In applications that use a single quantum dot, such as biological sensors, this fallibility can have dramatic consequences. Quantum dots are generally brighter and longer-lived than organic dyes used today, and are increasingly used in biology to tag biomolecules. Once tagged, the dot’s emissions will act as a beacon for scientists, allowing them to track the target biomolecule. But if a dot blinks, scientists may lose track of their biomolecule. It’s like trying to radio-track wolves with capricious transmitters that could cease transmitting at any moment.