Research scientists at the University of Michigan, Ann Arbor, Mich., announced plans to develop a paper-based, cell-free system that detects spoiled milk, according to this study hypothesis.
Relying on the detection of AHL molecules used by bacteria in quorum sensing, this system will be a synthetic gene network freeze-dried on paper. When AHL is present, the system is projected to produce a red pigment providing a visual cue the milk is spoiled. Because spoiled milk contains bacteria-producing AHL, when the system comes into contact with spoiled milk, the paper should turn red.
