Creative Inquiry team creates electronic tongue
Detecting harmful chemicals within the bloodstream, determining the amount of pesticide run-off present in streams and lakes, and the quality control of biochemical process. These are just a few of the potential uses of the Electronic Tongue, a device being created by a Clemson Creative Inquiry group. Anthony Guiseppi-Elie, professor of electrical and computer engineering within the College of Engineering and Science, is leading the Creative Inquiry team that is researching and developing the device. The Electronic Tongue is a unique, bioelectronic device that can emulate the process of “taste” performed by the human tongue. Guiseppi-Elie’s team of student-scientists — identified as “the Vipers” due to the Electronic Tongue’s resemblance to that of a Viper’s tongue — is made up of chemical, bimolecular engineering and bioengineering majors. They are responsible for not only the engineering, testing and recording data of the Electronic Tongue, but also for figuring out the uses for such a device.
A member of the Viper’s team, Andrew Sedler, discussed how the process works. “When we apply a voltage across our device, molecules in the solution will react differently, depending on what their chemical makeup,” he said.
In the same way a human tongue detects food with receptors in its taste buds, the Electronic Tongue uses the data it collects from a pair of interlocking comb electrodes that are capable of sensing the electrical properties of the testing solution to which the electrodes are exposed. Multiple such comb electrodes, each decorated with different responsive polymer films called electroconductive hydrogels, comprise an array. Arrays can be arranged into receptors for the five basic taste categories of sweet, sour, bitter and salty and umami. It then uses the data collected during test conditions and gathers information about the “taste,” or the chemical makeup of whatever solution was tested for processing by classification software.
“Basically, this current response will tell us the amount of a specific molecule that is present. This can be applied to anything like taste testing in the food industry and pharmaceutical industry, among other areas,” Sedler said.
Using a program that was made specifically for that device by Pinnacle Technology called Serina (Bluetooth Dual Potentiostat), a current is generated through the device in contact with the test solution, which allows the group to calibrate the device and figure out what voltage is best suited to be applied. This current response will tell the scientists the amount of a specific molecule that is present, or what the solution “tastes” like. An exercise the team did was to consistently and repeatedly distinguish Coke® from Pepsi®. If given the same test, could you? In their test group, only 50 percent of people could.
“There are actually some products that do exist already, but they use transistors instead of an electrode voltage method like this,” Sedler said. In the future, the team will work on testing products for more specific molecules. Find out more about the Electronic Tongue Creative Inquiry here.