Enantiomeric separation and determination of antiparkinsonian drugs by reversed-phase ligand-exchange high-performance liquid chromatography.

A simple and rapid high-performance liquid chromatographic method for the separation and determination of enantiomers of levodopa and carbidopa using a LiChrosper C18 column with aqueous copper-L-phenylalanine as mobile phase was developed. The separation between D- and L-enantiomers of levodopa and carbidopa was fairly good with separation factors of 1.63 and 2.38, respectively. The method was validated using synthetic mixtures and used for quality assurance of commercial formulations.