Southwestern University Researchers Aim to Revolutionize At-Home Disease Detection

This summer, a group of researchers from Southwestern University's Physics and Engineering Department began a revolutionary project to develop a low-cost device for quick and reliable disease detection at the point of care, a venture that has the potential to transform global public health.

During the COVID-19 pandemic, millions of everyday Americans were introduced to at-home diagnostic testing. At the height of the pandemic from 2021 to 2022, more than 390 million COVID-19 at-home test kits were produced. It is estimated that roughly one-third of the U.S. population administered an at-home COVID-19 test at least once.

This new familiarity and comfort with home diagnostics created a lasting demand for tools capable of detecting disease quickly and reliably. Today, at-home kits to test for COVID-19, flu, RSV, pneumonia, and more are widely accessible and generally cost-effective.

Known as antigen tests, these kits can produce results in as little as 15 minutes and involve the collection of fluid from the nasal passage that is then mixed in a vial that breaks down cells and releases viral proteins. When this mixture is applied to a test strip containing specific antibodies, proteins bind, creating a visible line if the antigen is present.

Although convenient, these tests are often wildly inaccurate, with a 2025 Cochrane study determining that at-home antigen tests correctly identified COVID-19 infection in just 55% of people without symptoms. In many cases, those who self-administer antigen tests must still visit a physician to undergo a Polymerase Chain Reaction (PCR) diagnostic test.

"We are trying to cut that cost to $50. I wouldn't be working on it if I didn't believe that it was super innovative and could really impact the world." - Assistant Professor of Physics and Engineering August Kohls

PCR testing, which provides results at a 99.9% accuracy rate, involves the use of complex laboratory equipment to detect the presence of viral genetic material in a fluid or tissue sample. Although highly accurate, the equipment needed to administer PCR tests often costs upwards of $10,000, making it typically only available by professional healthcare providers.

At Southwestern, Assistant Professor of Physics and Engineering August Kohls, physics and computational mathematics double major Clay Elliott '27, and physics major and computer science minor Theo Phocas '26 are on a journey to build a device that combines the reliability and accuracy of PCR testing with the convenience and affordability of antigen testing.

"It is very innovative, mostly in terms of cost," Kohls said. "If you look up other people who are doing things like this, they have similar ideas, but they have cut the cost from $10,000 to $1,000. We are trying to cut that cost to $50. I wouldn't be working on it if I didn't believe that it was super innovative and could really impact the world."

The first phase of the project, which began this summer as part of the Southwestern Undergraduate Research with Faculty (SURF) program, involves the design and creation of a 3D printed device that allows for fluorescent disease detection, a process that uses incredibly fine readings of light, up to 10,000 times dimmer than ambient light, to spot disease-related molecules in cells.

"Theo is our 3D printing and CAD master. He has skills that I don't even have as an electrical engineer," Kohls said. "I explained the concept to him on a whiteboard and he sat down in Fusion, which is the CAD software, and had a rough model in about a minute. I said 'This is exactly what we need. You're a wizard. I'll be back in two hours.' And in two hours, he had a 3D printed prototype."

While at-home antigen tests are built around relatively simple chemical reactions involving proteins, the group's device requires more complex elements because it is based in DNA, the key to providing users with PCR-level accuracy. The bulk of the team's summer research involved designing, modifying, and perfecting the testing system itself, the first step in determining if Kohls, Elliott, and Phocas can achieve the goals that they set out to accomplish.

The group continues to actively test the device with simple positive controls. While early results are promising, Phocas, along with two additional engineering students, have continued the research into this fall to continue to refine the device.

"For me personally, I really like being on the cutting edge. That's where I find things that are exciting," Phocas said. "I don't want to be doing what's already been done. This research immediately puts us at that cutting edge."

Kohls estimates that there are at least two more phases of the project before the device resembles a fully formulated product that can be used in homes. The next step, set to continue after Phocas graduates in December 2026 and Elliott in May 2027, will likely center around sample clean-up. As nose swabs and saliva samples are often filled with contaminants, a process must be developed to clean up the sample prior to testing.

