Knotted molecules can transfer chirality from the nano to the macroscale

Knots are common in long molecules such as proteins and DNA, but both the method by which they form and the mechanism by which they effect a molecule’s macroscopic function remains unclear. Now, however, researchers from the Netherlands and the UK have shown that the chirality of liquid crystals can be inverted by unknotting a molecule that has been added to it. This provides a far less energetically-expensive means of inverting chirality than methods developed previously, and demonstrates that nanoscale knotting can have macroscopic effects.