Bioelectronic Innovations, Empowered by Chemistry

Bioelectronic Innovations, Empowered by Chemistry

UD Professor Laure Kayser received an NSF CAREER award to further her group’s materials science research

Whether it’s a smartwatch that can detect irregular heartbeats or a continuous glucose monitor, electronics that can interface with biology have already started to revolutionize the future of healthcare. But while the potential of these devices is far-reaching, the materials that make up future bioelectronics have to meet several different criteria — such as not causing damage or irritation to skin and avoiding toxic metals, for example.

Creating new organic, biocompatible materials that can interface with living systems is Laure Kayser, assistant professor in the Department of Materials Science and Engineering at the University of Delaware’s College of Engineering. Now, thanks to an award from the National Science Foundation (NSF), she and members of her lab will continue their fundamental research on a new class of polymers that could pave the way for future applications in human health.

The Kayser Lab specializes in designing, synthesizing and characterizing new plastics and polymers that can conduct electricity while safely interfacing with living systems. By working at the intersection of chemistry, polymer science and materials engineering, her lab is able to develop innovative design and synthesis approaches for creating new types of plastic materials.

Kayser, who holds a joint appointment in the Department of Chemistry and Biochemistry in the College of Arts and Sciences, said that what sets her group apart from others in the field of organic bioelectronics is a strong foundation in organic chemistry and their ability to make any material they want instead of only being limited to what’s currently available.

“We do modern chemistry, including chemistry that is not necessarily typically used in the field, and apply it to materials science,” said Kayser. “Because we have a background in chemistry and synthesis, we can make any material, characterize it, establish structure-property relationships and tailor it so the material can be interfaced with biology.”

Design rules for electronic highways and ionic waves

Starting in July, Kayser’s group will be investigating a new type of organic bioelectronic material. With a five-year, $654,206 Faculty Early Career Development Program (CAREER) award from NSF, her lab will study the fundamental properties of polymers that have properties inspired by living systems and also meet the criteria for being able to be incorporated into bioelectronic devices.

For this project, the lab will be studying derivatives of PEDOT:PSS. This polymer belongs to a class of materials known as organic mixed ionic electronic conductors, which have the unique ability to conduct both electrons and ions.

This is a necessary yet difficult to achieve property for bioelectronics: Typical electronic devices, such as laptops or cell phones, use electrons to transmit signals, while systems in biology, such as nerves, use ions. This difference in communication methods makes it difficult to “translate” signals from electronic devices into ones that a cell or organ can interpret.

Laure Kayser (right), an assistant professor in the College of Engineering’s Department of Materials Science and Engineering and doctoral candidate Vidhika Damani working in the lab with PEDOT:PSS, a polymer with the unique ability to conduct both electrons and ions.

Laure Kayser (right), an assistant professor in the College of Engineering’s Department of Materials Science and Engineering and doctoral candidate Vidhika Damani working in the lab with PEDOT:PSS, a polymer with the unique ability to conduct both electrons and ions.

There are also engineering challenges in creating this class of materials, Kayser explained. “There are very different design rules whether you want a material to be an electronic conductor or an ionic conductor,” she said. “For example, electronic conductors are very well ordered — like a highway for electrons to travel down. But if you want to make a good ionic conductor, ions usually like to be on a floppy, almost liquid environment, so more like a wave.”

Members of the Kayser lab, including doctoral students Chun-Yuan Lo, Vidhika Damani, Dan My Nguyen, and Elorm Awuyah, were instrumental in getting preliminary results for the proposed research. The team recently published a paper in Polymer Chemistry (which was also featured on the journal’s May 21st 2022 cover), where they determined the role of different chemical properties in PEDOT:PSS and how they could be changed to make the material more efficient in bioelectronic devices, a key finding that showcased how the group’s expertise in this field could be applied to PEDOT:PSS.

Through the CAREER award, the lab will continue studying derivatives of PEDOT:PSS to gain a solid, fundamental understanding of how to control both electronic and ionic conduction. The long-term goal is to develop design rules for fabricating bioelectronic devices with this class of materials in the future.

“Our lab’s focus is to understand deeply how chemical structures affect the electronic properties of those materials,” said Kayser. “Through this grant, we’re going to learn a lot about these materials — some of these ideas might fail, but we’ll learn something along the way.”

