A new chemical sensor can signal when bacteria develops

Have you ever had a dental patient ask you if you are placing secret transmitters in his or her fillings or implants that could help the CIA or other agencies pick up messages from his or her teeth? If so, you probably chalked it up to a serious case of paranoia.

But a Princeton University team headed up by Michael McAlpine has developed a sensor that detects bacteria and can operate on the surface of teeth. The graphene-based device identifies bacteria at the level of single cells and reports this using wireless technology.