Date of Award
Master of Science (MS)
Dr. Robert A. Latour, Committee Chair
Dr. George Chumanov
Dr. Delphine Dean
There is a great need for an at-home, simple, inexpensive, and noninvasive testing method to monitor the blood phenylalanine (Phe) levels of patients with PKU. PKU is a rare genetic disorder that affects approximately one out 15,000 people, which results in dangerously high levels of Phe in the blood. This project aims to show proof of concept for such a test, which is based upon a previously developed test method that was historically used to diagnose PKU from a urine sample. This redesigned test method represents the optimization of a little-understood reaction between Fe3+ ions and phenylpyruvic acid (PPA) that results in a color change. PPA is a metabolic byproduct of elevated blood Phe levels, thus enabling it to be used as an indicator of this genetic disease. The improved test increases sensitivity to the presence of PPA by two orders of magnitude over the previous method by including custom test substrates, controlled lighting conditions, and smart phone technology. The process by which the test substrates were developed is presented, as well as their performance for the quantification of PPA concentration in a urine sample. The additional accuracy of the refined method is primarily provided by the implementation of a custom-made device to control light conditions combined with the measurement of color using a smart phone to photograph test samples combined with an RGB color application for color quantification. The final test proposed is inexpensive, safe, and simple enough for a lay person to do at home. Further optimization and calibration to individuals with PKU will be needed for the test to be commercially viable.
Cholewczynski, Alexandra, "Proof of Concept for a Urine-Based Method for Monitoring Blood Phenylalanine for Patients with PKU" (2016). All Theses. 2481.