Materials science outreach and education

With this CAREER award, Kayser will also be leading different outreach and educational initiatives for both high school students and undergraduates.

Part of this work will include connecting with female students at local high schools. This will be done through both a materials science-focused outreach program as well as a mentorship program, where graduate students and senior undergraduate students will be paired with high school students to provide support throughout the college application process.

Researchers in Laure Kayser’s lab recently published a paper in Polymer Chemistry (featured on the May 21st 2022 cover) where they determined the role of different chemical properties in PEDOT:PSS and how they can be changed to make the material more efficient in bioelectronic devices.

Researchers in Laure Kayser’s lab recently published a paper in Polymer Chemistry (featured on the May 21st 2022 cover) where they determined the role of different chemical properties in PEDOT:PSS and how they can be changed to make the material more efficient in bioelectronic devices.

Kayser will also be working with Sheldon Hewlett, an assistant professor who leads instruction and teaching in the materials science and engineering department, on integrating research into undergraduate curriculum. With support from the CAREER award, junior year materials science students will conduct a polymerization of PEDOT:PSS, including synthesis, purification and characterization, as part of a laboratory module. There will also be opportunities for students to address additional research questions during the course module, as well as funded research programs for those who are interested in carrying their work into the summer.

Along with introducing students to the process of polymerization, Hewlett added that this project will allow students to work with a class of materials in a laboratory course that they are likely to encounter in their career. “Not only will this award give us an opportunity for students to do real research, but it also provides students with a novel material system to work with,” said Hewlett. “You don’t see a lot of lab courses working with these polymers at this level — of making a material from start to finish, and then characterizing it afterwards.”

Making new discoveries through ‘great fundamental science’

“Chemistry will be central to the discoveries that Laure Kayser’s research group will advance on plastics and other polymeric materials through this NSF CAREER award,” said Joel Rosenthal, professor and chair of the Department of Chemistry and Biochemistry. “Rather than simply tweaking or studying materials that already exist, the Kayser lab is adept at leveraging synthetic chemistry to discreetly control the composition, and by extension, the properties of new polymers for various applications, including bioelectronics. I’m incredibly excited to see how her group’s work will continue to develop over the next several years.”

Joshua Zide, professor and chair of the Department of Materials Science and Engineering, added, “Professor Kayser is a fantastic contributor to the Materials Science and Engineering Department, and we are lucky to have her. Her research translates the chemistry to myriad important applications, and the perspective she brings is a huge benefit to the whole department.”

While Kayser is excited about the potential of her research to potentially impact a wide range of applications and fields, she is also looking forward to the “great fundamental science” that this CAREER award will enable her group to do.

“It’s a relatively hot area that is going to continue growing, so it’s a good place for us to be leading the pack,” she said. “I’m hoping that by learning more about the fundamentals of these materials, it might inspire others to explore different molecular designs and how they can be translated into devices. Overall, I think we’re going to make lots of really cool discoveries.”

| Photos by Evan Krape |

Fullbright Award Winners

Fullbright Award Winners

UD students continue to be honored by premier international scholarship programs

Three University of Delaware students — current and recently graduated — have been named recipients of 2022 U.S. Department of State Fulbright scholarships. The Fulbright Program is the nation’s premier international scholarship program, designed to foster mutual understanding between United States citizens and people of other countries. An additional recent UD graduate was the recipient of a Critical Language Scholarship, which provides an opportunity for students to learn languages essential to national security.

The Fulbright U.S. Student Program awards allow young graduates and graduate students the opportunity to conduct research, study or teach English in more than 140 countries.

Jana Mae Huss

Jana Mae Huss

Jana Mae Huss, who graduated in 2022, earned an English Teaching Assistant Award to Germany. Prashant Ramesh, a doctoral student, earned a Research Fulbright to study in France. Elaine Ansah, a 2021 graduate, earned an English Teaching Assistant Award to study in Kenya.

Huss completed their bachelor’s degree in elementary education with a concentration in English as a second language this past spring. During their time as a UD World Scholar, they studied in Madrid, Spain. Before coming to UD, Huss took German classes and studied in Germany, hence why they were interested in returning to the country. Huss plans to pursue a career in English as second language (ESL) and is currently in Hamburg, Germany, working in a K-12 classroom for their Fulbright English Teaching Assistantship.

