Silica-based phase for HPLC enantiomer separation. Principle interaction modes - charge-transfer interactions, hydrogen bonds, dipole-dipole interactions and steric effects. For control of the optical purity of a substance, the two columns NUCLEOSIL CHIRAL-2 and NUCLEOSIL CHIRAL-3 allow to select conditions such that the minor enantiomer, which is present as an impurity, is eluted before the main peak. Thus, overlapping peaks are avoided. This makes an exact quantification of the impurity much easier. Based on the original NUCLEOSIL silica gel. It is one of the first spherical silicas for HPLC and was originally developed by MACHEREY-NAGEL in 1974. It is exclusively manufactured in Germany and is still one of the most used HPLC silicas in quality control around the globe.