An improved method for the determination of betaine in Echinacea products
Ganzera, M.; Pujol, P.; Walker, L.; Khan, I.A.
Die Pharmazie 56(7): 552-553
2001
ISSN/ISBN: 0031-7144 PMID: 11487974 Document Number: 538133
A rapid and sensitive HPLC method for the separation and quantification of betaine in ten Echinacea (Echinacea angustifolia and E. purpurea) products (capsules, tablets, and liquids) has been developed. A strong cation-exchange material was used as stationary phase, and a mixture of methanol and 50 mM choline buffer (pH 3.5) as mobile phase. After formation of the bromophenacyl derivative, betaine was detected at 254 nm with a detection limit of 0.2 micro g/ml. The method was successfully used to analyse several Echinacea market products, and significant variations in their betaine content from 0.04 to 0.64% were observed.