Sarah St. Angelo

Sarah St. Angelo


by Christine Baksi

Focus on Faculty is a new regular Q-and-A series. In this inaugural piece, Sarah St. Angelo, assistant professor of chemistry, discusses the importance of interdisciplinary studies in the sciences, meaningful encounters with her idol and what it means to mentor and motivate students. 

You’re an advocate for interdisciplinary pursuits in the sciences, as demonstrated by Rush Hour, a lunchtime lecture series you helped launch in 2009. This semester, your inorganic chemistry class has become a living laboratory for interdisciplinary perspectives, with four international students and two double majors in surprising areas – philosophy and archeology. How has the class makeup enhanced your teaching and the students’ experience?

The variety of student interests provides opportunities to find new meaning and contexts. As seniors, the students are really figuring out what they want to pursue after Dickinson and how to use their Dickinson experiences in the future. Even if a student intends to be a chemist, there are lots of paths to follow, and in this class, there are students interested in engineering, nanotechnology, pharmaceuticals, beauty/fragrance and more. It’s important to learn about their interests and try to make what we do in class as relevant as possible. I don’t think students realize how much they can teach professors just by sharing their interests and figuring out different ways to discuss a topic.

What are your current research interests? 

My students and I have been using the teas of different plant leaves to help make nanoparticles. This is interesting because the plant teas let us avoid some hazardous materials and because these complex mixtures can produce unusual nanoparticle compositions and shapes. In the “nano-world,” size, shape and composition determine the properties of the material—and often the nanomaterial has vastly different properties than a big chunk of the same material. Color is one of the most obvious changes—we think that gold is always gold, but when it is on the nano-scale, it is red, purple or blue, depending on the size and shape. Silver can be orange, and our copper oxide particles are fluorescent yellow.

With [student researcher] Katelyn Cohen ’12’s copper oxide particles, we are trying to control the synthesis so we can vary the particle sizes. She is working to characterize them so we can understand how the synthetic conditions affect the size. We have some evidence that synthetic conditions change the color of the fluorescence, and this is a result of changing the particle size. While we have a lot of work to do before we would look for real applications, copper oxides are used for catalysis—making energetically expensive reactions cheaper.  

The American Chemical Association (ACS) deemed 2011 the Year of Chemistry, which Dickinson celebrated in many ways—most notably with a lecture by someone you idolize, Harvard professor George Whitesides. What did his visit mean to you and Dickinson science students?

I was initially star-struck because this is a scientist whose work I have followed for about 15 years. I met him briefly and saw him speak at an ACS meeting in 2010, and I knew he had to come to Dickinson. At the ACS meeting, he spoke on what was a new topic for me—the low-cost diagnostic devices that were the subject of the Priestley Lecture. He was gracious at the conference, but I had no idea that his visit would be as enchanting as it was.

Whitesides knew the questions to ask each of us. He seemed so interested in the faculty, students and administrators and he navigated conversations so that we were each looking at ourselves, our goals and our beliefs. I think we initially wanted to know more of his story and perspective, but he always seemed to steer the discussion back to the people with whom he was speaking. It was masterful and instructive: no one else’s path is as important as one’s own path. The more each of us works with purpose, the more good each of us is likely to do. We learned about his work and the amazing potential for world health that his paper diagnostic devices hold, but I think he also made us look to our own potential.

Students sing your praises. Katelyn Cohen refers to you as “the definition of a great mentor” and says, “she allowed me to reach far beyond my current knowledge and taught me how to apply the things I learned in class to a research environment. She got me excited about science.” What does student feedback like this mean to you as an educator? 

It is humbling. I know what some of my favorite teachers and professors have meant to me, and if I can be important in a student’s life, I have accomplished something. Whitesides asked us, “Can you do work at Dickinson that could change the world?” He was referring to research and probably comparing our research capabilities to Harvard’s—the manpower, equipment and budgets are very different, but great ideas can come from anywhere. If someone like Katelyn believes she can reach farther or is more excited about science because of something I did, then what we do at Dickinson changes the world every day.

Published February 22, 2012