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E.S. Freed and Charles O. Hill are pictured in a laboratory in Science Hall. The photo is in black and white and was taken between 1913 and 1915.

UT Alum Left Lasting Impact on Chemical Extraction

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E.S. Freed and Charles O. Hill are pictured in a laboratory in Science Hall. The photo is in black and white and was taken between 1913 and 1915.

Chemistry is frequently called the central science. Because it uncovers knowledge critical to the understanding of matter, it is important to a number of disciplines. Discoveries and innovation in chemistry can have far-reaching implications that last for decades. The great-grandson of alumnus Edgar Stanley Freed came face to face with this phenomenon when he began researching his family’s history.

E. Stanley Freed came to the University of Tennessee, Knoxville, in 1909. He joined the Department of Chemistry, earning a bachelor’s degree in chemical engineering in 1913. Freed then served two years as an assistant professor at UT, until beginning graduate studies at the Massachusetts Institute of Technology (MIT).

Freed received one of only four PhD degrees MIT awarded in 1918. In 1920, he began working in the New York laboratory of the Chile Exploration Company, and in 1922 he relocated to Chile.

Building a Legacy

By the time Freed arrived in Chile, the nitrate industry had been suffering for a number of years, due to the development of synthetic nitrate. The Chile Exploration Company sent Freed to an experimental plant for nitrate extraction working with caliche, a type of soil containing a variety of mineral deposits including nitrate salts. He was tasked with modernizing the industry by developing better, more efficient processes.

Upon his arrival, Freed realized little research had been done on the caliche itself and its chemical properties. He quickly began developing a body of knowledge that could be used to inform extraction methods. Over the course of his career, Freed and a number of additional researchers made advancements in mineral extraction from caliche.

By the mid-1940s, Freed had begun to pursue not only nitrates, but possibly useful byproducts. He would eventually be credited with developing the solar evaporation pond, a method that uses the natural process of evaporation in a series of open-air ponds to extract a variety of products.

Freed’s evaporation ponds became an industry staple and are still used today. This method has been used to efficiently recover nitrates, iodine, potassium, and even lithium. It is still considered a key element of production in industry, and contributes to a range of fields including pharmaceuticals, construction, and agriculture. Lithium alone has been used to power personal electronics, medical devices such as pacemakers, and electric vehicles. Freed’s development helped prop up a declining industry and simplified access to materials that have been used to create a number of elements of modern life.  

Preserving History

Book cover: Edgar Stanley Freed, Los Guggenheim y La Industria Del Salitre

Sebastian Freed-Huici began investigating his great-grandfather’s history in earnest at the age of 14. Freed-Huici had been taught that the nitrate industry in Chile collapsed due to a combination of the Great Depression and the creation of synthetic nitrate. However, he knew that Freed had been working in the industry up until his death in 1950. Unable to reconcile these differing timelines, Freed-Huici began digging into his family’s records, uncovering more of Freed’s story.

“My grandmother kept a folder about my great-grandfather with some newspaper clippings and other information about him,” said Freed-Huici. “She also had his diplomas from the University of Tennessee and MIT. After that, I looked for information about him online and then started calling historians.”

Freed-Huici eventually connected with a historian at the Archivo Nacional de Chile who had recently uncovered boxes of documents about and belonging to the late E. Stanley Freed. It was in communicating with the historian, Pablo Muñoz, that Freed-Huici learned of his great-grandfather’s achievements.

Galvanized by this discovery, Freed-Huici set out to share Freed’s story and, in the last few years, all that effort has begun to see results. In 2021, a book detailing Freed’s life and work was published. Edgar Stanley Freed, Los Guggenheim y la Industria del Salitre was written by Patricio A. Espejo Leupin and included images and documents provided by Freed-Huici. A second book, written by industry professional Beatriz Oelckers and titled El Hombre Que Más Sabía del Caliche en el Mundo, was published in August 2024.

Freed-Huici, now a PhD student in economics at the University of Chicago, said he was inspired by his great-grandfather and wanted to share his story.

“I realized that this is not a story of the past. It’s a story of the present, because all these systems are used today,” said Freed-Huici. “His legacy is alive, and I want people to know about it. For the 28 years he was in Chile, he never stopped working on this problem. He never stopped researching and experimenting and looking for answers, and I find that very inspiring.”

