Determination of glycyrrhizic acid and 18-beta-glycyrrhetinic acid in biological fluids by micellar electrokinetic chromatography.
A micellar electrokinetic chromatographic technique for determining acid (GZA) and 18 beta-glycyrrhetinic acid (GRA) in human plasma and urine was developed. Sample clean-up and analyte concentration were carried out by solid-phase extraction (with C18 sorbent). The buffer solution used for MEKC contained 20 mM sodium dihydrogenphosphate, 20 mM sodium tetraborate, 20 mM tetrabutylammonium bromide and 50 mM sodium dodecylsulphate, at a pH of 8.7. Good linearities for both GZA and GRA in plasma and urine were obtained. The recoveries of the method were in the range 86.5 to 107%. The detection limits for GZA in urine (0.5 ml) and plasma (1 ml) were 1.6 micrograms ml-1 and 0.8 micrograms ml-1, respectively, while for GRA in urine (0.5 ml) and plasma (1 ml) were 2 micrograms ml-1 and 1 micrograms ml-1, respectively.
Wang
P
P
Department of Chemistry, National University of Singapore, Singapore.
Li
S F
SF
Lee
K H
KH
D002021:Buffers; D002138:Calibration; D002845:Chromatography; D004563:Electrochemistry; D006034:Glycyrrhetinic Acid / Q000032:analysis* / Q000097:blood / Q000652:urine; D019695:Glycyrrhizic Acid / Q000032:analysis* / Q000097:blood / Q000652:urine; D006801:Humans; D007202:Indicators and Reagents; D008823:Micelles; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet
D002021:Buffers; D007202:Indicators and Reagents; D008823:Micelles; D019695:Glycyrrhizic Acid; D006034:Glycyrrhetinic Acid