John and Marcia Price College of Engineering
16 Developing Teaching Tools for Formaldehyde Electrochemical Sensors
Andrew Coda
Faculty Mentor: Kerry Kelly (Chemical Engineering, University of Utah)
Background
Formaldehyde (HCHO) is a volatile organic compound (VOC), and a common indoor air quality pollutant. Formaldehyde is a known carcinogen and The American Lung Association identifies the effects of short-term exposure to formaldehyde to include irritation of the nose/eyes/throat, difficulty breathing, and asthma attacks [1]. Similar to other air quality pollutants like PM2.5, formaldehyde can be measured with low-cost sensors, specifically an electrochemical sensor. These low-cost sensors provide an excellent opportunity for outreach modules and education materials.
Teaching Module
To model the working principle of an electrochemical sensor, glucose is used instead of any electrochemically reactive substance that is either costly or hazardous. With this outreach module, students construct two electrodes, one working (shown in Figure 1) and one reference. They can then measure the potential difference between the two when exposed to a spray of glucose solution [2]. With that measured potential difference students can construct a calibration curve. Ultimately, students will learn the engineering design cycle (Figure 2), while gaining knowledge and experience with sensors, circuits, and data analysis.
Figure 1. Example working electrode layers
Figure 2. Engineering design cycle as it pertains to this module
Future Work
In the future, the goal is to polish the existing outreach module and create a catalogue of education tools for all ages and multiple demographics, such as pamphlets recruiting adult sensor users.
References
[1] A. L. Association, “Formaldehyde,” American Lung Association, https://www.lung.org/clean- air/at-home/indoor-air- pollutants/formaldehyde#:~:text=Formaldehyde%20irritates%20the%20nose%2C%20eyes,attacks%2 0and%20other%20respiratory%20symptoms. (accessed Nov. 2, 2023).
[2] R. Cánovas, M. Parrilla, P. Blondeau, and F. J. Andrade, “A novel wireless paper-based potentiometric platform for monitoring glucose in blood,” Lab on a Chip, vol. 17, no. 14, pp. 2500– 2507, 2017, doi: https://doi.org/10.1039/c7lc00339k.
