Just because something can’t be seen doesn’t mean it can’t be studied.
Enter nanotechnology—miniscule structures that scientists can engineer to study and solve microscopic problems.
Jennifer Steele, Ph.D., chair and professor of physics, enjoys studying nanotechnology for this reason. "We're making a hammer for very specialized nails,” explains Steele. “We’re looking at a problem that needs a new tool, and we are designing a structure that will give us a better understanding of the problem and the solution.”
Steele’s lab is currently studying fluorescence resonance energy transfer (FRET), a technique that scientists can use to measure the relative distance between microscopic molecules—such as the proteins in our cells—that are mere nanometers or ångströms apart. FRET is able to do this based on the interaction between a paired set of fluorescent molecules. If the molecules are in close enough proximity, one molecule, the donor, will donate its energy to the other molecule, the acceptor, to create a fluorescent signal that gives off a bright light. "You can use this energy transfer as sort of nanometer rulers—very, very precise rulers,” Steele adds.
But, Steele says, that bright light isn’t always a strong enough signal. Her work focuses on amplifying that signal. Most of the current work regarding FRET focuses on using engineered nanoparticles that have a single, broad optical resonance that can amplify the signal from many different wavelengths, or colors, of light. However, Steele thinks that may be oversimplifying things. Her group of undergraduate researchers works to engineer nanostructured surfaces with narrow optical resonances that can move throughout the range of wavelengths of light. By doing so, they can better understand the physics of the process and thus be able to better amplify FRET’s fluorescent signaling.
To support her research, Steele has been awarded a three-year, $257,090 grant from the Division of Material Research of the National Science Foundation. The grant includes approximately $70,000 in new equipment as well as eight summer stipends for Trinity students over the next three summers. While COVID-19 has set Steele a few months behind schedule, she plans to get started with data collection in the upcoming spring.
“Because a lot of the work for FRET revolves around these structures that have the one optical resonance, and the structures we're making have a range of them, I felt like [other researchers] weren't capturing the entire picture,” Steele says. “And it's that drive to not let this question in your mind go that gives you the motivation to write the grant and then do the work. I think they're missing something in the interpretation, and we're going to find out."