Researchers design scalable graphene sensor array for real-time toxins monitoring in flowing water
A team of researchers, led by the University of Wisconsin-Milwaukee, recently developed a path to mass-manufacture high-performance graphene sensors that can detect heavy metals and bacteria in flowing tap water. This advance could bring down the cost of such sensors to just US $1 each, allowing people to test their drinking water for toxins at home.
The sensors have to be extraordinarily sensitive to catch the minute concentrations of toxins that can cause harm. For example, the U.S. Food and Drug Administration states that bottled water must have a lead concentration of no more than 5 parts per billion. Today, detecting parts-per-billion or even parts-per-trillion concentrations of heavy metals, bacteria, and other toxins is only possible by analyzing water samples in the laboratory, says Junhong Chen, a professor of molecular engineering at the University of Chicago and the lead water strategist at Argonne National Laboratory. But his group has developed a sensor with a graphene field-effect transistor (FET) that can detect toxins at those low levels within seconds.