Optical uric acid detection system in the ultraviolet (uv) region for gout diagnosis application /
Nor Mazlee Norazmi
- xviii, 177 pages : illustrations (some color) ; 30 cm. + 1 CD ROM
Faculty of Electrical & Electronics Engineering
Thesis (Doctor of Philosophy) -- Universiti Malaysia Pahang – 2021
Includes bibliographical references
This thesis describes an optical fibre sensor for the detection of uric acid (U.A) molecules and measurement of its concentration in the Ultraviolet (UV) wavelength region. Based on the medical studies, the concentration of uric acid which exceeds the normal rate ( > 7mg/dL for men and > 6mg/dL for women) in the human body can lead to Hyperuricemia and form numerous crystallites in the human joints. This disease is called Gout which is a common disease nowadays. It may cause swelling, intense pain and joint inflammation to the patient especially during intense activities. Various methods are carried out to measure uric acid concentration in the human body. Current practices have drawbacks that consume a lot of time to give results. Certain techniques are based on the consumption of another element for measuring the uric acid concentration in the sample. In certain experiments, a uric acid sample is mixed with a particular substance which can give effects on the properties and concentration of uric acid. In this research, an open-path optical sensor was developed to identify the optimal wavelength of uric acid molecule and measure its concentration in the UV region with a fast detection time, 3s. The developed optical sensor was also tested through the openpath technique to measure a few set of uric acid concentrations. The uric acid sample were prepared with different concentrations; 0.2mg/ml, 0.4mg/ml, 0.6mg/ml, 0.8mg/ml and 1.0mg/ml. The working principle is based on spectroscopy study. The absorption cross-section was calculated using Beer’s Lambert Law formula to indicate the absorption curve peak of the uric acid molecule due to its molecular structure. Spectrometer calibration was done using the Mercury HG-1 lamp to ensure that the optical sensor gives results with less errors. The experimental setup consists of a deuterium light source, spectrometer, cuvette holder, cuvette, optical fibre cables and computer to display results. The firmware of the sensor was developed using LabVIEW to make the sensor work in real-time. Spectrasuite does not have this advantage since the data has to be manually collected for analysis. In the experiment, the optical sensor was successfully optimized. The noise reduction was done using the average method. The sensor is able to measure the uric acid concentration of the five samples at the particular UV absorption curve peak, 294.46nm with a low noise signal. The cross-sensitivity issue occurs between uric acid and urea since both of these molecule absorb UV light at the same wavelength. The absorption curve line of urea was successfully deducted using the ratio technique. Thus, the optical sensor is able to only measure uric acid concentration. The absorption of carbon dioxide and oxygen can be ignored due to very low absorption in the UV region. This is a good potential that the optical sensor can identify the optimum wavelength of a uric acid molecule and measure the concentration in a short time. It is 60 times faster than the existing technique.
THE0009341(Local)
Faculty of Electrical & Electronics Engineering Technology--Dissertations