Applications range from air quality analysis to patient health care – ScienceDailyDa
As gases emitted from certain solids or liquids, volatile organic compounds (VOCs) comprise a wide variety of chemicals. Many of these chemicals have been linked to a range of harmful human health effects, from eye, nose and throat irritation to liver, kidney and central nervous system damage.
The ability to easily, quickly and reliably detect VOCs in air samples is valuable for various practical applications, from determining indoor air quality to screening patients for diseases.
in the Review of scientific instruments, from AIP Publishing, researchers at the Technical University of Gdansk in Poland describe a measuring device for analyzing air samples with various VOCs.
The setup “uses commercial and prototypical resistive gas sensors with low energy consumption to detect volatile organic compounds such as methane, ethanol, toluene, methylene, nitrogen dioxide, formaldehyde, ammonia, among other things, in air samples,” said researcher Andrzej Kwiatkowski. “The sensors change their resistance in the presence of VOCs, which are present in the environment and the exhaled air.”
After the environmental conditions such as humidity, temperature and air pressure have been monitored, the device inhales a sample of air, either from the atmosphere or from a breath sample, so that the sensors in its 220-milliliter aluminum gas chamber can analyze VOCs and react to them in real situations.
The device consists of the gas chamber, a set of electric valves and an electric micropump and is controlled by an electronic touchscreen module that can process and store data. Sensor responses are recorded and can be parameterized with various detection algorithms for further data processing.
In practical applications, the instrument can detect and measure the presence of VOCs within 10 minutes.
“The setup is a cost-effective device with simplified maintenance and service,” said Janusz Smulko, one of the co-authors. “Additional environmental sensors increase the accuracy of the gas measurement by correcting effects caused by changes in temperature and humidity. The device can monitor the air quality that is collected in a human environment, such as an office or warehouse, to detect mold or bacteria from emitted odors.
“In medical applications, physicians can use this non-invasive method to examine patient exhalation to signal the need for closer examination.”
Researchers are currently using it in hospital studies to determine the difference in exhaled air between healthy volunteers and patients infected with the COVID-19 virus.
Source of the story: