Capstone teams use light to make hospitals healthier for patients and providers
Startup company LumiVici sponsors Team 25055 in developing a self-sterilizing urinary catheter, plus Team 25012’s exploration of protective gear for health workers.
(From left) Gabi Andreakis, Ella Marshall, Dennis Shaw, Kyle McIllece and Omar Ramos test the LumiVici self-sterilizing catheter at the University of Arizona Water and Energy Sustainable Technology Center.
The co-founders of LumiVici, a biomedical startup company, strive to lower hospital-acquired infections by developing a catheter prototype that kills bacteria without chemicals. Sharon Keene and Neal Brock also hope to offer a face shield product that protects health care workers and reduces medical waste.
LumiVici became a first-time Interdisciplinary Capstone program sponsor this year, tasking two teams with sanitizing medical tools with light.
Team 25055 presented a system that uses antimicrobial light to sterilize infection-prone areas on catheters at the 2025 Craig M. Berge Design Day.
Catheter-associated urinary tract infections (CAUTIs) are one of the top five hospital-acquired infections in the United States. These infections occur when germs enter the human body – either from the tip of the catheter, the connector between the catheter and a drainage bag, or the opening of the urethra. With multiple entry points available for germs, CAUTIs are common; 75% of UTIs developed in the hospital are caused by catheters.
Keene and Brock set out to address the high rates of catheter-associated UTIs with the help of capstone students, tasking them with identifying creative applications for antimicrobial light wavelengths in all the high-risk entry points.
“Part of my motivation for joining this project is because it's a startup company, so we have a lot of freedom in what we can do in our design,” said Ella Marshall, team lead and biomedical engineering graduating senior.
Reimagining hospital equipment
Keene, who trained in general surgery and graduated from the University of Arizona surgical residency program, remarked that efforts to prevent infections in catheters and drains haven’t changed much since her training days.
“Drains are a two-way conduit and can become a source of infection,” she said. “Antibiotics can be delivered to surrounding tissue via the bloodstream but cannot be delivered to a drain which has no blood supply. We want to provide a method that maintains disinfection of drains and catheters.”
Keene and Brock found that certain light wavelengths can kill bacteria and fungi.
UVC wavelengths (200-230 nanometers) are identified as safe for human exposure, but the catheter team determined there was limited research on its safety for human tissue and decided to use the wavelength of 405 nanometers.
“This is a fairly new idea,” said Marshall. "The finding that far UVC wavelengths are safe for human exposure has only been recognized for around five years, but 405 nanometer light has been studied for its antimicrobial effect for a couple of decades.”
The team’s system used an optical fiber to create a tube of mirrors that bounces the light down the catheter, directing it to the patient.
“We've designed the fiber in such a way that when it gets to the end and toward the patient, it releases all of the 405 light that was produced by the LED in a specific radiance pattern that helps uniformly kill the bacteria,” said Dennis Shaw, project procurement lead and optical sciences and engineering senior.
Charles Gerba (far left), Sharon Keene (center) and Neal Brock (far right) provide opportunities to study the project in a professional lab environment.
Next, the team researched the efficacy of its bacteria-killing abilities with an E. coli study at the Water and Energy Sustainable Technology Center (WEST). Charles Gerba, professor of public health and microbiology in the Department of Environmental Science, allowed the students to use his lab as well as guidance from associate research professor Kelly Bright to design and conduct their studies.
The students evaluated their catheter against a control catheter. Both were infected with E. coli – a bacterium typically associated with urinary tract infections – to demonstrate the strength of the self-sterilizing light. Results showed a 99% reduction in bacteria.
LumiVici has filed a patent for a clip-on device to apply germicidal wavelengths, which incorporates the students’ work on this project. Keene said their work will be instrumental in future iterations.
Capstone: A safe space for startups
LumiVici also sponsored Team 25012, using similar germicidal light technology but a different wavelength. The team reviewed the evidence for safety and efficacy of Far UVC 222 nanometer wavelengths to develop a self-sterilizing face shield for health care workers.
This patented technology was inspired by the coronavirus pandemic when personal protection equipment was in short supply and nonreusable. The reusable face shield creates a substantial barrier between germs and a health care worker’s face, using 90-second cycles of light treatment.
Team 25012's face shield uses 222-nanometer wavelengths from an excimer bulb to protect health care workers with continuous bacteria sterilization.
At WEST, the team tested the design by shining light on its surface. They sprayed it with virus particles, then swabbed it before and after a 90-second cleaning cycle to see how well the light disinfected the face shield exterior.
“We were able to see the effectiveness of our light source to deactivate the test virus and then relate that to other diseases like COVID and influenza,” said team lead and BME senior Caitlin Ruhland. “We found we had a 90% disinfection efficiency.”
Keene and Brock want both devices to be financially accessible to health care workers and the public. But for a startup company like LumiVici, research and development can increase investment costs, which trickle down to the consumer.
Brock said he knew working with the capstone program would enable LumiVici to reduce development costs while also capitalizing on the skills of College of Engineering students.
“Having some physical hardware and data showing that a device concept works is pretty convincing, and it makes it a lot easier to raise money from investors,” he said.
“The capstone program is where you get these multidisciplinary teams, these young creative minds that think differently, and it's relatively inexpensive.”