Timothy Manning Swager, the Inventor

By Bevin P. Engleward
MIT Superfund Research Program Director
Jan 07, 2021

This blog is to celebrate the accomplishments of Timothy M. Swager on the occasion of his being named a Fellow of the National Academy of Inventors. Tim is the John D. MacArthur Professor of Chemistry and the Director of the MIT Deshpande Center for Technological Innovation. Tim is also a project leader for the MIT Superfund Research Program, a program that is focused on environmental health with an emphasis on serving environmental justice communities.

If there is one thing that stands out about Tim, it is his imagination. He has a flare for the creative design of materials that sense things. He is an ‘outside-the-box’ thinker with a toolbox of materials with different physical characteristics that he manipulates for completely new applications. He is unparalleled when it comes to harnessing chemical phenomena for sensing schemes. Give him a box of chemicals and he will turn it into some sort of clever recognition element.

DiagramDescription automatically generatedA favorite example is his use of tiny droplets as sensors. Who would have thought that tiny micron-scale droplets could be used for their light refraction capabilities as molecular sensors? The way this works is that you start with two oils that don’t mix with water and only mix with each when they are hot. Adding this hot mixture to water, droplets are formed, that after cooling, are made up of two halves, like hemispheres of the earth, or like poke balls! The dense oil droplets sink and so the “Janus” (the two-faced God that Janus is named after) droplets sit flat like little boats floating in water. If you shine a light on them, the light goes straight through, unhindered. While this is already pretty neat, the real innovation comes when you decorate the top half of the droplet by adding stuff that binds super-tightly to target molecules.

If two droplets try to grab the same thing, the top halves tip toward each other in a tug-of-war. The end result is that now light doesn’t go straight through anymore, but instead bounces in other directions. What is really cool is that if you have a field of droplets and they are tugging at each other, you can tell that this is happening using a smart phone. Voila! Now you have a molecular sensor that you can use with your smart phone! The idea is brilliantly simple and broadly useful. The method even has the potential to be useful for home-tests for things around us, or even inside of us (e.g., a test that can be used as a diagnostic using a finger prick of blood).

But this is just one example! There is also “Fido,” named after the dog because dogs have amazing senses of smell. Tim is very passionate about conductive polymers and has used them to amplify signals. Using conductive fluorescent polymers (polymers that glow after having light shined on them), Tim created a mind-bogglingly sensitive detector for trace levels of explosives. The same way scents coming from afar tease our noses, this device can sense wafting tendrils of scents. You can wave the sensor in the air and it can sense plumes in the breeze emitted from explosives far away. It’s even better than a dog!

Tim is also a leader when it comes to carbon nanotube sensors. He figured out ways to sense chemicals associated with food products that are past their prime (food spoilage). The carbon nanotubes are used to create a wireless gas detector that transmits signals to a smart phone. Basically, you start with a small piece of paper and a special printer. After printing ‘wires’ as strips of metal on the paper, you add the special carbon nanotubes between the ends of two wires. If the carbon nanotubes stick to their target, the current changes and this change can be sensed by a smart phone (it is kind of like wireless charging, but in reverse). The end result is a near field communication device that is cheap and easy to distribute.

DiagramDescription automatically generatedIn another exciting application, in his role as Leader of Project 2 for the MIT Superfund Research Program, Tim and postdoc Maggie He created a carbon nanotube sensor for N-nitrosodimethylamine (NDMA). NDMA is a carcinogen that can be found at Superfund Sites, and in drinking water and food. More recently, NDMA has been discovered to be a contaminant of commonly used drugs, such as Zantac, Valsartan, and Metformin.

These are just three of many examples of really cool ways to sense things, whether it be something in the air, something in water or even something inside of you!

Despite his accomplishments, Tim is approachable and unassuming. He loves to bounce ideas with people and is constantly throwing out ideas to his colleagues to see what catches. He also thrives on talking with people who think differently from him, whether it is science or other things. When there is a new kid on the block, he reaches out to welcome them and to muster ideas for collaborations. Tim thrives on in the MIT ecosystem of smart minds ready to run with ideas. If Tim asks a question that someone doesn’t know how to answer, rather than judging, he seeks to understand what they do know about. He is quick to appreciate that everyone has something to offer, so you just need to figure out how to match people with project opportunities. People who work with Tim feel lucky, and the members of his team appreciate that he has an eye on their future. For those headed for independence, he is generous with ideas, leaving room for his academic progeny to thrive. A former postdoctoral scholar in Tim’s lab, Julia Kalow, now an Assistant Professor at Northwestern University, had this to say about Tim, “Tim has the unique ability to apply his synthetic intuition to problems across chemistry, engineering, and physics, designing and building molecules that are both beautiful and functional. He can distill complicated concepts into elegant, clear explanations–a wonderful trait in both a mentor and a collaborator. And another invaluable trait for a mentor and collaborator: his awe-inspiringly fast email response time. I can’t find any examples where I had to wait more than 24 hours for a response, and usually, it’s less than 2!”

Tim also has been an influential scientist and mentor to his fellow faculty at MIT, with Jeremiah Johnson a fellow Professor of Chemistry saying, “Tim is a leading figure in the field of organic materials, and his work has inspired a generation of chemists working at the interface of organic synthesis and polymer chemistry. As my faculty mentor when I began at MIT, Tim always gave (and continues to give) candid, detailed advice with my best interest in mind. I would not be where I am today without him, and I look forward to continuing to learn from him throughout my career.”

Tim didn’t grow up thinking that he’d be an inventor, but rather he grew up thinking he’d be a rancher in Montana. He met his wife working a summer job at a nearby ranch and has always put family first. To Tim, family is the most important thing, above all else. That said, his biggest flaw is that he is addicted to work. He says to his postdocs, “you’d be surprised how well you can do with only 4-5 hours of sleep. Don’t worry, you’ll get used to it. It’s just conditioning, you’ll be fine!”