10th Berg Symposium celebrates undergraduate researchers

Undergraduate students Thea Spellmeyer and Ruoyun Xu were selected as Berg Scholars at the 10th Annual John Berg Chemical Engineering Undergraduate Research Symposium Poster Session.

Since it started in 2015, the Berg Symposium has become a celebration of the undergraduate research experience. Chemical engineering undergraduate students who conducted research during the previous academic year or summer are invited to present a poster.

"By giving students the opportunity to practice their scientific communication skills, the Berg Symposium dovetails nicely with the department's Chemical Engineering Summer Scholars (ChESS) program," says Bob Tilton.

The Department of Chemical Engineering established the Berg Symposium following a generous donation from John Berg ('60), Rehnberg professor of chemical engineering at the University of Washington. "We felt it was important to honor his legacy as a bachelor's degree alumnus, and his highly accomplished research career, by doing something significant to enhance the undergraduate research experience here at Carnegie Mellon," says Tilton, Chevron professor of chemical engineering.

From among 25 students presenting posters this year, Spellmeyer and Xu were selected as top presenters by a volunteer judging panel made up of Ph.D. students and postdoctoral researchers.

The Department of Chemical Engineering provides travel and conference expenses for the Berg Scholars to participate in the Undergraduate Research Poster Competition at the American Institute of Chemical Engineers (AIChE) Annual Student Conference. The experience of presenting their work at a national conference is often a key step on a student's path toward graduate school or industry.

"AIChE truly opened my eyes to the breadth of research problems I could tackle with my background in chemical engineering," says Neha Nagpal ('21). Nagpal is currently pursuing a Ph.D. in chemical engineering at the University of Michigan. She was selected as a Berg Scholar in 2019.

The Berg Symposium was her first opportunity to distill and present her work with Tilton and Bhagyashree Lele ('15, '20). "The opportunity taught me important presentation skills and helped me gain immense confidence in my ability to not only conduct research but also to convey it well," says Nagpal.

"The capability to clearly communicate scientific ideas and the impact of my research, whether speaking with peers or mentors, will undoubtedly help me throughout my future training and beyond," adds Shawn Noronha ('24). Noronha, who was selected as a Berg Scholar in 2022, is pursuing an MD/Ph.D. at Tufts University.

When he attended the AIChE student conference, Noronha saw concepts that he learned about in his classes applied to real-world problems. "Researchers were presenting technologies or discoveries that would soon, if not already, improve people's lives," he says.

"Chemical engineers, across industries and academia, do incredible science," says Jennifer Lott ('18). "The ability to communicate that science and why it matters in a clear and concise manner can really set you apart and demonstrate your technical leadership." Lott is a senior scientist at Bristol Myers Squibb.

When she traveled to the AIChE student conference as a Berg Scholar in 2016, Lott saw that the experience was about more than showcasing her own work. "National-level conferences are also opportunities to network with others in your field and keep up with the latest technologies and methodologies," she says.

Lott is one of several Berg Scholars who have won prizes in their disciplines at the AIChE Undergraduate Research Poster Competition through the years. She was awarded 3rd place in the Separations category in 2016.

2025 Berg Scholars

Thea Spellmeyer

Poster: Sterilization of electrospun soy protein fibers loaded with extracellular vesicles

Thea Spellmeyer is part of a project to expand the therapeutic potential of soy protein fibers for wound healing. Her research advisor, Phil Campbell, works with soy protein because it interacts with human cells to support skin cell regeneration. It is also biodegradable, affordable, and scalable.

Researchers in the Campbell Lab are adding extracellular vesicles (EVs) that signal faster growth, with the goal of stimulating faster healing. Spellmeyer set out to determine the shelf life of the extracellular vesicles once embedded in the soy protein fibers. When she started her first tests, she realized that every sample was contaminated.

"We had recently changed our process of making soy protein fibers to use water instead of alcohol for the solvent," says Spellmeyer, "and we didn't anticipate how much that would increase the contamination risk."

The nano-scale soy protein fibers are made in a process called electrospinning. "We make a liquid polymer solution and use an electric field to draw it out of a needle to a collector. In this process, the polymer chain whips around and the liquid solvent evaporates, leaving just the solid fiber behind," explains Spellmeyer. The alcohol solvent they were using, however, broke down the extracellular vesicles, so they switched to water.

When Spellmeyer discovered that this led to widespread contamination, she refocused her summer research project to evaluate different sterilization methods. Working in a wet lab for the first time, she learned cell culture, scanning electron microscopy, and cell metabolism assays, among other techniques.

"It was challenging to pivot my objective several weeks in, but finding a solution for the contamination issue is critical for the overall project to advance," says Spellmeyer. Based on her results, antibiotic treatments and ultraviolet light treatments show the most promise as sterilization methods.

Ruoyun Xu

Poster: Post polymerization treatments for tuning equilibrium moisture adsorption of whey protein copolymer

Ruoyun Xu and her research advisor, Daphne Chan, are engineering protein to make usable protein copolymer. The protein copolymers available today adsorb water, which changes their mechanical properties and limits their use as a sustainable alternative to plastic.

"Think of plastic packaging, for example," says Xu. "You don't want it to swell because of moisture in the environment, and you also need it to remain strong enough that it can't be crushed easily."

Xu is investigating treatments that alter the secondary structure of the protein and decrease the amount of water it adsorbs. "We want to change the way the protein aggregates so that it has a more ordered secondary structure, with its hydrophobic groups on the outside and its hydrophilic groups hidden on the inside," says Xu. For the project she presented at the Berg Symposium, Xu prepared and tested 36 chemical treatments, including combinations of organic solvents, acids, bases, and heat treatment.

Planning to examine microscopic properties later in her research, Xu turned to journals to help her understand the foundational principles at the micro scale. "It was confusing, sometimes, when my data weren't behaving like the journals said. Then I realized it could be due to differences in the experimental conditions," remembers Xu. "There were also times when my data was justified by the journals, and that was pretty fun."

Xu found that the pH of the organic solvent mixture was the dominant treatment factor to reduce the amount of moisture adsorbed by the copolymer, when compared with an untreated sample.

Reflecting on her experience conducting research as a first-year student, Xu says, "I appreciate how Professor Chan gave me the opportunity to directly work with her and continues to give her time and energy to train me to become a good researcher."

Prior Berg Scholars

2015

Alexandra Cerny

Himali Ranade

2016

Tamara Amin

Jennifer Lott

2017

Yue Han

Siying Li

2018

Dhruva Byrapatna

Ian Tilton

Sophia Wang

2019

Keya Ganatra

Neha Nagpal

2021

Benjamin Pavlat

Ketong Chen

2022

Jamie Joseph

Shawn Noronha

2023

Linda Liu

Tal Dassau

2024

Juhee Park

Yansi Foong

Irene Cui