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A powerful bond

Myrna and Andre Simpson are revolutionizing the way environmental researchers ask their most important questions.

Andrew Westoll
Simpson lab NMR

One of two nuclear magnetic resonance (NMR) spectrometers at UTSC's Environmental NMR Centre. These machines are among the most powerful analytical tools in science.

In the basement of the Science Research Building at the University of Toronto Scarborough, behind a heavy steel door and surrounded by several feet of reinforced concrete, sit two hulking gods. Upon entering their lair, visitors are encouraged to relinquish keys, cellphones, pocket change and even wedding bands—not as some kind of sacrifice, but simply as a safety measure. The magnets inside these high-tech behemoths are so powerful they could scramble your iPhone and rob you of your jewellery at a distance of six feet. Every five minutes or so, one of them emits a startling blast of exhaust so volcanic in nature the visitor feels as if he is standing atop Mount St. Helens in early May 1980.

This room is the Environmental Nuclear Magnetic Resonance (NMR) Centre at UTSC. These imposing machines are NMR spectrometers. They have the divine ability to peer deep into the soul of matter, to reveal the nature of the bonds between individual atoms. And environmental researchers Myrna and Andre Simpson are their masters.

NMR spectroscopy is the most powerful analytical tool available to the scientific investigator. It involves two essential steps. First, researchers place their study samples within the magnetic field of the massive magnet, which causes the nuclei within molecules to align themselves according to their characteristic molecular environments. Then a specialized probe pulses electromagnetic radio waves through the aligned nuclei and the system records their responses. The result is a three-dimensional map of the sample that reveals—to the highly trained eye—which atoms are present, which atoms they are bonded to, their bond distances, and even how different molecules in the sample interact with each other.

Up until about 15 years ago, NMR was mostly the exclusive domain of chemistry departments. Few ecologists or biologists would have considered this technique, as it wasn’t optimized for the sorts of complex, heterogeneous samples—like soil—that they needed to study. But then a small group of environmental scientists began wondering how the power of NMR might be brought to bear on environmental problems.

“NMR had the potential, but it really wasn’t tailored,” says Andre Simpson, who along with Myrna was doing his PhD among this group of NMR pioneers in the late 1990s.

At the time, NMR only worked on “single-phase” samples—that is, samples that were either all liquid, all solid or all gel. What budding environmental scientists, like the Simpsons, needed was the ability to perform experiments on “multi-phase” samples.

“Consider a contaminant spill in the environment,” explains Andre. “The contaminants are in a liquid state. But then they start to stick to the soil and as time passes, the soil becomes a bit like a gel. Then, a few days later the soil becomes solid. Back when we were doing our PhDs, we couldn’t follow these processes with NMR because we couldn’t do experiments on things that went from liquids to gels to solids. We couldn’t follow the bonds.”

Now they can.

Over the last 10 years, the Simpsons—in collaboration with their industry partner, Bruker BioSpin—have developed the world’s first NMR probes for heterogeneous samples. They call the new technology “comprehensive multi-phase NMR,” and with it they are putting the unparalleled power of NMR spectroscopy into the hands of environmental scientists who are working on some of the most pressing challenges of our time.

“The probes are really the brains of the system,” says Myrna. “Most chemistry departments have four or five probes. We have about 20. That’s what makes our facility so unique. We’ve got the hardware to conduct a wide diversity of experiments.”

Through a combination of major funding from the Natural Sciences and Engineering Research Council of Canada (NSERC), the Canadian Foundation for Innovation (CFI) and the Ontario Research Fund (ORF), and with deeply discounted equipment and donations from Bruker BioSpin, the Simpsons founded the Environmental NMR Centre in 2004. Home to more than $5 million worth of state-of-the-art technology, the centre also houses two cutting-edge NMR spectroscopes and is the only facility on the planet dedicated solely to environmental NMR studies.

The Simpsons are a scientific tag team with a unique division of labour. “Andre focuses more on method development,” says Myrna, “whereas I focus more on what we can do with these methods to answer questions about climate change, pollution and health.”

So, while Andre continues his development work, Myrna’s expertise in applying NMR to environmental problems are called upon by scientists, governments and organizations worldwide. She is working with researchers in Israel to determine whether waste water might be reclaimed for crop irrigation; in the United States on a long-term study in the Harvard Forest, an ecological research area managed by Harvard University; and with Agriculture and Agri-Food Canada (AAFC) on a groundbreaking carbon sequestration study. She is also close to completing a grant agreement for a study of deep subsurface organic matter with the Nuclear Waste Management Organization (NWMO) of Canada.

Meanwhile, the Simpsons collaborate with numerous UTSC researchers from a diversity of fields. Professors Malcolm Campbell (plant biology), Rene Harrison (bone-wasting disorders) and Kagan Kerman (neurodegenerative diseases) are all engaged with the Environmental NMR Centre, either directly or through the work of their graduate students.

But among all the areas the Simpsons are working in, Myrna is most excited about the arcane, yet quietly booming, field of environmental metabolomics. “We’re trying to develop an early warning system for environmental health,” she says. “We use NMR to measure the metabolic profile of model organisms to determine if they are under some sort of stress. Our methods are so sensitive that we can tell if an earthworm is stressed out within 48 hours of exposure to a toxic chemical in the environment.”

It’s an approach that also has huge potential as a discovery tool.

“With many new and emerging contaminants, we don’t know the toxic mode of action,” says Myrna. “We can use environmental metabolomics to show the mechanisms by which these novel chemicals may be disrupting the organisms.”

The Simpsons share a powerful bond in science as well as in their personal lives. They met in 1997 at a conference in Los Angeles and they are now married with two-year-old twins.

“We talk about our work even when we’re not at work,” says Andre. “And that’s important, because we are developing new technologies while simultaneously applying them to environmental questions in new ways. Without [unlimited time to talk], it would be really difficult to move both fields forward at once.”

In addition to raising children, running a bustling lab and developing a research revolution, this year the pair will also edit a book on environmental NMR.

Myrna and Andre’s long-term goal is to develop their lab into a national Environmental NMR Centre, where researchers from across the country and around the world can perform their own experiments. But herein lies one of the unexpected challenges of building a career at the bleeding edge of scientific innovation.

“Who’s going to train them?” asks Myrna of these visiting researchers. “Unfortunately, there is a huge gap between people who know how to use these instruments and those who understand environmental samples.”

Until the field they founded catches up with them, the Simpsons are content to continue pushing it ahead.

“We now have the technology to observe the bonds in an intact heterogeneous sample at atomic resolution,” says Andre. “The implications of this are huge and we’re only beginning to scratch the surface.”

To learn how you can support cutting-edge research at UTSC, contact Georgette Zinaty, executive director of development and alumni relations, at gzinaty@utsc.utoronto.ca.