Measuring the amount of enantiomeric excess

Chirality is a property of molecules with one or more stereocenters. Polarimeters are able to distinguish between dextrorotatory and levorotatory molecules. In chemistry, a molecule is called chiral if it cannot be superposed on its mirror image by any combination of rotations or translations, like as one’s left and right hands. That is the case if the molecule has at least one stereocenter. The molecule and its mirror image are called enantiomers. Enantiomeric purity is very important for pharmaceutical applications, since the different enantiomers have different physiological effects. The amount of enantiomeric excess (EE) or the racemic mixtures can be measured with polarimetry.