Telling left from right: chirality detection faces up to its weaknesses

Like Oscar Wilde’s Dorian Gray there are many molecules with a sinister mirror image twin. Failure to recognise the distinct properties of a molecule’s mirror image version can have tragic consequences, as demonstrated by the thalidomide scandal in the 1950s and 1960s. Chiral molecules interact with other chiral structures differently from their mirror image twin and being widespread in nature, they have been exploited in pharmaceuticals, agriculture, cosmetics and food. The net global market is currently valued at over $70 billion (£57 billion) creating high stakes for correctly telling apart the two mirror-image molecules or enantiomers.

But as enantiomers are chemically identical, distinguishing between the two using physical properties like boiling and melting points or density is impossible. If you visit a lab in academia or industry it is likely that chemists will be using techniques that are at least 50 years old to distinguish between enantiomers, despite their shortcomings. But now some of the world’s best informed and most creative chiral specialists are developing an array of technologies to overcome these problems when it comes to telling one enantiomer from the other.