Electronic Tongue Allows for Rapid Detection of Contaminants
09/01/2023
By Brooke Coupal
Safe drinking water is essential for survival, but getting it deployed to soldiers comes with significant logistical challenges.
“The U.S. Army relies a lot on bottled and bulk water, but you can only take a truck so far, and with the current supply chain, pallets of bottled water are expensive,” says Eric Brack, research chemist and project officer for individual and squad hydration at the U.S. Army DEVCOM Soldier Center in Natick, Massachusetts.
An alternative hydration option for soldiers out in the field is indigenous water sources like streams and lakes, but those come with the risk of contamination. Currently, military personnel can check for tainted water by sending samples back to the United States and then waiting four to six weeks to get results.
“What happens in the meantime?” Brack asks. “Soldiers are either drinking bottled water, or they’re drinking from the water source, which could be contaminated with heavy metals or bacteria.”
The Army needs a quicker testing method, and Prof. Pradeep Kurup, chair of the Department of Civil and Environmental Engineering, is working on a solution.
For the past four years, the DEVCOM Soldier Center has funded Kurup’s research on portable technology that can test for water toxins on-site.
“We are developing a handheld, user-friendly device that can be used by soldiers to rapidly evaluate the quality of water from indigenous sources,” Kurup says.
The device, called the Electronic Tongue, or E-Tongue for short, uses patented electrochemical sensors to detect heavy metals and pesticides through a disposable electrode immersed in a sample of water.
The E-Tongue, which was initially developed under a National Science Foundation grant, provides readings of concentration levels of contaminants and a color code that lets the user know if the water is safe. Over time, the device has evolved to allow for programming test parameters and saving test results.
“We are continuously upgrading the software and expanding its sensing capabilities,” Kurup says.
The E-Tongue can detect up to 11 different heavy metals that can be fatal to humans, such as arsenic, mercury and lead, as well as four pesticides, including methyl parathion, paraquat, fenamiphos and methomyl.
“This novel device could save lives,” Kurup notes.
Water Purification Meets Electronic Tongue
The development of the E-Tongue comes as the Army is looking at new technologies for purifying water.
“We need something to ensure that our current water purification devices are working properly,” Brack says. “That’s why we’re interested in a real-time water sensor.”
By using the E-Tongue before purifying the water, military personnel can determine which contaminants are present. From there, they can implement the correct purification technology to clean the water. The E-Tongue can then be used again to check how well the purification process worked.
“The lifespan of a filter all depends upon if contaminants are clogging up the filter medium,” Kurup says.
Brack predicts deployed troops will be outfitted with E-Tongues in the next two to three years.
“Our goal is to have soldiers eventually be able to test and purify any indigenous water source, from fresh water to salt water,” he says.
Ramaswamy Nagarajan, a plastics engineering professor and co-director of Harnessing Emerging Research Opportunities to Empower Soldiers (HEROES), has contributed his expertise to the development of the E-Tongue. More than a dozen graduate and undergraduate students and postdoctoral researchers have also assisted with the project.
“Working under the guidance of Prof. Kurup, I have gained hands-on experience in research methods and techniques, developed critical thinking and problem-solving skills, built relationships with mentors and colleagues and gained insights into voltammetric heavy metals detection in drinking water,” says Yigit Bozkurt ’20, a Ph.D. civil and environmental engineering student from Turkey.
Triple River Hawk Connor Sullivan ’14, ’16, ’21 has conducted research in Kurup’s lab since the summer of 2011. The North Andover, Massachusetts, native currently serves as a postdoctoral researcher, together with fellow postdoc Al-Monsur Jiaul Haque of Bangladesh.
“My main contribution to the E-Tongue has been developing the sensors and analytical methods for detecting contaminants,” Sullivan says. “Working on this project early in my studies at UMass Lowell helped spark my interest in research.”