Design of a Portable and Affordable Biosensor Platform Device
Creators: Bai, Songtian
Publisher: name: University of Alberta Library
Year: 2023

<p>Metabolomics is a rapidly growing field that focuses on identifying and measuring <br>
the collection of chemicals present within a biological system. These chemicals, known as <br>
metabolites, play a crucial role in the functioning of the body and can provide valuable <br>
insights into various physiological processes. As a result, metabolomics studies have been <br>
utilized in a wide range of health monitoring applications, including screening for earlystage cancer. Traditionally, high-end analytical chemistry tools such as a <br>
spectrophotometer have been used to measure metabolites in biological samples through <br>
the application of colorimetry. These instruments, however, are typically expensive and <br>
require skilled technicians to operate. Due to these limitations, they are usually found in <br>
centralized labs and are not suitable for in-clinic or bedside use. Teaming up with <br>
researchers across the world, the research group I am a part of is attempting to address <br>
the issue of colorectal cancer screening in developing countries. Finally, we exceeded the <br>
requirements and developed a low-cost, hand-held, point-of-care optical sensor platform <br>
for general colorimetric-based metabolomic testing applications. This platform is <br>
equipped with a 3D printed light-tight case that contains light-emitting diodes (LED), <br>
sensors, microcontrollers, and a Bluetooth chip for wireless communications to an <br>
Android tablet. The performance of this sensor is evaluated using a colorimetric <br>
creatinine assay. Creatinine, a metabolite used to normalize urinary metabolite <br>
concentrations, was assayed using the Jaffe reaction, a commonly used method in <br>
laboratory settings. First, the color sensors were evaluated for stability using yellowcolored water that mimicked the Jaffe reaction color product. Next, the sensor was tested <br>
for accuracy using the Jaffe creatinine-picrate complex, which produced yellow-orange <br>
colored products. The sensor was able to detect creatinine concentrations ranging from <br>
3.80 mM to 50.28 mM, which is well within the physiological range expected in human <br>
urine. When compared to a spectrophotometer, which is considered the gold standard for <br>
this type of analysis, the sensor was found to be highly accurate. The sensor was able to <br>
accurately measure creatinine standards and high, medium, and low concentrations of <br>
spiked urine samples. One of the major advantages of this sensor is its cost-effectiveness <br>
and ease of use. Additionally, the sensor can be expanded to measure other metabolites <br>
via colorimetric assays, further increasing its versatility and utility in a wide range of <br>
applications. Furthermore, this thesis will address the developed workstation device on <br>
which the sensor can be mounted, and this device will serve as an assistant in the <br>
metabolite assay process by automating major steps that could be time-consuming or <br>
experience-dependent. Overall, this low-cost, hand-held, point-of-care optical sensor <br>
platform has the potential to revolutionize the field of metabolomics by providing a simple, <br>
cost-effective, and reliable method for measuring metabolites in biological samples. This <br>
can greatly benefit the medical field by providing a more accessible and efficient way of <br>
performing diagnostic tests, ultimately improving patient outcomes.</p>