Remembering George K. Schweitzer

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Black and white headshot photo

It is with great sadness that the Department of Chemistry announces the passing of Professor George K. Schweitzer. The longest serving faculty member in the history of the University of Tennessee, Schweitzer will be remembered for his pioneering work in inorganic chemistry and radiochemistry, and by the thousands of students he mentored and taught.

Born in Poplar Bluff, Missouri, Schweitzer earned a BA in chemistry from Central College in 1945. He went on to graduate studies at the University of Illinois, where he was granted a PhD in 1948. Schweitzer moved to Tennessee to join the chemistry faculty in 1948 and in 2023 celebrated his 75th year of teaching at UT.

During World War II, Schweitzer investigated an element similar to uranium and his dissertation work has been described as an extension of the Manhattan Project. He said he came to UT because of its proximity to the Oak Ridge National Laboratory and its relevance to his research. Upon his arrival, Schweitzer was charged with establishing the PhD programs for Inorganic and Radiochemistry.

Schweitzer described his first day of teaching as “a hoot,” noting that, at 23 years old, he was convinced most of the students in his class were older than him. He enjoyed telling the story of that day, when he joined class and sat down to listen to the students discussing the new professor and what they expected him to be like. When the bell sounded for his class to begin, Schweitzer stood and introduced himself to his students, who all laughed.

At a time when the university was just beginning to develop its identity, Schweitzer was already exemplifying what it means to be a Volunteer. He served as radiation safety officer for the State of Tennessee during the Cold War. His work contributed heavily to the development of photoelectron scanning instruments, technology that made some modern medical scanning equipment possible. He was fond of the saying, “I have come to serve, not to be served.”

In 1960, Schweitzer was named the inaugural Macebearer, an award presented to a faculty member who has exhibited longstanding commitment to the university and the community. His love of investigation and the pursuit of knowledge led him to earn an MA in philosophy from Columbia University, followed by a PhD in philosophy from New York University. He was later awarded a ScD for his work in the history of science.

Schweitzer’s colleagues remember him fondly, often recalling his devotion to continued learning. Fellow professor and inorganic chemist Ben Xue met Schweitzer for the first time soon after joining the university in 1992.

“I was deeply impressed by his knowledge of the world, broad interests, and sharp mind,” said Xue. “George was a unique scientist and colleague, and I will miss him.”

During Professor Schweitzer’s time at the university, he served under 13 UT presidents and seven department heads. He saw the creation of the UT College of Veterinary Medicine, the UT College of Nursing, and the development of the UT System itself. He was with the department when it moved into the then newly built Buehler Hall, after spending years working with its namesake, Calvin Buehler. He published more than 150 academic papers and authored 17 books on chemistry and local and family history, including a history of the Department of Chemistry at UT. In 1970 he was named an Alumni Distinguished Professor.

A man in a suit pointing at equipment in a lab

Though he cited his research as his greatest pride point, Schweitzer’s teaching legacy cannot be ignored. Over the years he mentored more than 140 graduate students, ushering them toward PhD and MS degrees. He taught classes in the chemistry, philosophy, history, and nuclear engineering departments, and had the unique experience of teaching the grandchildren of students he had taught before.

“In my four years at the University of Tennessee, I have met with many of our alumni,” said Viktor Nemykin, current head of the Department of Chemistry. “Everyone remembered George and wanted to talk to him. His more than 75 years of service to the department and university are truly unmatched.”

When asked if he planned to retire, Schweitzer once responded that he had considered it at one time, but he had since recovered. He continued to teach into the current academic year and had planned to teach in the spring. With a career as expansive as Professor Schweitzer’s, it is impossible to recount every important contribution made to his discipline, the university, and beyond. At 99 years old, he experienced and contributed to the making of the world as it exists today, teaching and conducting research through most of it. The university and department are unlikely to see his legacy matched, and he will be sorely missed.

Gifts in honor of Dr. Schweitzer may be made here: giving.utk.edu/schweitzer

Share your memories of Dr. Schweitzer with us here.

Courtney Christopher headshot photo

Chemistry Researcher Studies Human Health at the Molecular Level

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Courtney Christopher started college as a pre-med major but realized chemistry could hold answers to complex human health questions. Now as a postdoctoral research fellow in the Department of Chemistry, she’s uncovering novel links between a microbial derived metabolite, the gut microbiome, and conditions ranging from systemic inflammation to Alzheimer’s disease.

