Honors Theses

Date of Award

Spring 5-7-2022

Document Type

Undergraduate Thesis


Biomedical Engineering

First Advisor

Troy Drewry

Second Advisor

Glenn Walker

Third Advisor

Thomas Werfel

Relational Format



Hyperammonemia is a life-threatening metabolic condition that is characterized by elevated levels of ammonia concentrations in the blood. Resulting from serious conditions such as chronic kidney disease or liver failure, the limited functions of the liver and kidney lead to an increase in blood urea nitrogen (BUN) within the body. Currently, there are a wide variety of treatments for this condition, ranging from various medications to surgical procedures such as liver transplants. However, there is a lack of variety in diagnostic testing methods to determine a patient’s ammonia levels. In most cases, patients will need to schedule a doctor’s appointment to perform a blood test; blood samples are sent to a lab to then be analyzed for ammonia concentrations. Though this method is sufficient, it is often extremely complicated, costly, and time-consuming. Moreover, patients with hemophobia or sensitivity to being pricked often find this testing procedure extremely uncomfortable. Thus, our biomedical engineering senior design team sought to develop a non-invasive screening device that detects ammonia in real-time. There is a reasonable correlation between blood urea concentration and mouth-exhaled ammonia concentration. The device contains an ammonia sensor that allows for the detection and display of ammonia levels through mouth exhalation. This sensor, when in the presence of ammonia, rises in conductivity along with the rising gas concentration. With the device, a detailed instruction pamphlet will be included which will provide safe operating instructions for the user. The device is currently in development as proof of concept. With sufficient funding, resources, and research the potential for more accurate detection sensors is viable.

Creative Commons License

Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.



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