An electrochemical sensor developed at Oregon State University holds promise for making food quality testing faster, more accurate, more environmentally friendly and less expensive.
The novel sensor, which also has potential applications in health care and environmental monitoring, is based on the design principle of engineered interfacial chemistry.
The sensor requires tiny sample amounts, can be built into portable testing devices, and is fast and highly sensitive.
Funded by the National Science Foundation, the study by scientists at Oregon State and researchers in Taiwan was published in Applied Nano Materials, a journal of the American Chemical Society.
The collaboration led by Mas Subramanian and Gopika Meenakumari Gopakumar of the OSU College of Science engineered a nanocomposite sensing material consisting of strontium oxide, functionalized carbon black (tiny particles of almost pure carbon), and reduced graphene oxide.
Together, these components formed a highly conductive interface that enhanced adsorption, accelerated electron transfer and improved the electrochemical oxidation of theobromine, the compound the scientists sought to detect in barley tea, black tea, green tea, coffee and chocolate milk.
Chemically similar to caffeine and found in cocoa-derived products, theobromine is a mood elevator in humans, producing a sense of calm alertness, and is what makes chocolate toxic to dogs.
“Accurate measurement of theobromine is important for food quality control, labeling consistency and consumer safety,” said Subramanian, university distinguished professor and Milton-Harris Professor of Materials Science in the Department of Chemistry. “The compound contributes to flavor and mild stimulant effects, and its reliable monitoring is especially valuable in formulations requiring precise composition. Theobromine detection may also have broader applications in toxicological and analytical studies.”