Most of her postdoctoral work at the University of Tennessee, Knoxville, has stemmed from her discovery of 2,3-dihydroxypropane-1-sulfonate (DHPS) in humans.  

“Prior to my work, DHPS did not have a known role in human metabolism,” she explained. Her principal investigator is UT Chemistry Professor Shawn R. Campagna, who helped discover the role of DHPS in marine microbial communities a decade ago. 

“My contributions have been identifying DHPS in humans, discovering that this metabolite does impact human physiology, and providing data and generating hypotheses that will lay the foundation for future studies to uncover how DHPS may be a key regulator of human health and inflammation,” Christopher said.

She’ll be discussing all of her DHPS discoveries and summarizing the findings on DHPS in human health at the University of Tennessee Health Science Center’s Neuroscience Institute seminar series this October in Memphis.

This past summer she delivered oral presentations at the American Society for Mass Spectrometry and the American Chemical Society conferences, and her collaborator presented at the American Society for Microbiology conference. 

Vaping to Alzheimer’s

In one study, published in the journal metabolites, Christopher discovered a connection between DHPS and metabolic dysregulation, comparing DHPS levels in the stool of vaping and smoking subjects compared to controls. 

“This work provided the first evidence that DHPS, a microbial metabolite with an unknown role in human physiology, may be linked to vaping and smoking-induced metabolic dyshomeostasis and a basis for future research investigating the role of DHPS in human health,” she said. “I also identified correlations to cholesterol metabolism, acetylated amino acids, neurotransmitters, and vitamin B metabolism, which may provide insight into the physiological role of DHPS.”

In another, she discovered a previously unrecognized link between DHPS and neurodegenerative diseases (NDDs) such as Alzheimer’s, Parkinson’s, and amyotrophic lateral sclerosis (ALS). “The data suggest that cryptic sulfur metabolism via DHPS is a missing link in our current understanding of NDD onset and progression,” Christopher said.

Her hypothesis is that metabolic dyshomeostasis and increased flux through DHPS result in mitochondrial dysfunction and systemic inflammation in humans.

This academic year she is investigating the pathophysiological impact of DHPS dyshomeostasis on mitochondrial dysfunction. “Additionally, I plan to study how different intrinsic (biological sex, aging) and extrinsic factors (diet, diabetes, hypertension) are impacted by DHPS dyshomeostasis,” she said. 

Interdisciplinary Collaborations

Christopher was working on her bachelor’s degree in chemistry at Lincoln Memorial University when she first heard of the work in the Campagna Lab at UT using mass spectrometry-based metabolomics to investigate the etiology of Alzheimer’s disease. 

“I was so impressed with Dr. Campagna’s research on human health and his many interdisciplinary research collaborations with PIs (principal investigators) across the country.” She earned her PhD from UT in 2022.

“None of this work would have been possible without my mentor (Campagna) and incredible collaborators,” Christopher said, “Through the Biological and Small Molecule Mass Spectrometry Core (BSMMSC) in UT’s Department of Chemistry, I have had the opportunity to collaborate with brilliant scientists across the globe. They have given me scientific freedom to explore this new discovery and have provided invaluable support.”

Her collaborators include Assistant Professor Katie Morgan from the UT College of Nursing, as well as researchers from Augusta University, the Medical University of South Carolina, and Louisiana State University.

By Amy Beth Miller

Welcome New Faculty Members

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The Department of Chemistry is pleased to welcome to new faculty members in the 2024-2025 academic year. Their arrival brings us up to 26 faculty members. Their addition will expand our expertise and research capacity, providing even more opportunities for students to participate in cutting-edge research.

Joseph Clark – Assistant Professor

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Joseph Clark was born and raised in Rochester, NY. He attended St. John Fisher University, graduating with a B.S. in chemistry in 2008. In pursuit of his interest in organic chemistry method development and catalysis, he completed a Ph.D. in the research group of Professor Steven T. Diver at the University at Buffalo in 2014. He joined Professor M. Christina White’s group in September of 2014 at the University of Illinois Urbana-Champaign. While in the White group he received a NIH NRSA Ruth Kirschstein Postdoctoral Fellowship. Joseph joined the chemistry faculty at Marquette University in August of 2018 as an assistant professor and was promoted to Associate Professor in 2024. Beginning August 2024, Joseph accepted a faculty position in the Department of Chemistry at the University of Tennessee, Knoxville, and moved his group there. Joseph is a recipient of several major grants and awards such as the NIH ESI MIRA, NSF CAREER award, ACS PRF, and Thieme Chemistry Journals Award.

