Selective high-performance liquid chromatographic method for the determination of glycyrrhizin and glycyrrhetic acid-3-O-glucuronide in biological fluids: application of ion-pair extraction and fluorescence labelling agent.
A selective high-performance liquid chromatographic method has been developed for the simultaneous determination of glycyrrhizin and glycyrrhetic acid-3-O-glucuronide in biological fluids of the rat. The procedure is based on the ion-pair formation using tetra-n-amylammonium bromide, extraction with ethyl acetate-n-heptane from the salt-saturated aqueous phase, labelling with 4-bromomethyl-7-methoxycoumarin, followed by chromatographic separation with fluorescence detection. Glycyrrhizin in plasma, bile and urine could be precisely determined in concentrations as low as 1, 1 and 2.5 micrograms/ml, respectively, in a 0.1-ml sample. The equivalent values for the glucuronide were 1, 2.5 and 2.5 micrograms/ml, respectively. The method is applicable in pharmacokinetic studies of glycyrrhizin in small animals.
Yamamura
Y
Y
Department of Pharmacy, University of Tokyo Hospital, Faculty of Medicine, Japan.
Kawakami
J
J
Santa
T
T
Kotaki
H
H
Uchino
K
K
Sawada
Y
Y
Iga
T
T
D000818:Animals; D001646:Bile / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D003374:Coumarins / Q000737:chemistry; D005456:Fluorescent Dyes; D006034:Glycyrrhetinic Acid / Q000031:analogs & derivatives* / Q000097:blood / Q000493:pharmacokinetics / Q000494:pharmacology / Q000652:urine; D019695:Glycyrrhizic Acid; D007477:Ions; D051381:Rats; D013050:Spectrometry, Fluorescence; D016339:Spectrometry, Mass, Fast Atom Bombardment
D003374:Coumarins; D005456:Fluorescent Dyes; D007477:Ions; C052400:glycyrrhetyl 3-monoglucuronide; D019695:Glycyrrhizic Acid; D006034:Glycyrrhetinic Acid