Prashant Ramesh (pictured above) was excited to win the Fulbright-Universite Paris-Saclay Doctoral Research Award, which is only granted to three U.S. students each year. Ramesh is pursuing his doctoral degree in materials science and engineering at UD, and was looking for opportunities that involved academic collaborations abroad. He will be conducting doctoral research on quantum optics of solid state quantum dot molecules. He said he looks forward to expanding on his almost-forgotten high school French language skills. He said his research and international experience in India and Thailand while working in industry made him a strong candidate for the award.

Elaine Ansah (not pictured) earned her bachelor’s degree in political science with a concentration in global politics and a minor in Africana studies in 2021. While at UD, she was president of the Delaware African Student Association and senator for the Student Government Association. She is currently in Kenya working via her Fulbright English Teaching Assistantship.

Kiara Cronin

Kiara Cronin

Kiara Cronin was selected as a Critical Language Scholarship (CLS) recipient to learn Swahili. The Critical Language Scholarship (CLS) Program is an intensive overseas language and cultural immersion group-based program for American students enrolled at U.S. colleges and universities. Students spend eight to 10 weeks abroad studying one of 14 critical languages. The program includes intensive language instruction and structured cultural enrichment experiences designed to promote rapid language gains.

Cronin, normally, would have joined the program in Tanzania, but the pandemic prompted a change to virtual instruction. Cronin graduated in 2022 with an Honors bachelor of arts degree in history and international relations with a concentration in diplomacy. She said she hopes to work for the U.S. Department of State or a similar non-governmental organization, making use of her new language skills. While at UD, she was a Eugene du Pont Memorial Scholar and interned with the International Center for Religion and Diplomacy, a non-profit organization focusing on peace building in conflict zones.

Learn more about Fulbrights at UD

Interested students and alumni are encouraged to contact UD Fulbright U.S. Student Program and Critical Language Scholarship advisors in the Honors College at honors@udel.edu.

| Photos courtesy of U.S. State Department, Prashant Ramesh, Jana Mae Huss, Kiara Cronin |

The TuFF Age

The TuFF Age

UD researchers tackle new task in making complex material more viable for building aircraft

TuFF — Tailored Universal Feedstock for Forming — is a strong, highly aligned, short-fiber composite material that can be made from many fiber and resin combinations. Created at the University of Delaware’s Center for Composite Materials (CCM), it can be stamped into complex shapes, just like sheet metal, and features high-performance and stretchability up to 40%.

Since its introduction, CCM researchers have explored applications for TuFF, from materials for repairing our nation’s pipelines to uses in flying taxis of the future.

Now, armed with $13.5 million in funding from the U.S. Air Force, UD mechanical engineers and co-principal investigators Suresh Advani and Erik Thostenson along with industry collaborators Composites Automation and Maher and Associates are working on ways to improve manufacturing methods for TuFF.

“I am really excited at the opportunity to mature the TuFF pre-pregging process and demonstrate high-throughput composite thermoforming for Air Force relevant components,” said David Simone of the U.S. Air Force.

The goal is to enable lighter-weight composites to become cost-competitive with aluminum for creating small parts found in air vehicles.

Advani explained that when it comes to making aircraft materials more cost-efficient, reducing a material’s weight even a mere kilogram, just 2.2. pounds, will reduce fuel consumption and emissions and can result in thousands of dollars in savings over time.

This is because aircraft are heavy. A Boeing 747, for example, weighs a whopping 404,600 pounds. A B2 Stealth Bomber in the U.S. Air Force, meanwhile, tips the scale at over 43,000 pounds.

“In general, the aerospace industry wants to reduce weight and replace metals,” said Advani, George W. Laird Professor of Mechanical Engineering. TuFF is a good option because the material can achieve properties equivalent to the best continuous fiber composites used in aerospace applications.

Advancing TuFF thermosets

Until now, most of the work around TuFF has focused on thermoplastic composite materials that melt when heated, becoming soft and pliable, which is useful for forming. By contrast, TuFF thermosets have a higher temperature threshold, making them useful for aerospace applications. But TuFF thermosets have manufacturing challenges, too, including the long manufacturing times necessary to make a part.