After that, Kohls is eyeing a collaboration with local healthcare providers that have access to live COVID, flu, and pneumonia samples that can be used for live disease testing.

"If it works, who knows, maybe you'll see me in five years with a company. If not, we'll go back to the drawing board," Kohls said. "That's how it goes."

"At a school like Southwestern, as an undergraduate, you're already at the top. You are given a lot of responsibility over the project. You get to really learn more about yourself, how you work, and how you work with other people." - Theo Phocas '26

The initial idea for a low-cost, high-accuracy disease detection device was sparked when Kohls was working on a similarly complex project in graduate school at Carnegie Mellon University. His graduate project involved producing complex solutions to solve a complex problem - solutions that were often impractical to reproduce and unlikely to make a lasting impact on society.

"When there are solutions that are not optimized, or are solved in a way that is way too complex, all I think to myself is 'you could have done it this way,'" he said. "With disease detection, I thought, 'there's a better and much simpler way to do this that is both cost-effective and much easier to manufacture.' I have been holding this project idea in my back pocket from when I was a graduate student and have kept approaching it from the lens of making it as easy and as cheap as possible."

Kohls continued to refine his ideas as he earned his M.S. and then Ph.D. in electrical engineering at Carnegie Mellon. It wasn't until he joined the faculty at Southwestern in July 2025 that he began to see a clear path forward for his research through the SURF program.

"After three years of thinking about solutions to this project, I kept finding more optimized routes until I landed on something that I wanted to test with," he said. "I refined the idea into something that was good for a SURF project, one that can be done in a reasonable amount of time, using the resources that I have at my disposal, and can be an opportunity to mentor students."

Held in labs and classrooms across campus, SURF provides SU faculty with the time, funding, and opportunity to pursue more in-depth research projects that often don't align with the time constraints of the academic year. Students are expected to treat their SURF research as a full-time job, complete with weekly paychecks and on-campus housing provided.

"The fact that I can work with a professor who's organized and fair, it actually feels like a dream job, way better than an internship," Phocas said. "At a school like Southwestern, as an undergraduate, you're already at the top. You are given a lot of responsibility over the project. You get to really learn more about yourself, how you work, and how you work with other people."

Each spring, students may submit applications to join summer SURF projects that align with their interests. Faculty then use a matching process to pair students with projects, ensuring the best possible outcomes for student success and faculty research objectives. Elliott and Phocas were chosen by Kohls for their expertise and knowledge.

"I have people like Theo and Clay and a lot of other engineering students who are truly top of any class," Kohls said. "I truly believe that. The students here are focused not just on the end goal, but on the journey to the destination, which makes them more productive, and often, the destination becomes better."

Students who participate in SURF receive the chance to conduct the types of research that are typically only available for graduate-level students at other institutions, something that Phocas experienced first hand after transferring to Southwestern from a large, out-of-state R1 university in January 2025. At his previous institution, research opportunities weren't readily available for undergraduate students.

"I'm an important piece, as an undergrad," Phocas said. "I don't have to fit into a box. I have my skills that I bring to the table, and I know the things that I need to learn, but I know that I can make an impact immediately by putting my spring on things. That has been the biggest positive."

Just weeks after transferring to Southwestern, Phocas was invited to sit in on a job interview that the University was conducting for a new physics professor. The interviewee that day was August Kohls.

"I thought it was so cool that Southwestern asked students to be part of a professor's interview," he said. "It was really fun, definitely an experience that I'll remember."

Kohls was hired shortly thereafter, and less than a year later, teamed up with Phocas and Elliott to begin their revolutionary research project.

"In his interview, he proposed this project and I was instantly interested in it," Phocas said. "For one, it involved something that needed to be built, and I already had quite a bit of experience in that. Second, there were elements that I haven't had experience with that interested me, mainly in biomedicine. It was pretty instantly that I knew I could come in and make an immediate impact and also branch out into other skills that I have been wanting to look into."

To learn more about the Southwestern Undergraduate Research with Faculty program, please visit southwestern.edu/undergraduate-research/surf.