Researchers at Oregon State University, United States, have developed a new microfluidic sensor that could revolutionize the size, speed and accuracy of chemical detection systems around the world. The scientists used magnetic “nanobeads” to develop a sensor to help detect chemical and biological agents, with potential applications in everything from bioterrorism to medical diagnostics, environmental monitoring, or even food and water safety. The key is the use of ferromagnetic iron oxide nanoparticles, which not only detect chemicals with sensitivity and selectivity, but can also be incorporated into a system that instantly displays the findings. Vincent Remcho, a professor of chemistry, said, “The particles we’re using are 1,000 times smaller than those now being used in common diagnostic tests, allowing a device to be portable and used in the field. Just as important, however, is that these nanoparticles are made of iron. Because of that, we can use magnetism and electronics to make them also function as a signaling device, to give us immediate access to the information available.” Eventually, when fully developed into a hand-held portable sensor, the device will provide a whole diagnostic laboratory on a single chip.