Scientists fabricate sensitive nanostructured silver surfaces to detect arsenic, even at very low concentrations. The sensors make use of surface-enhanced Raman spectroscopy: As a molecule containing arsenic adheres to the surface, it’s hit with a laser and the arsenic compound scatters the laser light, creating an identifiable signature. The technique is a departure from existing methods, which are time-consuming, expensive, and not ideally suited to on-site field assays.
