title: Chiral separation of glycyrrhetinic acid by high-performance liquid chromatography.
abstract: An HPLC separation of the 18 alpha and 18 beta diastereomers of glycyrrhetinic acid (GA) has been developed. The separation was achieved with a chiral column (Merck ChiraSpher, Darmstadt, Germany) and a methanol-water (65:35, v/v) mobile phase. The separation is excellent, having a resolution factor of 2.3. The HPLC method is efficient and accurate for the optical purity determination of 18 alpha- and 18 beta-GA samples. The run time is less than 30 min. Quantitation is linear with a lower detection limit of 0.2% for one isomer in the presence of the other. Addition of 0.2% acetic acid to the water in the mobile phase improved the ruggedness of the system without affecting the resolution of 18 alpha- and 18 beta-GA. This modification also allowed partial separation of 18 alpha- and 18 beta-glycyrrhizin, precursors of the GA isomers.
authors.affiliation: Life Sciences Division, SRI International, Menlo Park, CA 94025.
authors.forename: Y M
authors.initials: YM
authors.lastname: Ha
authors.forename: A P
authors.initials: AP
authors.lastname: Cheung
authors.forename: P
authors.initials: P
authors.lastname: Lim
mesh_terms: D002851:Chromatography, High Pressure Liquid; D006034:Glycyrrhetinic Acid / Q000302:isolation & purification*; D008956:Models, Chemical; D013237:Stereoisomerism
chemical_list: D006034:Glycyrrhetinic Acid