In this new project, Thostenson and Advani will work on ways to improve the viability of thermoset TuFF composites. To start, the researchers will characterize the starting materials’ mechanical properties to understand how to make TuFF thermosets reliably and consistently. The research team will explore whether they can make the material in a new way, using thin resin films and liquid resins. They will test the limits of how the material forms and behaves under pressure and temperature, too.

“How does it stretch during forming in a mold? What shapes can we make? When does it tear or thin or develop voids that can compromise material integrity?” said Advani.

Having a database for such properties and behaviors will be useful in understanding TuFF material capabilities and limits, and to inform efforts to model and design parts with TuFF.

Thostenson, professor of mechanical engineering, is an expert in structural health monitoring of materials. He will advance ways to embed sensor technology into TuFF thermosets. This would allow the researchers to see from the inside how the material is forming and curing during its manufacture, in hopes of being able to gauge—and improve— the material’s damage tolerance.

It’s intricate work. To give you an idea of scale, a single layer of TuFF material is approximately 100 microns thick, about the diameter of the average human hair. The carbon-nanotube sensors Thostenson plans to integrate into the material are smaller still—one billionth the width of a human hair.

“This would allow us to do health monitoring for the materials and parts during service life, but you could also imagine using sensor technology to detect a defect during manufacturing,” said Thostenson.

While it remains to be seen whether this is possible, Thostenson said having this ability could result in real cost savings for manufacturing methods, where real-time knowledge of how a material is curing could help the researchers speed up production. Additionally, if there is a material failure, such as a tear, the sensors could point the researchers where to look in the process.

The research team also plans to develop a virtual modeling system to refine the material-forming process through computer simulation instead of by trial and error. In this way, the team will better understand each step in the material-forming process, enhancing the team’s ability to make TuFF materials consistently and reliably — a must for aerospace applications.

“I am hoping this work will allow us finally to make composites cost competitive with the metal industry,” said Advani.

In addition to Thostenson and Advani, the team includes, from CCM, Jack Gillespie, Dirk Heider, Shridhar Yarlagadda, Thomas Cender, John Tierney and Pavel Simacek, along with four to five graduate students.

UD’s LaShanda Korley Appointed U.S. Science Envoy

UD’s LaShanda Korley Appointed U.S. Science Envoy

Esteemed engineer to travel the world to advance science and technology cooperation with U.S.

LaShanda Korley, Distinguished Professor of Materials Science and Engineering and Chemical and Biomolecular Engineering at the University of Delaware, has been appointed a U.S. Science Envoy for 2023. The announcement was made by the U.S. Department of State on Tuesday, Dec. 6.

Through the Science Envoy Program, eminent U.S. scientists and engineers leverage their expertise and networks to forge connections and identify opportunities for sustained international cooperation, championing innovation and demonstrating America’s scientific leadership and technical ingenuity.

Korley is among seven distinguished scientists who will begin service as U.S. Science Envoys in January 2023. Like their 23 predecessors, these esteemed scientists are approved by the Secretary of State and will engage internationally at the citizen and government levels to enhance relationships between other nations and the United States, develop partnerships and improve collaboration.

According to the U.S. Department of State, Science Envoys leverage their international leadership, influence and expertise in priority countries and regions to advance solutions to shared challenges. They travel as private citizens and help inform the State Department, other U.S. government agencies and the scientific community about opportunities for science and technology cooperation.

Korley is a global leader in applying biologically inspired principles and approaches to the sustainable use of polymer-based materials, including plastics. She is the director of the Center for Plastics Innovation, an Energy Frontier Research Center funded by the U.S. Department of Energy that is working to chemically transform plastic waste — a pollution problem plaguing the world — into fuels, lubricants and other valuable products.

She also leads Bio-Inspired Materials and Systems, a global project funded through the National Science Foundation’s Partnerships for International Research and Education, which aims to develop programmable materials for soft robotic systems, and she is co-director of the UD Center for Hybrid, Active, and Responsive Materials, an NSF Materials Research and Science Center that is driving materials innovation in fields ranging from biomedicine to cybersecurity.

The recipient of numerous awards and honors, Korley is a fellow of the American Physical Society, the American Chemical Society Division of Polymeric Materials: Science and Engineering, and the American Institute for Medical and Biological Engineering. She received her bachelor’s degrees from Clark Atlanta University and the Georgia Institute of Technology and her doctorate from the Massachusetts Institute of Technology. She completed postdoctoral studies at both MIT and Cornell.

