All scientific discoveries, large and small, start with one common goal—to advance knowledge, be it about our bodies and health, our environment, or even our universe. But the most exciting discoveries, built on years of research and collaboration, fundamentally change how we understand our world.
In a special summer series, Science in Society will talk with five Northwestern scientists whose work is already changing their fields, and could potentially change our lives.
Chad A. Mirkin is the director of the International Institute for Nanotechnology and the George B. Rathmann Professor of Chemistry, as well as a professor of chemical and biological engineering, biomedical engineering, materials science and engineering, and medicine at Northwestern.
The Wilmette resident holds more than 360 patents and applications, and is the founder of three local companies that are commercializing nanotechnology applications. Currently a member of President Obama's Council of Advisors for Science and Technology, he holds more than 60 national and international honors for science and technology.
And he still makes time to teach freshman chemistry courses. We caught up with the 46-year-old dynamo earlier this summer.
You study nanoscience. What does that mean?
We study ways of making highly miniaturized structures and explore how and why they are different from their bulk counterparts. Gold is a beautiful example. When it’s miniaturized, it is red in color. Almost all of the chemical and physical properties of a material change when miniaturized to the nanoscale.
By modifying nanostructures, we can develop all kinds of applications that take advantage of their unique properties.
How do you modify them?
We develop chemistry for attaching substances to the nanoparticles. For example, we can attach fragments of DNA or proteins to make them very specific for disease markers. Think of it as a chemically programmable (by virtue of sequence), very specific type of nano-Velcro®.
Is there something in your work of which you are most proud?
In 1996, we were the first to connect DNA to gold nanoparticles. We published this discovery in a paper in Nature, one of the most highly respected science journals, and it created a new field. Several important aspects marked this discovery.
One breakthrough was structural. By attaching DNA to gold nanoparticles, we could now make programmable, self-assembling structures. DNA is comprised of two strands that recognize each other and attach to each other in very specific ways. You can think of it as making very specific zippers.
So, we make a specific sequence of DNA and put it on gold nanoparticles. Then, when we add that to a solution, it finds other particles with complementary DNA and zips them together to make a larger material with properties that derive from the types of particles used and their placement in the extended structure.
It’s man over nature. We can literally chemically program the formation of a three-dimensional material with the properties we want for a desired application.
It’s a natural way of developing new medical diagnostic tools. We can create particles with DNA sequences that can assemble in the presence of DNA strands associated with a specific disease. In the case of gold, when they do this there is a spectacular red-to-blue color change. Our first company, Nanosphere, headquartered in Northbrook, now uses these particles and concepts to create diagnostic tools for many diseases, including cystic fibrosis, flu, cardiovascular disease, and different forms of cancer. Many of these are FDA-cleared and will be used by doctors at the point-of-care to diagnose disease.
We’ve also learned that the same particles can be designed to enter cells easily, and used as genetic switches. This could have implications for creating gene therapies for cancer, Alzheimer’s disease, and HIV, to name only a few.
What are you working on now that most excites you?
Actually, gene therapy. There’s a race right now. And nanomaterials are likely to be the winner because we can build structures from the bottom up. We can design and synthesize materials that are highly effective with fewer or no side effects. The technology is extremely important and part of the most recent company we started, Aurasense.
How did you get interested in nanotechnology?
When I was starting my career, we had just gone through the age of miniaturization, which fueled the microelectronics industry. Such efforts made it possible for almost everyone in developed countries to have a desktop computer. At the time, nanoscience was the great frontier. Chemical ways for making nanostructures and analytical tools for characterizing them had to be developed. I decided to try to take on this challenge and help drive the field. We helped initiate and build the largest nanotechnology effort in the world at Northwestern, which is now known as the International Institute for Nanotechnology (IIN).
What advice would you give young people?
Consider a career in science. If you are articulate and creative, there’s nothing better. Don’t be intimidated, it’s not as hard as you think.
How or when did you fall in love with science?
For me it was pretty late. As a kid, I liked science but I didn’t love it. I was a gym rat and spent most of my time on the basketball court. Then, in college, I spent ten weeks in a graduate lab at Penn State through a National Science Foundation summer program.
In school, you spend all your time learning about things from textbooks. It’s sometimes boring but necessary. But in a lab – when you discover it, when you explain it, when you find something brand-new – there’s no greater high. That’s what keeps me coming back.