Tufts University engineers have developed a novel fabrication method to create dyed threads that change color when they detect a variety of gases. The researchers demonstrated that the threads can be read visually, or even more precisely by use of a smartphone camera, to detect changes of color due to analytes as low as 50 parts per million. Woven into clothing, smart, gas-detecting threads could provide a reusable, washable, and affordable safety asset in medical, workplace, military and rescue environments, they say. The study, published today in the journal Scientific Reports, describes the fabrication method and its ability to extend to a wide range of dyes and detection of complex gas mixtures.