Determination of glycyrrhizic acid and 18-β-glycyrrhetinic acid in biological fluids by micellar electrokinetic chromatography

Simultaneous determination of glycyrrhizin, a marker component in radix Glycyrrhizae, and its major metabolite glycyrrhetic acid in human plasma by LC–MS/MS

“…Detection of GLY and GA in biological fluids by high-performance liquid chromatography (HPLC) with ultraviolet detection [20][21][22][23][24][25] has been reported, but it was time consuming and lacked sensitivity. In addition, detection using capillary electrophoresia [25,26] and micellar electrokinetic chromatography [27] has been demonstrated in other studies. Although quantitative liquid chromatography/tandem mass spectrometry (LC-MS/MS) has become a common analytical tool for various compounds, however, an LC-MS/MS method suitable for the routine analysis of GLY and GA has not been reported.…”

Chemical analysis of raw, dry‐roasted, and honey‐roasted licorice by capillary electrophoresis

“…A capillary electrophoretic method has been developed to perform the chemical analysis, especially the chiral separation of 18-a and 18-b GA. To date, CE method has been employed to determine mostly single chemical constituent (i.e., GL) of licorice roots [12,13]. Although there are reports on multiple-component analysis of licorice using CE [14][15][16] and HPLC [16][17][18], none of these methods simultaneously determine GL, IQ, and 18-a and 18-b GA. We have selected to analyze these licorice components using CE because of its strong method development capability (e.g., changing run buffer additives and conditions), low consumption of materials (e.g., reagents and samples), and possibility of integration with miniaturized systems (e.g., lab-on-a-chip).…”

Simultaneous determination of 18α‐ and 18β‐glycyrrhetic acid in human plasma by LC‐ESI‐MS and its application to pharmacokinetics

“…In the literature, many extraction procedures for GA in biological samples have been employed, including protein precipitation (Tsai et al, 1991;Zhang et al, 1989;Tsai et al, 1992;Krahenbuhl et al, 1994b), liquid-liquid extraction (LLE) (Abe et al, 1994;Ding et al, 2006;Tian et al, 2007) and solid-phase extraction (Takeda et al, 1990;Gunnarsdottir and Johannesson, 1997;Wang et al, 1998;Lin et al, 2005). Based upon the previous work, our approach to developing an assay for the analytes was LLE with ethyl acetate, trichlormethane and ether alone or in combination in different concentrations.…”

“…The commonly used HPLC with UV detection methods for the determination of GA in human plasma and experimental animals have been published many times (Zhang et al, 1989;Takeda et al, 1990;Ha et al, 1991;Yamamura et al, 1991;Tsai et al, 1992;Abe et al, 1994;Krahenbuhl et al, 1994b;Takeda et al, 1996;Gunnarsdottir and Johannesson, 1997;Gao et al, 2004), but they were not sensitive enough for pharmacokinetic research of GA since the terminal phase concentrations of GA for most volunteers were below their low limit of quantitation (LOQ). The micellar electrokinetic chromatography has also been reported (Wang et al, 1998); it was a tentative experiment and was not practical for large batches of biological samples. Ding et al (2006) published a LC-MS assay to evaluate the pharmacokinetic profiles of GA. Lin et al (2005) reported an LC-MS/MS method for simultaneous determination of GLY and GA in human plasma, but it is only a validated method and has not been applied 55 to practical samples.…”