Ziying (Nancy) Lie – Assistant Professor

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Dr. Ziying (Nancy) Lei is an Assistant Professor in the Department of Chemistry at the University of Tennessee, where she leads research on atmospheric particles to advance our understanding of their significant impacts on climate change and air pollution. Her research focuses on the intricate properties of these particles, such as their size variability from 1 nm to 100 µm, varying acidity, diverse morphology, and complex chemical composition. These attributes are crucial as they continuously evolve through heterogeneous and multiphase chemistry, influencing both environmental health and climate systems.

Dr. Lei brings a commitment to excellence in research and education. She has contributed significantly to the academic community through publications in prestigious journals and conference presentations. Lei’s scholarship, recognized with several awards for her research achievements, is marked by a dedication to excellence and a passion for advancing the frontiers of her field.

As an educator, Dr. Lei is devoted to integrating real-world scientific challenges into the curriculum, fostering a learning environment that nurtures critical thinking and hands-on learning. She is committed to mentoring the next generation of scholars and professionals, using engaging teaching methods to inspire her students and providing mentorship that supports their academic and professional growth. Lei’s teaching philosophy emphasizes the development of skills necessary for success in a rapidly changing world, preparing students to understand and solve environmental challenges.

A woman standing in a chemistry lab

Graduate Student Earns Prestigious ACS Fellowship

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Miranda Limbach, graduate student in the Department of Chemistry, was chosen as one of four recipients of a 2024 American Chemical Society Analytical Graduate Research Fellowship.

A member of Assistant Professor Thanh Do’s research group, Limbach is currently finishing a summer internship with Merck. When she returns, Limbach will begin her fifth year of graduate studies at the university.

The goal of Limbach’s PhD research is to identify the underlying principles governing the membrane permeability of macrocyclic peptides. Macrocyclic peptides are being explored as a means of drug delivery that would target protein-protein interactions, potentially leading to new ways to treat a variety of diseases.

This prestigious fellowship awarded by the Analytical Division of the ACS is designed to support research, promote the growth of the discipline, and to recognize future leaders in analytical chemistry. The award will provide support to Limbach for 9 months, which will allow her to focus fully on her research without holding a GTA position.

Other winners of the nationally competitive award are from the University of Wisconsin-Madison, Florida State University, and the California Institute of Technology.

The American Chemical Society (ACS) was founded in 1876 and is one of the world’s largest scientific organizations. In addition to hosting regular conferences devoted to exploring new and continuing research across the discipline of chemistry, the ACS provides accreditation for undergraduate chemistry degrees, offers a variety of fellowships and awards for students and researchers, and publishes more than 80 peer-reviewed journals.

A young Asian man wearing a blue lab coat and clear safety glasses is using a glove box in a lab. A shadow of his image is reflected in the glove box window

Baccile’s Grant Prepares Community College Students for Four-Year Programs

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A young Asian man wearing a blue lab coat and clear safety glasses is using a glove box in a lab. A shadow of his image is reflected in the glove box window

Joshua Baccile, assistant professor in the Department of Chemistry, is leveraging a National Science Foundation (NSF) grant to provide summer research opportunities to community college students. He hopes the program will encourage more students to pursue a four-year degree.

The NSF requires all submissions to not only detail the proposed research, but to address the broader impacts of that research. NSF broader impacts are described as tangible societal benefits that go beyond the research’s contribution to the greater body of knowledge, and ensure that publicly funded research contributes to a public good.

Baccile addressed the broader impact question in his proposal by creating a summer research internship for community college students who are interested in pursuing a bachelor’s degree in chemistry or a closely related field. His goal was to tailor a comprehensive research program that would provide hands-on experience and professional development opportunities, and help ease the transition from community college to a four-year program.

“This program is important to me because I started out in community college. There is often a bit of a gap between the skills developed in a two-year program and the skills needed to succeed in a four-year program,” said Baccile. “When I was an undergraduate student, my summer research experience was critical to my continued pursuit of chemistry and I wanted to create an opportunity like that for our local community college students.”