Joining Korley in the 2023 cohort of U.S. Science Envoys are Drew Harvell (Cornell University), Jessica Gephart (American University), Christine Kreuder Johnson (University of California, Davis), Prineha Narang (UCLA), Frances Seymour ( World Resources Institute) and Kyle Whyte (University of Michigan). The State Department announcement has more information about the other envoys.

 Photo illustration by Jeffrey C. Chase  

A Pioneer in Polymer Physics

A Pioneer in Polymer Physics

UD Engineering’s LaShanda Korley elected as a 2022 American Physical Society Fellow

University of Delaware College of Engineering Distinguished Professor LaShanda Korley has been elected as a 2022 Fellow of the American Physical Society (APS) “for innovative bio-inspired strategies to control architecture, assembly, and mechanics of soft material systems.”

Korley, who holds appointments in the departments of Materials Science and Engineering and Chemical and Biomolecular Engineering, and her research group take inspiration from nature to design new polymers using innovative molecular-level design strategies and manufacturing approaches. Korley is also the director of UD’s Center for Plastics Innovation (CPI) and the co-director of the Center for Hybrid, Active, and Responsive Materials (CHARM).

By studying the architectures and design rules used by the natural world, Korley’s research helps materials scientists bridge the gap between fabricating simple, sustainable materials that also have a wide array of complex functions and downstream applications.

“Our group has a strategic vision on the interconnection between molecular design, engineering and materials science to design functional polymers,” Korley said about what makes her group unique. “We tackle the full macromolecular design spectrum from chemistry to processing to impact polymer architecture and function.”

Among her group’s long-standing research projects is their innovative work on spider silk, a biological material that Korley says continues to be a rich source of inspiration due to its unique and tunable mechanical behavior. Her group is also exploring the possibilities of using lignin, an organic polymer that is a component of tree bark, as a building block for plastics in lieu of petroleum-based products, as well as connecting polymeric features to new deconstruction and upgrading strategies for plastics waste.

“Professor Korley has made substantial contributions to understanding the polymer physics of network-forming systems through an exquisite mix of detailed polymer synthesis, materials characterization, and polymer processing,” said Thomas Epps, III, the Allan and Myra Ferguson Distinguished Professor of Chemical and Biomolecular Engineering, who nominated Korley for this award. “Her activities bring actionable insights that promote new applications of polymeric materials.”

Each year, APS, a scholarly society and publisher for the physics community, recognizes less than 1% of its members through the APS Fellowship Program. Korley’s outstanding contributions in bio-inspired materials science research was recognized by the Division of Polymer Physics, and she will receive her certificate at the APS annual meeting in March 2023.

“As a chemical engineer who works on polymer science and engineering, fundamental physical principles are what’s driving the design, so physics and engineering go hand in hand,” Korley said of being recognized by the APS. “If I’m designing a material at the molecular level, I have to understand and apply these underlying polymeric physics concepts.”

Along with her election as an APS Fellow, Korley is also a 2022 ACS Division of Polymer Materials Science and Engineering (PMSE) Fellow, a recipient of the 2021 AIChE Minority Affairs Committee (MAC) Gerry Lessells Award, was named a 2020 American Institute for Medical and Biological Engineering (AIMBE) Fellow, and received the 2019 National Organization for the Professional Advancement of Black Chemists and Chemical Engineers (NOBCChE) Lloyd N. Ferguson Young Scientist Award.

“I am extremely pleased to see Professor Korley receive this well-deserved recognition, joining other Fellows within the department,” said Joshua Zide, professor and chair of the Department of Materials Science and Engineering. “Her work serves as an inspiration to her colleagues, and we are always happy to see others also recognize her impact in the world. Locally, we appreciate that she is also an outstanding citizen of the department, and the students appreciate her teaching and mentorship.”

Referring to what the future holds for her group, Korley said, “There’s still more molecular engineering to do, and lots of questions driven by trying to understand concepts from nature that we see around us and that inspires us. Overall, I feel honored by this recognition from APS — not just for myself, but for my students, because they are the ones that believe in our lab’s large-scale vision and drive the innovation that makes this work possible.”

Article by Erica K. Brockmeier | Photo by Kathy F. Atkinson | October 19, 2022