Sensor on a Chip for Real-Time Environmental Monitoring

University of Delaware researchers Juejun Hu and Chaoying Ni are creating tiny, sensitive devices that will detect organic, inorganic, and biological molecular species at low levels in the environment. They use a focused ion beam to punch holes into a thin strip of chalcogenide glass that is only a few micrometers thick. When light passes through the strip, molecules in the environment selectively absorb one or a few particular colors of the light. The unique optical absorption signals can then be used to identify the presence and concentration of the molecules of interest. Hu and Ni plan to group several of the chip-sized devices together to create a sensor capable of detecting multiple types of molecules. The devices could replace more traditional molecular detectors, which require bulky and expensive equipment.