To get the program running, Baccile had to first build a relationship with local community colleges and establish a pool of interested students. He reached out to Pellissippi State Community College (PSCC) via a colleague and visited the campus repeatedly to discuss the program with the college’s organic chemistry students. When the program began accepting applications, the response from students was overwhelmingly positive.  

“In the first year, we had a number of qualified applicants that we were forced to turn down because I simply didn’t have room for them in my lab,” said Baccile. “It was immediately clear this is an opportunity students want.”

Now in its second year, Baccile’s program has expanded beyond his own lab to include the research groups of Mike Best and Johnathan Brantley, fellow faculty members in the chemistry department. The addition of these labs has allowed the program to support more qualified students, a trend Baccile hopes to continue.

He notes that, thus far, all of the students who have participated in the summer internship program have gone on to four-year institutions in Tennessee, including UT’s chemistry department.

“This program is establishing pathways to four-year degree programs for Tennessee residents through research experiences. Not only is this helping individual students expand their future opportunities, it’s directly contributing to the state’s workforce development goals,” said Baccile.

Chemistry is a growing industry in the state of Tennessee. In the last six years, industry partners have made investments in excess of $400 million and created more than 2,000 jobs. Qualified and capable chemists will continue to be in-demand in Tennessee for the foreseeable future, and Baccile strongly believes that research experiences directly impact whether a student continues to work in the field of chemistry.

“My undergraduate summer research experience is the reason I’m a chemist,” said Baccile. “I think early exposure to research significantly improves the chances of students discovering their own passion for chemistry, and I am dedicated to extending the same invaluable opportunity I benefitted from to current and future community college students.”

The NSF proposal that funds Baccile’s summer research program has one year remaining. However, he hopes to find a way to continue and even expand the program into something more permanent in the future.

Dr. Baccile and graduate student Zack Hulsey stand with two young women in front of a case of lab supplies. They are wearing lab coats and safety glasses and are all smiling.
Dr. Baccile and graduate student Hima Davit stand with a young male student. They are smiling.
Dr. Baccile and graduate student Robert Maraski stand with a male student in front of a glove box. They are smiling.

New Graduate Student Fellowship Awarded

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Graduate student fellowships are financial gifts that provide support for graduate students and their research. These gifts can make it possible for students to give presentations at national conferences, purchase materials for lab work, and more. In 2024, the Department of Chemistry awarded a new graduate student endowed fellowship, thanks to the generosity of Robert and Phyllis Yokley.

Robert Yokley is an alumnus of the University of Tennessee Knoxville’s Department of Chemistry. Born in Hohenwald, Tennessee, Yokley began studying chemistry at Middle Tennessee State University. That study was interrupted by the Vietnam War, where he served a tour of duty as a U.S. Marine. When he returned home, Yokley returned to his studies and completed his B.S. degree. After working as a chemist for the Tennessee Department of Agriculture, Yokley decided to continue his education and joined the Department of Chemistry at UT, where he worked under Professor Gleb Mamantov.

After receiving his PhD, Yokley went on to work as a chemist in industry until his retirement in 2006. Yokley remains an active member of the American Chemical Society where he has served as the Chair of the Senior Chemists Committee.

The Dr. Robert A. and Phyllis F.J. Yokley Endowed Fellowship is the result of Yokley’s hard work over the years, and desire to support new generations of upcoming chemists. In keeping with Yokley’s experience, the fellowship gives preference to veterans, specifically members of the Marine Corps. The first recipient of the fellowship was graduate student and Marine Corps veteran Dakota Landrie.

A South Caroline native, Landrie joined the Marines right after high school, citing a desire to challenge himself. During his service, he deployed to Afghanistan twice with the 3rd Battalion, 7th Marine Regiment.

Landrie joined the chemistry graduate program in Fall 2022 and is now a member of Associate Professor Sharani Roy’s research group. His research uses theoretical models to explore electron transport. Currently in his third year, Landrie is working to become an interdisciplinary scientist, focusing on chemical physics.

“I am honored to receive this award and would like to thank Dr. Yokley for his service,” said Landrie.

