14 DAY TRIAL // An international collaboration of researchers featuring scientists from the Swiss Federal Institute of Technology (EPFL), Northwestern University and the University of Michigan announces the development of a new sensor that is extremely effective at detecting mercury in fluids.
The instrument is very simple to produce, since it consists of a single strip of glass, covered in what could be referred to as “hairy” nanoparticles. In laboratory experiments, this setup proved very efficient at detecting even trace amounts of mercury and other toxic metals in various liquids.
Having access to such a capability is very important, researchers say, because these chemicals can attack and damage the human nervous system. Its concentrations are increasing steadily, as more pollution makes its way into the air and water.
Coal power plants, for example, release significant amounts of mercury into the air, which can eventually make its way into water sources, and then contaminates the general population.
In a series of experiments, the joint team demonstrated that their new device is capable of detecting unprecedentedly-small amounts of methyl mercury, the most common form of the toxic chemical.
Details of how the system operates, and the exact amounts of mercury it can detect, were published in the latest issue of the top scientific journal Nature Materials.
An added benefit of the new detector is that it can also gage the amount of methyl mercury in fish, which are natural sponges for the compound. Large, predatory fish, including tuna and swordfish, exhibit the highest concentrations of mercury.
The stuff affects the development of the human brain and nervous system, which is why pregnant women and small children are discouraged from eating fish during critical months.
“The problem is that current monitoring techniques are too expensive and complex. With a conventional method, you have to send samples to the laboratory, and the analysis equipment costs several million dollars,” says the EPFL Constellium Chair holder, researcher Francesco Stellacci.
The new system is extremely easy to use. Researchers simply dip the strip of glass holding the nano-velcro material inside a fluid, and then pass an electrical current through it. This reveals the concentration of toxic metals in the test liquid.
“By making detection of pollutants and toxins cheap and easy to do, more testing at the source will lead to safer foods on the dinner table and in kids' lunchboxes,” the U-M Churchill Professor of Chemical Engineering, Sharon Glotzer, concludes.