Analysis of Kakkonto using Comprehensive Two-Dimensional LC Nexera-e

User Benefits

- Nexera-e system can be used for comprehensive two-dimensional separation. - Accurate quantitation of individual components can be obtained (glycyrrhizic acid).

Introduction

Kakkonto (traditional Chinese medicine) is believed to be effective against cold, headache, stiff shoulders, etc., because it has the properties to promote sweating and provide anti- inflammatory and analgesic action. It consists of various natural products such as puerariae radix, ephedra, licorice, paeoniae radix, etc. It contains many compounds such as ephedrine, glycyrrhizic acid, and cinnamic acid. The Nexera-e comprehensive two-dimensional LC system is useful to separate such a complex sample. In a comprehensive 2D-LC system configuration generally two pumps and two columns are used and the fractions from first dimension are continuously transferred to a second column (second dimension). This transfer is performed by filling two identical loops alternately through a synchronized valve switching. Generally, different separation modes are selected for first dimension (1D) and second dimension (2D) in comprehensive two-dimensional chromatography. This combination can usually provide higher resolution compared to the one- dimensional separation. Traditional Chinese medicine such as Kakkonto contains many relatively-polar compounds, so pH is also an important parameter to be considered. This article introduces a comprehensive two-dimensional separation using a semi-micro reversed-phase column and neutral pH mobile phase for 1D and an ultra-high speed reversed-phase column and acidic pH mobile phase for 2D. The standard solution of glycyrrhizic acid was analyzed and calibration curve was created. Furthermore, three commercial Kakkonto extract granule from different manufacturers were analyzed and the concentration of glycyrrhizic acid was determined.

August 24, 2022 GMT