. The major downside is the loss of some chemical information, but the upside is a wealth of information on the physical state of different materials, useful for understanding materials ranging from industrial coatings on surfaces to priceless works of art.

Current projects

The Meldrum group works in two main areas of single-sided NMR: materials analysis and methods development.