Development of an Optical Sensor for the Methanol Detection in Exhaled Breath Based on the Arduino Hardware and Software Platform
Students Name: Sydir Bohdan Yaroslavovych
Qualification Level: magister
Speciality: Electronics
Institute: Institute of Telecommunications, Radioelectronics and Electronic Engineering
Mode of Study: full
Academic Year: 2022-2023 н.р.
Language of Defence: англійська
Abstract: The master’s thesis is devoted to the development of an optical sensor for the detection of methanol in the air exhaled by a person, based on the arduino hardware and software platform. Methanol is a dangerous poison [1]. It acts mainly on the nervous and cardiovascular systems, has a pronounced ability to cumulate. In humans, taking internally 5-10 ml of methanol or more can lead to severe poisoning, 30 ml can cause death. Getting into the body more than 80-150 ml of methanol (1-2 ml of pure methanol per kilogram of body) is usually fatal. The toxic effect of methanol develops within several hours, and effective antidotes can reduce the damage caused. Not only pure methanol is dangerous for life, but also liquids containing poison even in low concentration [2-4]. Consumption of only 6 ml of methanol can be fatal [5]. Therefore, a methanol detector for checking alcoholic beverages can help prevent outbreaks of methanol poisoning. The safety threshold for natural methanol in the liqueur (40 vol% ethanol) is 0.4 vol%, as such low levels are a by-product of fermentation. Thus, the detector must be able to distinguish between "safe" alcoholic beverages and adulterated ones with usually much higher methanol content. The paper provides data on existing gas analyzers used to determine the concentration of methanol in air, and formulates requirements for these sensors for use in medical purposes. A literature review was conducted, which considered the reasons for the presence of methanol in the human body, testing schemes, types of gas sensors, as well as an analysis of the characteristics of modern gas analyzers. Based on these data, a compact gas analyzer based on the Arduino Uno series controller was developed for use by private individuals or medical institutions specializing in the treatment of poisonings related to the human digestive system. An economic analysis of the feasibility of creating this gas analyzer was carried out. The principle of operation of the developed sensor is based on the fact that the vapor of some organic substances after absorption by the liquid crystal leads to a change in its spectral characteristics. This can be used as a basis for creating sensitive elements of optical sensors [6]. Study object - optical sensor for the methanol detection in exhaled breath based on the arduino hardware and software platform. Scope of research - optical properties of the sensitive element of the gas sensor based on the cholesteric-nematic liquid crystal mixture consisting of the E7 nematic liquid crystal and the active impurity CB15. Goal of research: development an optical sensor for the methanol detection in exhaled breath based on the arduino hardware and software platform. As a result of this master’s thesis, an optical gas sensor was developed to detect methanol in the air exhaled by a person. A cholesteric-nematic mixture of E7 liquid crystal and SV15 impurity was chosen as a sensitive element. This mixture has the property of changing its spectral characteristics under the action of methanol and ethanol. This feature was the basis of the developed sensor. Key words – cholesteric-nematic mixture, liquid crystals, optical sensor, methanol. References: Lin, L. et al. Low-temperature hydrogen production from water and methanol using Pt/?-MoC catalysts. Nature 544, 80–83 (2017). The American Academy of Clinical Toxicology Ad Hoc Committee on the Treatment Guidelines for Methanol Poisoning. et al. American Academy of Clinical Toxicology practice guidelines on the treatment of methanol poisoning. J. Toxicol. Clin. Toxicol. 40, 415–446 (2002). Kruse, J. A. Methanol poisoning. Intensive Care Med. 18, 391–397 (1992). Agence France-Presse. Voice of America News: death toll in Iran alcohol poisoning jumps to 84. https://www.voanews.com/a/death-toll-in-iran-alcohol-poisoning-jumps-to-84/4633468.html (2018). Bennett, I. L., Cary, F. H., Mitchell, G. L. & Cooper, M. N. Acute methyl alcohol poisoning: a review based on experiences in an outbreak of 323 cases. Medicine 32, 431–463 (2013). Chin-Kai Chang, Hui-Lung Kuo, Kea-Tiong Tang, Shih-Wen Chiu. Optical detection of organic vapors using cholesteric liquid crystals. Applied Physics Letters. 2011. Vol. 99, No. 7. P. 504–519.