This gas sensor, made using 3D-printed conductive ink, could help diagnose methanol poisoning quickly and easily. Credit: Kamrul Hassan
Researchers have developed a new electrically conductive ink that can be 3D printed onto ceramic to create a novel sensor which rapidly detects small concentrations of methanol in breath. The research represents a significant step forward towards developing a “methanol breathalyzer” which can be used to efficiently diagnose methanol poisoning.
Despite their structural similarities, methanol and ethanol have significantly different effects on the body once ingested. While ethanol can cause nausea, dizziness, and impairment, small amounts of methanol can lead to blindness and even be fatal in some cases. Due to its low cost, methanol is a common adulterant in alcoholic beverages, a practice which dates to a time when bootleg operations were more common. Even today though, this practice still leads to methanol poisoning and fatalities.
Current methanol testing methods require analysis of blood samples, a process which is costly and made even more difficult by the fact that tainted alcohol is most commonly found in low-income countries.
To provide a better testing alternative, the researchers developed a new conductive ink by combining a zirconium-based metal-organic framework (MOF) and graphene which can be 3D printed onto a ceramic to form the sensor. During their research, which is published in ACS Sensors, the sensor initially struggled to differentiate methanol and ethanol. However, after optimizing the sensor using trained machine learning algorithm, the sensor could differentiate methanol at the ppb level and ethanol at the ppm level.
While the sensor is a step towards a field ready device, the researchers say that additional development will be needed to distinguish methanol and ethanol in the high humidity of exhaled breath.