The Dr. Robert A. and Phyllis F.J. Yokley Endowed Fellowship was awarded for the very first time at the department’s 2024 Honors Day, an event that celebrates the achievements of faculty, staff, and students. Robert and Phyllis Yokley were in attendance, along with their dog Otis.

Graduate Student Brings STEM Education to Knoxville Youth

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Candace Halbert, PhD candidate in the Department of Chemistry, was recognized by People Magazine last year for her work bringing STEM education to underserved Knoxville youth through her nonprofit organization Youth Outreach in STEM (YO-STEM). As a nontraditional student, Halbert is building the skills and knowledge that will allow her to serve her community and benefit the life and lives of children all over Knoxville.

After earning her master’s degree from Georgia Tech, Halbert pursued a career as a chemist and eventually began working as a scientific associate at the Spallation Neutron Source at Oak Ridge National Laboratory (ORNL). Halbert’s role at ORNL quickly expanded beyond managing a research instrument to include recruiting at conferences and career fairs.

As she continued working as a STEM professional, Halbert noticed that she was often the only woman or person of color in the room. She found herself wondering what could be done to change that. In 2016, after a number of high-profile killings on unarmed black men and the ongoing water crisis in Flint, Michigan, Halbert stopped wondering and started acting.

“Vine Middle School was collecting water for Flint so I went to donate, and I realized Vine was a STEAM school. I offered to volunteer and a few weeks later they contacted me and asked if I would be interested in starting a STEM program for girls,” said Halbert.

What began as a STEM club for girls, quickly expanded to a co-ed Build-a-Drone program, and in 2017, Halbert founded YO-STEM. YO-STEM is a nonprofit dedicated to providing underserved students with education and hands-on STEM experiences. Its three main programs are the original Girls in STEM program, STEM Saturday, and competitive co-ed Robotics. The first year YO-STEM’s robotics team competed, the made it all the way to the VEX Robotics World Championship.

“Our kids are amazing. All they need is the resources, time, and energy to be devoted to them,” said Halbert. “I always tell people we’re not saving these kids. We are giving them a tool and they’re learning to do everything they need with it. They’re strategizing, they’re practicing, they’re communicating. They’re doing the work; we’re just supplying the opportunity.”

Halbert’s journey to the Department of Chemistry at UT is intimately tied to her work with YO-STEM. Her experience as a working scientist in a national lab led Halbert to believe that a PhD would open new doors for her professionally, but she was hesitant to add graduate school to her existing priorities. As Halbert continued pouring energy into her nonprofit, YO-STEM expanded its services to more students and age brackets. It wasn’t long before one of her colleagues suggested she return to graduate school.

“I was speaking to my mentor and she pointed out how much more I could do for my community with a PhD. All this time friends and colleagues had said I should go back to school because it would help my career, and I knew they were right,” said Halbert. “But my mentor reminded me this degree could do so much more than just help my career, that it could really enable me to better serve my community and these students.”

After joining the PhD program at UT, Halbert quickly realized how different this graduate school experience would be. Some of this she attributed to her professional experience and personal growth, both natural and intentional. However, she also found the program’s focus on research and fostering rigorous scientific inquiry to be a much more effective approach for her as a student.

“This has been a completely different experience for me.  As part of an R-1 institution, the structure of the program here focuses on high-quality research and research proposals as measurements of success and ability,” said Halbert. “I think that’s a better way to prepare students for their future careers. The department is also very supportive. I can tell my committee wants me to succeed.”

Now in her third year, Halbert feels confident that she made the right choice to pursue a PhD at UT. She says that balancing her work as a graduate student, her work at ORNL, and her work with YO-STEM has been challenging but rewarding. In the last few years, she has welcomed other members of the chemistry program into the family of volunteers at YO-STEM, and is considering further expanding the organization’s offerings as students ask for additional programs. Halbert has even begun to see some of the earliest participants in her programs joining the Volunteer family as undergraduate students.

 One of my students is in computer science and another is in nursing. I love seeing them here at UT. It’s almost like we’ve come full circle,” said Halbert

As Halbert continues to progress through her PhD program, she is looking forward to leveraging the knowledge and skills she has gained at UT to the benefit of both her career and community. She has discovered her passion in STEM advocacy and says the Department of Chemistry has provided her with the invaluable education and experience she needs to become an even stronger advocate.

Learn more about YO-STEM here.