In Diagnostics, Seeing is Believing

On February 20, at 11 am in Evanston, you will be able to see the future.

Well, almost. At an upcoming Junior Science Cafe event [4], Northwestern University professor Tom Meade will explore hand-held detectors that rapidly test food and water for contamination, or our bodies for viruses, or identify genetic predisposition to certain diseases. He’ll show how he and other researchers are creating highly accurate imaging techniques that will provide three-dimensional images of what goes on inside our bodies,

Tom Meade’s research involves nanotechnology, the science of building stuff from single atoms and molecules. The Wilmette resident is the Eileen Foell Professor in Cancer Research in Northwestern University’s Weinberg College of Arts and Sciences and Feinberg School of Medicine.

He is a chemist, teacher and entrepreneur. But mostly, he’s a storyteller who enjoys sharing his work. We asked him for a preview.

So, what’s the future of diagnostics?
These days, a lot of diagnostics still rely on measuring bulk properties, big things like height, weight, and blood pressure. We can get a little more sensitive by measuring levels of things in blood, like cholesterol. But still, most current diagnostics find things after symptoms emerge. And by then, it’s too late.

Tom MeadeIt reminds me of the “idiots lights” in my old ‘68 Pontiac. These were warning lights on the dashboard of the car that told you if the car was too hot. But by the time they started glowing red, there was smoke coming out of the engine.

My field is called nanodiagnostics. Our goal is to alert people to danger before there are symptoms, often by measuring very minute amounts of things very accurately. That might mean testing for tiny bits of genetic code, such as in our test for cystic fibrosis, or it might mean testing for subtle chemical changes. But there are other kinds of nanodiagnostics that promise improvements too.

For example, nanotechnology can offer a leap in the quality of imaging techniques, and not just a small one— it could be a game-changing event. Take our recent MRI study with something called nanodiamonds. Nanodiamonds are molecules built in the shape of a pyramid. They are utterly unique among nanoparticles. A nanodiamond is like a cargo ship— it gives us a nontoxic platform upon which to put different types of drugs and imaging agents.

In this study, we loaded nanodiamonds with the standard contrasting agent used in MRIs to help show what’s going on inside the body, and we got remarkable results. It is far more sensitive than anything else I've seen – 15 times more sensitive. And we needed to use far less of the standard agent, which means it should have fewer side effects too.

You’ve published scores of papers and started four companies. How do you keep coming up with new ideas?
I’m a scientist first. It always starts with a basic science question. We need basic science in order to understand fundamental principles or mechanisms, whether it’s learning about an atom or the farthest galaxy.

Applying what we learn and creating a new product is secondary. For example, the first company I started grew out of trying to figure out how electrons flow through DNA. Okay, let me back up for minute here and define a few terms.

Electrons are the negatively charged bits in atoms. When they flow through anything, that’s an electric current. And you’ll recall that DNA comes twisted together in two strands. So, during this research on how electrons flow, I noticed a faint electric current when both DNA strands where there. But with a single strand – nada.

I realized this meant that we could create an electronic diagnostic chip. Basically, here’s how it works. We put one strand of DNA on a probe, take some blood from someone and wash it over the probe. If the “mate” from the DNA is in the blood, they find each other, and there’s enough current for us to know it’s there.

Right now, we have products that use this technology to test for cystic fibrosis and help doctors figure out the right dose for drugs that thin your blood. But someday, we hope to predict many conditions, perhaps even at birth, when there’s plenty of time to prevent symptoms from even emerging. That’s the dream.

Learn more at a Junior Science Cafe event featuring Tom Meade [4] on Saturday, February 20th from 11 AM -12:30 PM at BooCoo Cafe, 1823 Church Street, Evanston.

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