Any chiral compound which can complex with your analyte(s) can be added to the mobile phase. The resulting complex will be diastereomeric; the diastereomers can (hopefully) be resolved. Probably the most commonly used complexing agents have been cyclodextrin derivatives. Although this approach has been used with HPLC, it is not very popular, because it consumes large quantities of expensive reagents.
It has proven more popular in capillary electrophoresis. The following quote is taken from:
http://www.chemsoc.org/chembytes/ezine/ ... _nov00.htm
Chiral separations
Cyclodextrin chemically substituted with sulphate groups
One area where CE has distinct advantages over other separation techniques is chiral analysis. Chiral separations are among the most widely used applications of CE. A chiral substance, usually a cyclodextrin, is added to the buffer. If the enantiomers of the analyte interact differently with the cyclodextrin then a chiral separation is feasible. The hydroxyl groups on the cyclodextrin can be chemically substituted with groups such as methyl, hydroxypropyl or sulphate. The structure below shows the structure of a cyclodextrin that has been chemically substituted with sulphate groups. These sulphated cyclodextrins have different interactions with the analytes and will therefore offer different separation possibilities. The analyst can optimise methods to test the purity of single enantiomer compounds, where a detection limit of 0.1 per cent is often required to determine of the trace level enantiomer impurity.
