Urinary tract infections (UTIs) cause major healthcare complications worldwide and are the most common of all bacterial infections. Traditional methods to diagnose UTIs either lack sensitivity or take too long. A new technology developed by scientists at Texas A&M University that uses fluorescence offers a different approach.
“To the best of our knowledge, this device is the first fully integrated, on-body, automated bacterial growth-monitoring platform for point-of-care UTI diagnostics,” explains Hatice Ceylan Koydemir, assistant professor and lead author of this research at Texas A&M University.
“With our wearable sensor, patients could detect a catheter infection before it becomes dangerous, and without requiring time-consuming lab tests,” she adds. “In addition, the device is easy to use, and measurements are performed non-invasively and without any sample handling, which minimizes the risk of infection for medical workers who are caring for the patient.”
Shining a fluorescent light on catheter-associated urinary tract infections
Catheters have been used since 3000 B.C., with the 1930s marking the development of modern balloon catheters. The minority of people with catheters develop UTIs but, because urinary catheters are the most common of all indwelling devices, the number of people affected is significant. Catheter-associated urinary tract infections are one of the most common hospital-acquired infections and, if left untreated, can lead to urosepsis. Furthermore, up to 80% of critical care patients have catheters fitted and any arising UTIs can lead to significant medical complications for already very sick people. In addition to severe medical complications, these infections represent a resource and financial burden, with each infection estimated to cost almost $3000 US.
Current UTI diagnostics are suboptimal. Urinalysis using dipsticks is a common, time and cost-effective test that lacks sensitivity. Conversely, urine culture is highly sensitive but takes time and delays treatment.
To tackle this perennial problem, researchers at Texas A&M University have leveraged advances in materials science and integrated these with wireless technology and a mobile phone application to develop a sensor that attaches to a catheter bag and measures fluorescence emitted by E. coli bacteria. This proof-of-concept design study focuses on detecting E. coli because it is one of the most common causes of UTIs and is responsible for more than 20% of catheter-associated urinary tract infections.
Describing how the sensor works, Koydemir notes, “Before use, we add a specially formulated compound to the catheter bag. If E. coli is present, the compound reacts with the bacteria and creates a fluorescent product. Our light sensor can measure that fluorescence and determine the level of E. coli present. Once the urinary catheter is placed on the body, real-time measurement begins through a custom-developed smartphone application on an Android phone.”
The future of smart catheters
To evaluate their device, the team performed laboratory experiments using saline samples as controls and urine samples spiked with E. coli. Initial findings show the device is sensitive and accurately detects E. coli infection. Further testing included other bacterial strains and confirmed the sensor is specific for detecting E. coli.
These promising results are just the start. The team will now validate the sensor against urine samples from patients with UTIs. Other plans include expanding the sensor’s ability to detect other bacteria species and making the device more portable by reducing multiple circuits into one. Pending further optimisation and confirmatory studies, the team hopes to gain approval from the Food and Drug Administration for patient use.
If approved, the sensor could be used across healthcare facilities, as Koydemir notes: “This cost-effective device could be widely distributed and used worldwide, as its fabrication is similar to making circuits.”
Her recent review published in Advanced Science discusses the development and application of such ‘smart catheters’ for medical diagnosis, monitoring and therapy, discussing how technology advances especially in sensors, robotics and communication are promising to revolutionise catheters in healthcare. These ‘smart catheters’ include vascular, intravenous and gastrointestinal applications that, in addition to the sensing function, offer therapeutic intervention.
Furthermore, the application of this novel sensor is not limited to catheter-associated urinary tract infection diagnostics. “The device can be used to detect general UTIs,” Koydemir explains, “because it can also be attached to a urine cup for real-time monitoring of bacterial growth.” Considering UTIs are the most common bacterial infection, the sensor could be a gamechanger for millions worldwide.
Koydemir’s work extends beyond urinary catheters and encompasses sensors, micro-fabrication technologies, transparent electrodes, mobile microscopes and wearable technology for point-of-care diagnostics. “Interdisciplinary research is essential for solving complex biomedical challenges,” Koydemir remarks. “By collaborating with leading experts across various fields, we aim to advance health care and develop innovative solutions for early disease detection at the point of care.”
References:
W. Xu et al., An integrated wearable fluorescence sensor for E. coli detection in catheter bags, Biosensors and Bioelectronics (2025), DOI: 10.1016/j.bios.2025.117539
P. R. V. S. Vallente and U. Rhea, Catheter-Associated Urinary Tract Infections (CAUTI), EBSCO (2023)
M. Althumayri et al., Recent Advances in Transparent Electrodes and Their Multimodal Sensing Applications, Advanced Science (2024), DOI: 10.1002/advs.202405099
A. Y. Tarman et al., Smart Catheters for Diagnosis, Monitoring, and Therapy, Advanced Healthcare Materials (2025), DOI: 10.1002/adhm.202503913
Featured Image Credit: Gerd Altmann via Pixabay
