Chirality is an inherent property of carbon-based compounds, and the ability to discriminate between the enantiomers of a biological molecule is important for applications in archeology, pharmaceutics and the food industry. Until now, techniques to detect enantiomeric impurities have relied on chemical properties of the molecules and have suffered from a low sensitivity. In this issue, Green and colleagues provide a novel antibody-based immunosensor with a 10 fold greater sensitivity to enatiomeric impurities than current sensor methodologies (see p. 371).